US20070050039A1 - Orthopaedic implant, stem and associated method - Google Patents

Abstract

An orthopaedic implant for use in performing joint arthroplasty is provided. The orthopaedic implant includes a joint component having a stem element defining a external periphery of the stem element. The external periphery of the stem element has a stem resection ring that may be aligned with the resected plane of the long bone. The joint component also includes a body element, which is capable of being fixedly fitted to the stem element and having an external periphery with a body resection ring alignable with the resected plane of the long bone. The external periphery of a canal portion of the body element is spaced inwardly from the external periphery of the stem element so that the body element may be removed from the long bone without disturbing the fixation of the stem element to the long bone.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• Cross reference is made to the following applications: DEP5557USNP titled “ORTHOPAEDIC IMPLANT STEM COMPONENT, JOINT COMPONENT, AND ASSOCIATED KIT” and DEP5563USNP titled “ORTHOPAEDIC IMPLANT KIT, ORTHOPAEDIC SURGERY KIT AND ASSOCIATED METHOD” filed concurrently herewith which are incorporated herein by reference.
TECHNICAL FIELD OF THE INVENTION
• The present invention relates generally to the field of orthopaedics, and more particularly, to an implant for use in arthroplasty.
BACKGROUND OF THE INVENTION
• Patients who suffer from the pain and immobility caused by osteoarthritis and rheumatoid arthritis have an option of joint replacement surgery. Joint replacement surgery is quite common and enables many individuals to function properly when it would not be otherwise possible to do so. Artificial joints are usually comprised of metal, ceramic and/or plastic components that are fixed to existing bone.
• Such joint replacement surgery is otherwise known as joint arthroplasty. Joint arthroplasty is a well-known surgical procedure by which a diseased and/or damaged joint is replaced with a prosthetic joint. In a typical total joint arthroplasty, the ends or distal portions of the bones adjacent to the joint are resected or a portion of the distal part of the bone is removed and the artificial joint is secured thereto.
• There are known to exist many designs and methods for manufacturing implantable articles, such as bone prostheses. Such bone prostheses include components of artificial joints such as elbows, hips, knees and shoulders.
• Currently in total hip arthroplasty, a major critical concern is the instability of the joint. Instability is associated with dislocation. Dislocation is particularly a problem in total hip arthroplasty.
• Factors related to dislocation include surgical technique, implant design, implant positioning and patient related factors. In total hip arthroplasty, implant systems address this concern by offering a series of products with a range of lateral offsets, neck offsets, head offsets and leg lengths. The combination of these four factors affects the laxity of the soft tissue. By optimizing the biomechanics, the surgeon can provide a patient a stable hip much more resistant to dislocation. In order to accommodate the range of patient arthropometrics, a wide range of hip implant geometries are currently manufactured by DePuy Orthopaedics, Inc., the assignee of the current application, and by other companies. In particular, the S-ROM® total hip systems offered by DePuy Orthopaedics, Inc. include three offsets, three neck lengths, four head lengths and one leg length adjustment. The combination of all these biomechanic options is rather complex.
• Anteversion of a total hip system is closely linked to the stability of the joint. Improper version can lead to dislocation and patient dissatisfaction. Version control is important in all hip stems. However, it is a more challenging issue with the advent of stems with additional modularity.
• The prior art has provided for some addressing of the anteversion problem. For example, the current S-ROM® stems have laser markings on the medial stem and the proximal sleeve. This marking enables the surgeon to measure relative alignment between these components. Since the sleeve has infinite anteversion, it is not necessarily oriented relative to a bony landmark that can be used to define anteversion. In fact, the current sleeves are sometimes oriented with the spout pointing directly laterally into the remaining available bone.
• Prior art stems may be aligned relative to a patient's bony landmarks. These stems are monolithic. They cannot locate the neck independently of the distal stem. Therefore, anteversion is limited. Most bowed, monolithic stems are sold in fixed anteversion; for example, at an anteversion of 15 degrees. These monolithic stems have limited flexibility for rotational alignment since the distal stem must follow the bow of the patient's femur and this may not provide an operable biomechanical result.
• In a common step in the surgical procedure known as total hip arthroplasty, a trial or substitute stem is first implanted into the patient. The trial is utilized to verify the selected size and shape of the implant in situ on the patient and the patient is subjected to what is known as a trial reduction. This trial reduction represents moving the joint, including the trial implant through selected typical motions for that joint. Current hip instruments provide a series of trials of different sizes to help the surgeon assess the fit and position of the implant. Trials, which are also known as provisionals, allow the surgeon to perform a trial reduction to assess the suitability of the implant and implant's stability prior to final implant selection.
• Most hip stems implanted currently are of a one-piece or mono-block design. Mono-block hip stem designs allow for no adjustments. Thus, they require that the hip stem be removed and replaced to adjust head height or offset. Also, mono-block stems are not designed to be used in minimally invasive surgery and are not optimal for use with minimally invasive surgery procedures.
• Surgical variables such as leg length discrepancy may result in surgical error that may need to be corrected or optimized. Further, due to implant subsidence during the use of an implant, the head-height at a revision surgery may need to be corrected. Further, revision surgery may be required to correct the instability of the hip joint. Stability may be restored by moving the head proximally and or increasing the offset of the implant to tighten the soft tissues. These corrections may be made at revision surgery to address these dislocations, however with current mono-block stems the stem must be removed from the femur to accomplish these changes in the implant configuration. Such removal of the stem from the femur may make the revision surgery quite difficult in that the stem tends to engrow with the tissues of the bone. Also, removal of the stem may lead to significant loss of bone, which can compromise the fixation of the stem upon re-implantation.
• Further revision surgery may be required to correct weak abductor function by increasing the offset of the stem. The changing in a revision surgery to an increased offset stem may require that the stem be removed from the medullary canal of the femur and replaced with a stem with a different offset.
• Further mono-block stems are not easily used in minimally invasive hip procedures where the incision through the skin and soft tissue is minimized. The surgeon may have difficulty to work in the joint space after the stem is in place. The neck of the mono-block stem may be in the way during the performance of the surgery.
• In order to reduce inventory costs and complexity, many trialing systems are modular. For example, in the Excel Instrument System, a product of DePuy Orthopaedics, Inc., there is a series of broaches and neck trials that can be mixed and matched to represent the full range of implants. There is a single fixed relationship between a broach and a neck trial, because these trials represent a system of monolithic stem implants.
• Likewise, in the current S-ROM® instrument systems provided by DePuy Orthopaedics, Inc., there are neck, proximal body, distal stem, head and sleeve trials. By combining all these components, the implant is represented. Since the S-ROM® stem is modular and includes a stem and a sleeve, the angular relationship or relative anteversion between the neck and the sleeve is independent and represented by teeth mating between the neck and the proximal body trial. The proximal body trial has fixed transverse bolts that are keyed to the sleeve in the trialing for straight, primary stems. The long stem trials do not have the transverse bolts and are thus not rotationally stable during trial reduction and therefore are not always used by the surgeon.
• Prosthetic joint implants are currently surging in use and technology. In performing most prosthetic joint implants, what is known as a ‘trial’ or ‘provisional’ is used before a final prosthesis is used. The trial or provisional is used to select the proper joint prosthesis and/or to orient or align one or more of the components of the final joint prosthesis. The trial or trial components are temporarily implanted to achieve proper sizing, placement and/or orientation of the final joint prosthesis, as well as achieve anatomical orientation of the prosthesis and/or components of the joint prosthesis.
• Hip arthroplasty provisionals or trials have a neck that is used to attach a femoral head provisional or trial thereto. The orientation of the neck relative to the shaft of the broach or trial is described in terms of anteversion, neck length, neck angle, and/or neck offset. Because each patient's original femoral neck anatomy is different, the ability to replicate the original femoral neck anatomy of each patient during hip arthroplasty requires multiple neck trials having various orientations. The use of multiple neck segments is not advantageous since it requires more time, increased instrument cost and increased space in the instrument sterilization case.
• Thus, trialing systems utilized by many hip implants or prostheses generally consist of a broach and a neck segment. In order to intraoperatively change the offset of the trial (i.e. neck segment and broach), the neck trial must be removed and another neck trial must be put in its place. Thus, multiple neck trials that are exchangeable with one another relative to the broach are necessary in order to replicate the original hip anatomy.
• Other hip systems utilize only one neck segment with the offset incorporated into the location of the trunnion of the broach. This design, however, does not mimic the exact geometry of the actual implant. While it is desired to be able to try several neck offsets relative to the broach in order to achieve a proper head positioning for the final implant, the prior art is deficient.
• In U.S. Pat. No. 5,645,607 issued to Hickey, a hip trial or prosthesis having an adjustable neck portion is disclosed in which the problem of multiple neck trials is addressed. The adjustable neck of Hickey allows the trialing of various neck offsets in order to achieve a correspondence between the spatial orientation of a patient's original anatomy and a final implanted hip ball prosthesis.
• However, Hickey requires a vertical height change of the neck segment in order to move between the various offsets. Where vertical height is restricted during surgery, especially in current, less invasive arthroplasty procedures, vertical height adjustment is undesirable.
• There are a variety of modular stem designs in the prior art. Most of these designs focus on the ability to use varying stem diameters and length with various size proximal bodies to provide optimal fill on both the diaphysis and the metaphysis simultaneously (to optimize fixation of the device). In many of these designs the neck cannot be removed or replaced to adjust head-height or offset without disturbing the fixation of at least the modular proximal body portion of the stem. Prior art modular stems include the modular stem as disclosed in U.S. Pat. No. 5,370,706 to Bolesky, et al. and assigned to the applicant of the instant application. The Bolesky patent, U.S. Pat. No. 5,370,706 is hereby incorporated in its entirety by reference.
• Another modular stem available in the prior art is the S-ROM® stem sold by DePuy Orthopaedics, Inc., Warsaw, Indiana and described in U.S. Pat. No.'s 4,624,673, 4,790,852, and 4,846,839. The U.S. Pat. No.'s 4,624,673, 4,790,852, and 4,846,839 are incorporated herein by reference in their entireties.
• The prior art further includes a modular stem marketed by Wright Medical, Inc. of Arlington, Tennessee. The Pro-Femur Stem provides a modular neck with a taper on both ends, one to engage the stem proximal body and one to engage the head.
• The present invention is adapted to solve at least some of the aforementioned problems with the prior art.
SUMMARY OF THE INVENTION
• An aspect of the present invention is in the form of a hip stem that utilizes a modular neck portion. The hip stem includes two main parts. These parts are a hip stem body and a modular neck portion. The modular neck provides the surgeon the ability to adjust the proximal-distal head height and the head offset. These adjustments may be either independent or in combination with each other. The adjustment can be made after the stem is seated and fixed into place, eliminating the need to disturb the fixation of the stem. The adjustment can take place as fine tuning at the end of the initial orthopaedic surgery or upon a revision surgery when it is determined that the cause for the revision (such as instability or leg length discrepancy) may be addressed by adjustment.
• The design of an aspect of the present invention allows the stem body to be implanted separately from the modular neck portion. This feature may be advantageous in minimally invasive surgery where smaller components may be easier to place through smaller incisions and where waiting until near the end of the operation to implant the neck portion provides more room for the surgeon to work and better access to the joint space.
• According to yet another aspect of the present invention, the hip stem design includes two main parts, a hip stem body and a modular neck portion. The modular neck portion fits within a recess in the top of the stem body. This modular design allows the modular neck portion to be placed or removed without disturbing the fixation of the stem body in the bone. A variety of methods can be used to obtain mechanical attachment of the modular stem portion to the body.
• For example, in one embodiment of the present invention, dowel pins are pressed into one side of the interface with a tight slip fit on the other side to align and aid in carrying bending moments across the interface. This design ensures that the screw (which is used to apply the compressive locking forces across the interface) is subjected only to axial tension loads. By eliminating bending moments in the screw, fatigue failure of the thread fastener can be better avoided.
• According to another aspect of the present invention, a means for holding the screw captive in the modular stem portion may be desirable to aid in assembling the modular stem portion to the stem body. Such capture of the screw would minimize the number of parts to be handled and eliminate the need to handle or assemble many small pieces.
• In yet another embodiment of the present invention, the dowel pins are replaced with tapers, which may be either rectangular or cylindrical. The tapers serve to align the parts and carry any bending moments so that the screw is subjected to only axial tension loads.
• In yet another aspect, the present invention provides a hip stem for use in performing hip arthroplasty. The hip stem is to be fitted to a cavity in the canal of a femur. The hip stem includes a stem component including a distal stem portion and a proximal body portion. The hip stem also includes a neck component fixedly connectable to the stem component. The neck component includes a proximal neck portion and a distal body portion. The neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone.
• In another aspect, the present invention provides a hip prosthesis for use in performing hip arthroplasty. The hip stem is fitted to a cavity in the canal of a femur. The hip prosthesis includes an acetabular cup, a head, a neck component and a stem component. The stem component includes a distal stem portion and a proximal body portion. The neck component is fixedly connectable to the stem component. The neck component includes a proximal neck portion and a distal body portion. The neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone.
• In another aspect, the present invention provides a kit for performing revision surgery. The kit includes a stem component having a distal stem portion and a proximal body portion. The kit also includes a first neck component fixedly connectable to the stem component. The first neck component includes a proximal neck portion and a distal body portion. The first neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone. The kit also includes a second neck component fixedly connectable to the stem component. The second neck component includes a proximal neck portion and a distal body portion. The second neck component is adapted for removal from the femur without disturbing the fixation of bone surrounding the stem component.
• In another aspect, the present invention provides an orthopaedic implant for use in performing joint arthroplasty. A portion of the orthopaedic implant is to be fitted to a cavity in the canal of a long bone. The orthopaedic implant includes a stem component having a stem portion and a body portion. The orthopaedic implant also includes a joint component fixedly connectable to the stem component. The joint component has an articulation portion and a connection portion. The joint component is adapted for removal from the long bone without disturbing the fixation of bone surrounding the stem.
• In another aspect, the present invention provides a stem component for use with a joint component having an articulation portion and a connection portion in performing joint arthroplasty. At least a portion of the stem component is to be fitted to a cavity in the canal of a long bone. The stem component includes a stem portion and a body portion. The body portion is adapted to permit removal of the connection portion of the joint component from the long bone without disturbing the fixation of bone surrounding the joint component.
• In another aspect, the present invention provides a joint component for use with a stem component having a body portion and a stem portion in performing joint arthroplasty. At least a portion of the stem component is to be fitted to a cavity in the canal of a long bone. The joint component includes a connection portion and an articulation portion. The connection portion is adapted to permit the removal of the joint component from the long bone without disturbing the fixation of bone surrounding the joint component.
• In another aspect, the present invention provides an orthopaedic implant trial for use in performing joint arthroplasty and to assist in performing a trial reduction in performing joint arthroplasty. A portion of the orthopaedic implant trial is fitted to a cavity in the canal of a long bone. The orthopaedic implant trial includes a stem component having a stem portion and a body portion. The orthopaedic implant trial also includes a joint component fixedly connectable to the stem component. The joint component has an articulation portion and a connection portion. A portion of the body portion of the stem component extends over a portion of the connection portion of the joint component.
• In another aspect, the present invention provides a kit for use in performing joint arthroplasty. The kit includes an orthopaedic implant trial for use in performing joint arthroplasty. The trial is to be fitted to a cavity in the canal of a long bone and to assist in performing a trial reduction in performing joint arthroplasty. The orthopaedic implant trial includes a stem component having a stem portion and a body portion. The orthopaedic implant trial also includes a joint component fixedly connectable to the stem component. The joint component has an articulation portion and a connection portion. The joint component is adapted for removal from the long bone without disturbing the fixation of the stem component to the bone. The kit includes an orthopaedic implant for use in performing joint arthroplasty. A portion of the orthopaedic implant is fitted to a cavity in the canal of a long bone. The orthopaedic implant includes a stem component having a stem portion and a body portion. The orthopaedic implant also includes a joint component fixedly connectable to the stem component. The joint component includes an articulation portion and a connection portion. The joint component is adapted for removal from the long bone without disturbing the fixation of bone surrounding the joint component.
• In another aspect, the present invention provides a method for treating orthopaedic joint disease of a patient. The method includes the step of implanting an orthopaedic implant into a cavity in the canal of a long bone. The orthopaedic implant includes a stem component and a first joint component fixedly connectable to the stem component. The joint component is adapted for removal from the long bone without disturbing the fixation of the stem component to the bone. The method also includes the steps of monitoring the condition of the patient and determining that the patient needs a revision prosthesis. The method also includes the steps of providing a second joint component compatible with the stem component and removing the first joint component from the stem component of the orthopaedic implant in vivo in the patient without disturbing the fixation of bone surrounding the orthopaedic implant. The method also includes the step of implanting the second joint component into the stem component in vivo in the patient.
• In another aspect, the present invention provides a method for providing revision joint arthroplasty on a patient having an orthopaedic implant. The orthopaedic implant includes a stem component and a first joint component fixedly connectable to the stem component. The joint component is adapted for removal from the long bone without disturbing the fixation of the stem component to the bone. The method includes the steps of monitoring the condition of the patient and determining that the patient needs a revision prosthesis. The method also includes the steps of providing a second joint component compatible with the stem component and removing the first joint component from the stem component of the orthopaedic implant in vivo in the patient without disturbing the fixation of bone surrounding the orthopaedic implant. The method also includes the step of implanting the second joint component into the stem component in vivo in the patient.
• In another aspect of the present invention an orthopaedic implant for use in performing joint arthroplasty is provided. A portion of the implant is fitted to a cavity in the canal of a long bone. The cavity extends from a resected plane of the long bone. The implant includes a joint component having a stem element with an external periphery. The stem element defines a distal end for insertion into the cavity. The external periphery of the stem element has a resection ring that aligns with the resected plane of the long bone and a body element fixedly connectable to the stem element. The body element has a external periphery. A distal portion of the body element extends from the resection ring toward the distal end of the stem element. The periphery of the body element is spaced from the external periphery of the stem element so that the body element may be removed without disturbing the fixation.
• According to yet another aspect of the present invention an orthopaedic implant stem for use in performing joint arthroplasty is provided. A portion of the orthopaedic implant stem is to be fitted to a cavity in the canal of a long bone. The orthopaedic implant stem includes a distal element defining an external periphery of the distal element. The distal element defines a distal end of the element for insertion into the cavity and an opposed connection end. The distal element defines a recess therein extending from the opposed connection end of the distal element. The orthopaedic implant stem component also includes a proximal element fixedly connectable to the distal element. A distal portion of the proximal element extends generally from the connection end of the distal element toward the distal end of the distal element when the proximal element is fixedly connected to the stem. The distal portion of the proximal element is spaced inwardly from the external periphery of the distal element when the proximal element is fixedly connected to the stem component so that the proximal element may be removed from the long bone without disturbing the fixation of the distal element to the long bone.
• According to another aspect of the present invention a method for treating orthopaedic joint disease of a patient is provided. The method includes the steps of resecting a long bone along a resection plane and preparing a cavity in the canal of the long bone. The method includes the step of implanting an orthopaedic implant into a cavity in the canal of a long bone. The orthopaedic implant includes a joint component having a stem element and a first body element fixedly connectable to the stem element. The orthopaedic implant is secured in the canal of the long bone with the body element being spaced from the long bone. The method further includes the steps of monitoring the condition of the patient, determining that the patient needs a revision prosthesis, providing a second body element compatible with the stem element, and removing the first body element from the stem element of the orthopaedic implant in vivo in the patient without disturbing the fixation of bone surrounding the stem element of the orthopaedic implant and without damaging bone surrounding the first body element. The method also includes the step of implanting the second body element into the stem element in vivo in the patient.
• According to yet another aspect of the present invention an orthopaedic implant for use in performing joint arthroplasty is provided. A portion of the orthopaedic implant is capable of being fitted to a cavity in the canal of a long bone. The cavity extends from a resected plane of the long bone. The orthopaedic implant includes a joint component. The joint component includes a stem element defining an external periphery of the stem element. The stem element has a first end for insertion into the cavity. The external periphery of the stem element has a stem resection ring. The stem resection ring may be aligned with the resected plane of the long bone. The joint component also includes a body element, which is capable of being fixedly fitted to the stem element. The body element includes an external periphery. The external periphery of the body element has a body resection ring. The body resection ring may be aligned with the resected plane of the long bone. A canal portion of the body element extends generally from the resection ring of the external periphery of the body element toward the first end of the stem element when the body element is fixedly connected to the stem element. The external periphery of the canal portion of the body element is spaced inwardly from the external periphery of the stem element when the body element is fixedly connected to the stem so that the body element may be removed from the long bone without disturbing the fixation of the stem element to the long bone.
• According to a further aspect of the present invention an orthopaedic implant stem for use in performing joint arthroplasty is provided. A portion of the orthopaedic implant stem may be fitted to a cavity in the canal of a long bone. The orthopaedic implant stem includes a canal element having an external periphery. The canal element has a first end for insertion into the cavity and an opposed connection end. The canal element has a recess extending from the opposed connection end of the canal element. The recess has a internal periphery. The canal element also has an external periphery spaced outwardly from the internal periphery of the recess. The orthopaedic implant stem further includes a body element that may be fixedly connected to the canal element. A first portion of the body element may be inserted into the recess of the canal element when the first element is fixedly connected to the canal element. The first portion of the body element is spaced inwardly from the external periphery of the canal element when the body element is fixedly connected to the canal element so that the body element may be removed from the long bone without disturbing the fixation of the canal element to the long bone.
• According to a another aspect of the present invention a method for treating orthopaedic joint disease of a patient is provided. The method includes the steps of resecting a long bone along a resection plane and preparing a cavity in the canal of the long bone. The method also includes the step of implanting an orthopaedic implant into a cavity in the canal of the long bone. The orthopaedic implant includes a joint component having a canal element and a first body element. The first body element may be fixedly connected to the canal element. The orthopaedic implant is secured in the canal of the long bone with the first body element being spaced from the long bone. The method further includes the steps of monitoring the condition of the patient and determining that the patient needs a revision prosthesis. The method also includes the steps of providing a second body element connectable to the canal element and removing the first body element from the canal element of the orthopaedic implant in vivo without disturbing the fixation of bone surrounding the canal element of the orthopaedic implant and without damaging bone surrounding the first body element. The method further includes the step of implanting the second body element into the canal element in vivo.
• The technical advantages of the present invention include the ability to independently adjust the head-height and the head offset without disturbing the fixation of the stem in the bone. For example, according to one aspect of the present invention a hip stem is provided including a stem component including a distal stem portion and a proximal body portion and a neck component. The neck component is fixably connected to the stem component. The neck component includes a proximal neck portion and a distal body portion. The neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone. Thus, the present invention provides for the ability to independently adjust the head-height and the head offset without disturbing the fixation in the stem of the stem in the bone by merely changing the neck component by removing the neck component from the stem component while the stem component is in position in the bone.
• The technical advantages of the present invention further include the ability to enhance minimally invasive hip procedures by having smaller incisions for the stem and neck. For example, according to another aspect of the present invention, a hip stem is provided including a stem component having a distal stem component and a proximal body portion and a neck component. The neck component is fixably connectable to the stem component. The neck component includes a proximal neck portion and a distal body portion. The neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone. The stem component may thus be first inserted into the incision, put in position and then the neck component may be secured to the stem component. Thus the present invention provides for the enhancing of minimally invasive hip procedures by having smaller incisions for the stem and body. By allowing the neck portion to be inserted separately from the stem body, the implants may be inserted through a smaller incision with reduced soft tissue stretching and allowing the surgeon more space to work within the joint space until later in the procedure when the neck portion is inserted. In other words, the stem may be positioned in the incision and through the soft tissue put in place in the canal of the long bone and, in fact, cemented into position and permitted to be fixably secured into the proper position. At that time, the neck portion may then be inserted through the incision and the procedure continued.
• The technical advantages of the present invention include the ability to permit common hip prostheses to be used for right and left hand versions of the hip prosthesis. For example, according to yet another aspect of the invention, a hip stem is provided with a stem component and a neck component. At least one of the stem component and the neck component are adapted to permit the stem component and neck component to have a first assembly relationship as well as a second assembly relationship which is different than the first assembly relationship. Thus the present invention provides for a hip stem assembly that permits both right and left hand versions with a common set of hip stem components.
• The technical advantages of the present invention further include the ability to correct surgical error or optimize the surgical variables such as leg length discrepancy. For example, according to yet another aspect of the present invention, a hip stem is provided including a hip stem component and a neck component. The neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone. Thus, the present invention provides for the replacement of the neck from the stem with the replacement neck having a different neck length than the replaced neck while replacing the neck with the stem in place. Thus the present invention provides for the correction of surgical error or optimization of a surgical variable such as leg length discrepancy.
• The technical advantages of the present invention also include the ability to correct head height at revision surgery due to implant subsidence. For example, according to yet another aspect of the present invention, a hip stem is provided including a stem component and a neck component. The neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone. Thus, the present invention provides for a replacement of the neck component with a replacement neck component with a different head-height than the initial neck component while having the stem component remain in place on the bone. Thus, the present invention provides for a correction of head height at revision surgery to adjust for implant subsidence.
• The technical advantages of the present invention include the ability to correct instability of the hip joint. Stability may be restored by moving the head proximally and/or increasing the offset to tighten the soft tissue. The corrections can also be made at revision surgery to address dislocations. For example, according to yet another aspect of the present invention, a hip stem is provided including a stem component as well as a plurality of neck components. One of the pluralities of neck components may have a first offset dimension and the second component have a greater offset dimension. Thus, the present invention provides for replacing the first neck component with a second neck component with greater offset while having the stem remain in place on the bone. Thus, the present invention provides for the correction of instability by moving the head proximally or increasing the offset to tighten the soft tissues.
• The technical advantages also include the ability to correct weak abductor function by increasing the offset of the hip stem, which increases the efficiency of the abductor muscles by increasing the moment arm of the abductor muscle action For example, according to yet another aspect of the present invention, a hip stem is provided including a stem component and a first neck component having a first offset and a second neck component having a greater offset than the first neck component. The neck component is adapted for removal from the femur without disturbing the fixation of the stem component to the bone. Thus, the present invention provides for replacing a first neck component with a second neck component of greater offset while the stem is in place in the bone. Thus, the present invention provides for correction of weak abductor function by increasing the offset of the hip stem.
• Other technical advantages of the present invention will be readily apparent to one skilled in the art from the following figures, descriptions and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in connection with the accompanying drawings, in which:
• FIG. 1 is a plan view of a modular hip stem in accordance with an embodiment of the present invention utilizing a tapered lock and screw;
• FIG. 1A is a partial plan view of an alternate embodiment of the present invention in the form of a modular hip stem with a tapered stem connection and a modular neck;
• FIG. 1B is a cross-sectional view ofFIG. 1 along theline1B-1B in the direction of the arrows;
• FIG. 2 is a top view of the modular hip stem ofFIG. 1;
• FIG. 3 is a plan view of a modular hip stem in accordance with another embodiment of the present invention utilizing dowel pins and a screw;
• FIG. 3A is a partial plan view of an alternate embodiment of the present invention in the form of a modular hip stem with a pinned stem connection and a modular neck;
• FIG. 4 is a top view of the modular hip stem ofFIG. 3;
• FIG. 5 is a plan view of a kit for performing hip orthopaedic surgery in accordance with yet another embodiment of the present invention;
• FIG. 6 is a plan view of a second stem component of a modular hip stem for use with the kit ofFIG. 5;
• FIG. 7 is a plan view of a neck component of a modular hip stem for use with the kit ofFIG. 5 including a through opening for utilizing a screw and having different offsets than the neck components ofFIG. 5;
• FIG. 8 is a plan view of a modular hip stem in accordance with another embodiment of the present invention utilizing dowel pins to provide for different version with the same stem;
• FIG. 9 is a plan view of a modular hip stem in accordance with yet another embodiment of the present invention utilizing a rectangular tapered lock and a screw;
• FIG. 9A is a cross-sectional view ofFIG. 9 along theline9A-9A in the direction of the arrows;
• FIG. 10 is a top view of the modular hip stem ofFIG. 9;
• FIG. 11 is an end view of the modular hip stem ofFIG. 9;
• FIG. 12 is a plan view of a modular hip stem in accordance with a further embodiment of the present invention utilizing a tapered lock;
• FIG. 13 is a plan view of a hip implant in accordance to another embodiment of the present invention including a modular hip stem similar to that ofFIG. 3;
• FIG. 14 is a top view of a modular hip stem with left handed proximal component with a neck extending posteriorly and a distal component;
• FIG. 15 is a top view of a modular hip stem with a right handed proximal component with a neck extending posteriorly, utilizing the distal component of the hip stem ofFIG. 14;
• FIG. 16 is a plan view of the modular hip stem ofFIG. 14 and15;
• FIG. 17 is a plan view of a modular stem in accordance with a further embodiment of the present invention in the form of a tibial tray assembly implanted in the tibia;
• FIG. 18 is a plan view of a further embodiment of the modular stem of the present invention in the form of a modular shoulder prosthesis implanted in the humerus and glenoid cavity;
• FIG. 19 is a plan view of a kit for performing joint arthoplasty including the modular stem of the present invention;
• FIG. 20 is a process flow diagram of a method of performing joint arthroplasty surgery in accordance with yet another embodiment of the present invention;
• FIG. 21 is a process flow diagram for a method of performing joint arthroplasty surgery according to a further embodiment of the present invention;
• FIG. 22 is a process flow diagram of a method of performing joint arthroplasty surgery in accordance with yet another embodiment of the present invention;
• FIG. 23 is a process flow diagram for a method of performing joint arthroplasty surgery according to a further embodiment of the present invention;
• FIG. 24 is a plan view of another kit for performing joint arthroplasty including the modular stem of the present invention;
• FIG. 25 is a plan view of a modular hip stem in accordance with a further embodiment of the present invention utilizing a location ring;
• FIG. 26 is a plan view of a body component of a modular hip stem in accordance with a further embodiment of the present invention utilizing a location ring; and
• FIG. 27 is a plan view of yet another kit for performing joint arthroplasty including the modular stem of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
• Embodiments of the present invention and the advantages thereof are best understood by referring to the following descriptions and drawings, wherein like numerals are used for like and corresponding parts of the drawings.
• According to the present invention and referring now toFIG. 1, an embodiment of the present invention is shown aship stem10.Hip stem10 is utilized for performing hip arthroplasty. The hip stem10 is designed to be fitted into acavity2 in thecanal4 of along bone6, for example, the femur. The hip stem10 includes astem component12 including adistal stem portion14 and aproximal body portion16. The hip stem10 further includes aneck component18 which, is as shown inFIG. 1, is fixedly connectable to thestem component12. Theneck component18 includes aproximal neck portion20 and adistal body portion22. Theneck component18 is adapted for removal from thefemur6 without disruption ofbone8 around thestem component12.
• To provide for the removal of the neck component without disturbing the fixation of thestem component12 to thebone8, thehip stem10 of the present invention may be adapted to provide all the support for the hip stem and fixation of thehip stem10 to thefemur6 with thestem component12. Thus, as shown inFIG. 1, thestem component12 is configured, preferably, to provide as much support as possible for thehip stem10 to thefemur6. For example, and as shown inFIG. 1, aportion24 of theproximal body portion16 of thestem component12 extends over a portion of thedistal body portion22 of theneck component18.
• While theportion24 of the proximal body portion of thestem component12 may be positioned anywhere around thefemur6 to provide additional support for thestem component12, it should be appreciated, and referring toFIG. 1, theportion24 may extend substantially around the periphery of thefemur6.
• For example, and as shown inFIG. 1, thestem component12 may include asleeve portion26 extending proximally from theproximal body portion16 of thestem component12. Thesleeve portion26 may extend laterally, medially, anteriorly, or posteriorly or a combination thereof. For example, and as shown inFIG. 1, thesleeve portion26 extends substantially aroundperiphery28 of thedistal body portion22 of theneck component18.
• As shown inFIG. 1, thedistal body portion22 of theneck component18 may receive thestem component12. To accommodate theneck component18, theproximal body portion16 of thestem component12 may define apocket32 in theproximal body portion16 for receiving theneck component18.
• As shown inFIG. 1, thehip stem10 may be configured to assist in the removal of theneck component18 from thefemur6 without disturbing the fixation of the stem component to thebone8, theneck component18 may be spaced from the femur. By spacing theneck component18 from the femur, theneck component18 may be removed without disturbing the fixation of thestem component12 to the bone.
• As shown inFIG. 1, thedistal body portion22 of theneck component18 is removably secured to theproximal body portion16 of thestem component12. Thedistal body portion22 and theproximal body portion16 may be removably secured to each other in any reasonable manner.
• For example, and as shown inFIG. 1, theproximal body portion16 of thestem component12 includes aperiphery34 of theproximal body portion16. Aportion36 of theperiphery34 is generally planer. Similarly, thedistal body portion22 of theneck component18 defines aperiphery38 of the distal body portion. Aportion40 of theperiphery38 is generally planer. Theneck planer portion40 and thebody planer portion36 are in contact with each other. The contact of theneck planer portion40 and thebody planer portion36 provide for a stable support of theneck component18 onto thestem component12.
• For simplicity and as shown inFIG. 1, thestem component12 defines alongitudinal axis42 of thestem component12. For simplicity and to provide for strength and rigidity, theneck planer portion40 and thebody planer portion36 are generally normal or perpendicular to thelongitudinal axis42.
• As shown inFIG. 1, thehip stem10 may include a connector in the form of, for example a fastener, for example ascrew44 to connect theneck component18 to thestem component12. As shown inFIG. 1, theconnector44 may be in the form of, for example, a screw.
• Neck component18 may be connected to thestem component12 in many different ways within the various embodiments of the present invention. For example and as shown inFIG. 1, thedistal body portion22 of theneck component18 may include aprotrusion46 extending downwardly from theneck planer portion40.Protrusion46 may have any suitable shape, and may as shown inFIG. 1 have a generally circular cross-section and be tapered defining an included angle α.Stem component12 may, in order to receive theprotrusion46 of theneck component18, define anaperture48 formed in theproximal body portion16 of thestem component12.Aperture48 may have a contour matching that of theprotrusion46 for receiving the protrusion therein. It should be appreciated that the angle α may be sufficiently small to provide for a soft self-locking feature between theprotrusion46 and theaperture48.
• For a self-locking taper the angle α should be defined by the formula;$\mathrm{Tan}\frac{\left(\alpha /2\right)<\mathrm{<figure-callout\; label="\mu "\; filenames="US20070050039A1-20070301-D00000.png,US20070050039A1-20070301-D00001.png"\; state="\{\{state\}\}">\mu </figure-callout>}}{2}$
  where α=coefficient of friction
• • μ=included angle
• Referring now toFIG. 1-B, theprotrusion46 and theaperture48 are shown in cross-section. As shown inFIG. 1-B, theprotrusion46 has a circular cross-section defined by protrusion diameter PD.
• As shown inFIG. 1, theconnector44 may be in the form of a screw. Thescrew44 may be any suitable screw and may, as shown inFIG. 1, have a flat head and be in the form of a socket-headed cap screw.Connector44 may be received by theneck component18 by aconnector opening50 formed in theneck component18 and positioned aboutlongitudinal axis42. Theconnector44 may be received into thestem component12 throughstem component aperture52. Thestem component aperture52 may includeinternal threads54 that mate withexternal threads56 formed on the connector orscrew44.
• The hip stem10 including thestem component12, theneck component18 as well as thescrew44 may be made of any suitable durable material. For example, thestem component12, theneck component18 and theconnector44 may be made of, for example, a metal, a plastic or a composite. The materials from which the components of thehip stem10 are manufactured preferably are materials that are compatible with the human body. For example, if thestem component12,neck component18, or the connector or screw44 are made of a metal, the components may be made of, for example, a cobalt chromium alloy, a stainless steel alloy, or a titanium alloy.
• Thestem component12 may have any suitable shape capable of insertion into thecanal4 of thefemur6. For example, thestem component12 may include astem periphery58 having a shape similar to that of the broach or rasp used to form thecavity2 in thecanal4 of the long bone orfemur6. Theproximal body portion16 of thestem component12 may, as shown inFIG. 1, have a larger cross-section than that of thedistal stem portion14 to conform with the corresponding shape of thenatural femur6.
• Theneck component18 of thehip stem10 may have any suitable shape capable of mating with thestem component12 and capable of providing support for the ball orhead60 which may be placed onexternal taper62 formed onneck64 of theneck component18. It should be appreciated that thehip stem10 may be integral with theneck component18.
• As shown inFIG. 1, hip stem or orthopaedic implant stem10 is used for performing joint arthroplasty. A portion of the orthopaedic implant stem10 may be fitted tocavity2 in thecanal4 oflong bone6. The orthopaedic implant stem10 includes a stem component orcanal element12 havingexternal stem periphery58. Thecanal element12 has afirst end15 for insertion into the cavity and anopposed connection end17. Thecanal element12 has pocket orrecess32 extending from opposed connection end17 of thecanal element12. Therecess32 has aninternal periphery23. Thecanal element12 also hasexternal periphery58 spaced outwardly from theinternal periphery23 of therecess32. The orthopaedic implant stem10 further includes neck component orbody element18 that may be fixedly connected to thecanal element12. Distal body portion or firstdistal body portion22 of theneck component18 may be inserted into therecess32 of thecanal element12 when theneck component18 is fixedly connected to thecanal element12.External periphery78 of thefirst portion22 of theneck component18 is spaced inwardly from theexternal periphery58 of thecanal element12 when theneck component18 is fixedly connected to thecanal element12 so that theneck component18 may be removed from thelong bone6 without disturbing the fixation of thecanal element12 to thelong bone6.
• As shown inFIG. 1, thedistal body portion22 of theneck component18 may have any suitable shape and typically has a shape compatible for placement within the recess orpocket32 formed in theproximal body portion16 of thestem component12. For example, thedistal body portion22 may, as shown inFIG. 2, have a generally rectangular shape defined by neck body width NBW and neck body length NBL.
• Referring now toFIG. 1A, another embodiment of the present invention is shown as hip stem10A. The hip stem10A is similar to thehip stem10 ofFIG. 1, except that theneck component18A is of a modular construction or is made from more than one piece. For example, as shown inFIG. 1A, theneck component18A includes adistal body component22A and aproximal neck component20A. Theproximal neck component20A may be secured to thedistal body component22A in any suitable fashion.
• As shown inFIG. 1A, theproximal neck component20A includes anexternal taper21A that mates with acavity23A formed in thedistal body component22A. It should be appreciated that the components forming theneck component18A may be threadably attached, press-fit attached or have a bayonet lock or any type of connector. The hip stem10A further includes astem component12A which is similar to thestem component12 and includes adistal stem portion14A and aproximal body portion16A.
• Hip stem10 of the present invention, as shown inFIG. 1 andFIG. 2, may be utilized for both cemented and cementless hip arthroplasty. For example, thehip stem10 may be used with a femur having a cavity prepared for cement with the cement being positioned between thefemur6 and thehip stem10. Thecavity2 of thefemur6 may alternatively be prepared such that thestem periphery58 may directly connect with the periphery of thecavity2. It should be appreciated that whether thehip stem10 uses cemented or cementless construction, theneck component18 may be removed from thestem component12 without disruption of the bone implant ingrowth.
• According to the present invention and referring now toFIG. 3 and4, yet another embodiment of the present invention is shown aship stem110.Hip stem110 is similar to thehip stem10 ofFIG. 1 and2 and may, in fact, be made of similar materials with generally similar shapes. Thehip stem110, however, is different from thehip stem10 ofFIGS. 1 and 2.
• For example and as shown inFIGS. 3 and 4, thehip stem110 includes astem component112 somewhat similar to thehip stem component12 ofFIGS. 1 and 2. The hip stem110 further includes aneck component118 somewhat similar to theneck component18 ofFIGS. 1 and 2. The hip stem110 further includes aconnector144 which is different thanconnector44 of thehip stem10 ofFIGS. 1 and 2.
• For example, as shown inFIGS. 3 and 4, theconnector144 includes ascrew164 similar to thescrew44 of thehip stem10 ofFIGS. 1 and 2. In addition to thescrew64, theconnector144 further includes a pin, for example,first pin166. Thehip stem110, it should be appreciated, may be manufactured with asolitary pin166 but may, as shown inFIGS. 3 and 4, further include asecond pin168. Thepins166 and168 as well as thescrew164 serve to form theconnector144. Theconnector144 is used to connect theneck component118 to thestem component112.
• Thefirst pin166 and thesecond pin168 may, for simplicity as shown inFIGS. 3 and 4, be substantially the same. For example, thepins166 and168 may be cylindrical. For example, thefirst pin166 and thesecond pin168 may be defined by a pin diameter PD and a pin length PIL. Thefirst pin166 and thesecond pin168 may be made of any suitable durable material and may, for example, be made of a metal. If made of a metal, thefirst pin166 and thesecond pin168 may, for example, be made of a material compatible with a human body. For example, a cobalt chromium alloy, a stainless steel alloy, or a titanium alloy.
• Thestem component112 may, as is shown inFIGS. 3 and 4, have adistal stem portion114 and aproximal body portion116.Internal threads156 may be formed onproximal body portion116 to mate withexternal threads148 formed on thescrew164. Theproximal body portion116 of thestem component112 may define a first pin stem opening170 for receiving thefirst pin166 as well as a second pin stem opening172 for receiving thesecond pin168. Thepins166 and168 may be matingly fitted to theopenings172 and170. Theproximal body portion116 may further include asleeve portion126 which forms apocket132 for receiving theneck component118. Theneck component118 may include ascrew opening150 for receiving thescrew164. Theneck component118 may further define a first pin neck opening174 for receiving a portion of thefirst pin166 as well as a second pin neck opening176 for receiving thesecond pin168.
• It should be appreciated that to minimize the number of loose parts thefirst pin166 and thesecond pin168 may be fixably secured to one of theneck component118 or thestem component112. It should be appreciated that thefirst pin166 and thesecond pin168 would then be slidably secured to the other of thestem component112 and theneck component118.
• Theneck component118 includes adistal body portion122 as well as aproximal neck portion120. Theproximal neck portion120 may define anexternal taper162 which matingly receives a ball orhead160.
• Referring now toFIG. 3A, yet another embodiment of the present invention is shown as hip stem110A. The hip stem110A is similar to thehip stem110 ofFIGS. 3 and 4, except that theneck component118A is different than theneck component118 of thehip stem110 ofFIGS. 3 and 4 in that theneck component118A is modular or made of more than one component. For example, as shown inFIG. 3A, theneck component118A includes adistal body component122A which is connectable to aproximal neck component120A. It should be appreciated that thedistal body component122A and theproximal neck component120A may be connected to each other in any suitable fashion, for example they may be threadably connected, have a bayonet connection, have a press-fit connection or, as is shown inFIG. 3A, have a tapered connection. For example, thedistal body component122A may include atapered cavity123A for receiving atapered protrusion121A extending from theproximal neck component120A. Hip stem110A further includes astem component112A which together with theneck assembly118A forms thehip stem110A.
• Referring now toFIGS. 5, 6 and7, yet another embodiment of the present invention is shown asKit200. TheKit200 is for use in performing a primary or a revision arthroplasty. TheKit200 includes afirst stem component212, afirst neck component218, and asecond neck component318.
• Thefirst stem component212 includes adistal stem portion214 and aproximal body portion216. Thefirst stem component212 may have any suitable shape and may have a shape somewhat similar to thestem component12 ofFIG. 1. As shown inFIG. 5, thefirst stem component212 may include apocket232 formed bysleeve226 of thestem212. Thepocket232 is adapted for receiving thefirst neck component218 or, alternatively, thesecond neck component318.
• As shown inFIG. 5, to secure theneck components218 and318 to thefirst stem component212, thestem component212 may include an aperture252 extending inwardly fromplaner face236 of thepocket232. Internal threads254 may be formed in aperture252. The internal threads254 may cooperate withexternal threads256 formed on screw244.
• Thefirst neck component218 may be similar to theneck component18 of thehip stem10 ofFIGS. 1 and 2. Thefirst neck component218, however, does not include a protrusion such as theprotrusion46 of theneck component18 ofFIGS. 1 and 2.First neck component218 includes adistal body portion222 and aproximal neck portion220 extending from thedistal body portion222.
• Thedistal body portion222 defines aplaner face240 for cooperation with theplaner face236 of thefirst stem component212. Thedistal body portion222 further defines aperiphery278 which mates withsleeve226 of thefirst stem component212. Thedistal body portion222 further defines anopening250 for receiving the screw244. Theproximal neck portion220 defines aneck264 from which extends anexternal taper262. A head260, as shown in phantom, may be fitted onto theexternal taper262.
• Thefirst neck component218 defines a height H1, a neck length NL1 and a neck angle α NA1. The combination of neck height, length, and angle assist in positioning the head260 with respect to thestem212. Unique patient anatomies require that the head260 be put in the proper position. By utilizing thekit200 of the present invention, various neck components can be utilized to provide for variations in the position of the head.
• For example, and as shown inFIG. 5, thekit200 further includes asecond neck component318. Thesecond neck component318 includes different dimensions than thefirst neck component218 so that the head may be positioned in a different location than that obtained if thefirst neck component218 is used.
• For example, and as shown inFIG. 5, thesecond neck component318 includes adistal body portion322 and aproximal neck portion320.Distal body portion322 includes aplaner face340 for cooperation with theplaner face236 of thestem212. Thedistal body portion322 further defines aperiphery378 for mating withsleeve226 of thestem214. Thedistal body portion322 defines anopening350 receiving the screw244.
• Theproximal neck portion320 defines aneck364 which is connected to thedistal body portion322. Anexternal taper362 extends from theneck364. As shown inFIG. 5, the periphery366 of thedistal body portion322 and theplaner face340, as well as theopening350 of thesecond neck component318 have configurations compatible with theplaner face340, theopening350, and the periphery266 of thedistal body portion322 of thefirst neck component218 in order that thefirst neck component218 and thesecond neck component318 may be selectively used with thefirst stem component212.
• As shown inFIG. 5, thesecond neck component318 may include a height H2 which is different than the height Hi of thefirst neck component218. Similarly, theproximal neck portion320 of thesecond neck component318 may define a neck length NL2 which is different than neck length NL1 of theproximal neck portion220 of thefirst neck component218. Further, the proximal neck portion of thesecond neck component318 may define a neck angle α NA2 which is different than the neck angle α NA1 of theproximal neck portion220 of thefirst neck component218. It should be appreciated that different neck components may be accomplished where only one of the neck height, neck length, and neck angle are different from each other.
• Referring again toFIG. 5 and according to the present invention akit201 for use in performing revision surgery on thecavity2 in thecanal4 of thelong bone6 is shown. Thecavity2 extends from a resectedplane11 of thelong bone6. Thekit20 includes first stem component orcanal component212 having anexternal periphery221. A portion of thecanal component212 may be fitted to thecavity2 in thecanal4 of thelong bone6. Thecanal component212 includes distal stem portion orcanal portion214 having afirst end215 for insertion into the cavity and an opposedsecond end217. Thecanal component212 further includes asleeve portion226 extending from thesecond end217 of thecanal portion212. Thesleeve portion226 has an internal periphery219 defining pocket orinternal cavity232. Thesleeve portion226 also has anexternal periphery227. Thekit201 also includes first neck component or firstjoint component218 removably connectable to thecanal component212. The firstjoint component218 has a proximal neck portion orbody portion220 and a distal body portion orconnection portion222. Theconnection portion222 of the firstjoint component218 has anexternal periphery278. A portion of theexternal periphery278 of theconnection portion222 of the firstjoint component218 may be fitted into theinternal cavity232 of thesleeve portion226 of thecanal component212.
• Thekit201 also includes a second neck component or a secondjoint component318 that is removably connectable to thecanal component212. The secondjoint component318 has a proximal neck portion orbody portion320 and distal body portion orconnection portion322. Theconnection portion322 of the secondjoint component318 has anexternal periphery378. A portion of theexternal periphery378 of theconnection portion322 of the secondjoint component318 is fitted into theinternal cavity232 of thesleeve portion226 of thecanal component212 so that theexternal periphery378 of theconnection portion322 of the firstjoint component218 is spaced inwardly from theexternal periphery227 of thesleeve portion226 of thecanal component212 when the firstjoint component218 is fixedly connected to thecanal component212 so that the firstjoint component218 may be removed from thelong bone6 and replaced with the secondjoint component318 without disturbing the fixation of thecanal component212 to thelong bone6.
• Thekit201 may, as shown inFIG. 5, be configured such that thecanal component212, the firstjoint component218, and/or the secondjoint component318 define resection rings231,233 and333, respectively, on a surface of the component. The resection rings231,233 and333 may be used to align the component axially with theresection plane11.
• Thefirst resection ring231 as shown inFIG. 5 may be visually distinguishable from the exterior periphery orsurface227 of thecanal component212 adjacent to thering231. It should be appreciated that any or all of the resection rings231,233 and333 may be invisible.
• Thekit201, may as shown inFIG. 5, be configured such that a portion of thecanal component212 is extendable over a portion of at least one of the firstjoint component218 or the secondjoint component318.
• Thekit201 may, as shown inFIG. 5, be configured such that the firstjoint component218 and the secondjoint component318 have at least one dimension that is different from each other.
• Thekit201 may, as shown inFIG. 5, be configured such that aportion236 of theexternal periphery227 of thecanal component212 is generally planar. Further aportion240 of theexternal periphery278 of theconnection portion222 of the firstjoint component218 may, as shown, be generally planar. Theportion236 of theexternal periphery227 of thecanal component212 and theportion240 of theexternal periphery278 of theconnection portion222 of the firstjoint component218 may, as shown, contact each other.
• Thekit201 may, as shown inFIG. 5, also include a connector244 to connect thejoint component218 to thecanal component212. For example, the connector244 may be in the form of a screw or as shown inFIG. 13 as a pin.
• Thekit201 may alternately (seeFIG. 1) be constructed such that the firstjoint component218 may include a protrusion. To cooperate with the protrusion, thecanal component212 may define an aperture for receiving the protrusion. The protrusion and the aperture may have any suitable shape and may, for example, be cylindrical or tapered.
• It should be appreciated that thecanal component212 may alternately include a protrusion (not shown). The firstjoint component218 may then include an aperture for receiving the protrusion.
• Thekit201 may (seeFIG. 16) further include a prosthetic component adapted for implantation to a second bone. The prosthetic component may cooperate with the firstjoint component218. Further at least a portion of thebody portion220 of the firstjoint component218 may include an articulation surface for articulation with the prosthetic component.
• Thekit201 may also include a prosthetic component for fixed implantation to a second bone and for cooperation with the first joint component. Thekit201 may also include a bearing component positionable between the first joint component and the prosthetic component. The bearing component may articulate with the first joint component and/or the prosthetic component.
• As shown inFIG. 5, the firstjoint component218 may be in the form of, for example, a hip neck. Thecanal component212 may correspondingly be in the form of a hip stem. Further the kit may include hip head260 for attachment to thehip neck218 and an acetabular cup (seeFIG. 16) for articulating cooperation with the hip head260.
• Referring again toFIG. 5, thecanal component212 may define alongitudinal axis235 and the internal periphery219 and theexternal periphery227 of the sleeve portion of the canal component may also define a wall thickness WT2 therebetween. The wall thickness WT2 may, as shown, be generally uniform in a plane normal to thelongitudinal axis235 of thecanal component212. Theexternal periphery278 of theconnection portion222 of the firstjoint component218 may be adapted to closely conform to the internal periphery219 of thesleeve portion226 of thecanal component212.
• Thecanal component212 may (seeFIG. 18) be in the form of a humeral stem and the firstjoint component218 may be in the form of a humeral neck. Thekit201 may also include a humeral head for connection with the humeral neck.
• Referring now toFIG. 5 the kit may also include connector244 to connect at the firstjoint component218 or the secondjoint component318 to thecanal component212. The connector may be in the form of a screw or a pin (SeeFIG. 16).
• As shown inFIG. 6, thekit200 may further include asecond stem component312. Thesecond stem component312 may be different than thefirst stem component212 and may include adistal stem portion314 that is longer, has a different angle, is narrower, or is larger or smaller in diameter than thedistal stem portion214 of thefirst stem component212.
• As shown inFIG. 6, thesecond component312 may define apocket332 which has generally the same size and shape as thepocket232 of thefirst stem component212 such that either thefirst neck component218 orsecond neck component318 may be compatible with thesecond stem component312 as well as with thefirst stem component212. For example, thepocket332 may be defined by thesleeve326 extending fromplaner surface336. Thesecond stem component312 may include aproximal body portion316 that defines anaperture352 defininginternal threads356 which mate withexternal threads256 of the screw244.
• Referring now toFIG. 7, theKit200 may further include athird neck component418. Thethird neck component418 includes adistal body portion422 and aproximal body portion420. Thedistal body portion422 of thethird neck component418 may defineplaner surface440 andperiphery478. Thesurface440 andperiphery478 which as shown inFIG. 7 are selected such that thethird neck component418 may be compatible and fit in thepocket232 of thefirst stem212.
• Thedistal body portion422 defines anopening450 for receiving the screw244. Theproximal neck portion420 defines aneck464 extending from thedistal body portion422 and anexternal taper462 that extends from theneck464 and that is adapted for cooperation with a ball or head, forexample head460. It should be appreciated that theexternal taper462, ofthird neck component418 theexternal taper362 of thesecond neck component318, as well as theexternal taper262 of thefirst neck component218 may have similar sizes and shapes, such that the same head or similar heads may be accommodated by all of the associated tapers of the associated neck components.
• As shown inFIG. 7 thethird neck component418 defines a neck length NL3, a neck angle α NA3, and a neck height H3. It should be appreciated that at least one of the neck height H3, the neck length NL3 or the neck angle α NA3 may be different than the corresponding dimension for thefirst neck component218 or thesecond neck component318.
• Referring now toFIG. 8, yet another embodiment of the present invention is shown aship stem510. Thehip stem510 is different than thehip stem110 ofFIGS. 1 and 2 in that thehip stem510 provides for two assembly positions. For example, as shown inFIG. 8, hip stem510 may include ananterior assembly position580 as is shown in solid and aposterior assembly position582 as is shown in phantom.
• It should be appreciated that as is shown inFIG. 8, thehip stem510 may be a right hip stem. It should be appreciated that for a left hip stem, the anterior assembly position and the posterior assembly position would be reversed.
• According to the present invention, and as shown inFIG. 8, thehip stem510 includes astem component512 as well as aneck component518. Thestem component512 may be similar to thestem component12 ofFIGS. 1 and 2, except that thestem component512 includes a plurality of mounting positions for mounting theneck component518 onto thestem component512 in a plurality of positions. For example, as shown inFIG. 8, thestem component518 includes a first stem opening570 for cooperating withfirst pin566.
• Thestem component512 further includes a second pin stemanterior opening571 for receiving thesecond pin568. When thesecond pin568 is positioned in the second pin stemanterior opening571, theneck component518 is positioned with respect to thestem component512 such that thehip stem510 is in theposterior assembly position582 as shown in phantom.
• Thestem component512 further includes a second pin stemposterior opening572. The second pin stemposterior opening572 is adapted for likewise receiving thesecond pin568. When thesecond pin568 is positioned in the second pin stemposterior opening572, theneck component518 is aligned with thestem component512 such that thehip stem510 is assembled into theanterior assembly position580 is shown in solid.
• Proximal body portion516 of thestem component512 includes asleeve portion526 for cooperation with bone and or cement.
• Theneck component518 includes adistal body portion522 defining aperiphery578 thereof. Theperiphery578 of thedistal body portion522 is fitted within cavity orpocket532 formed in thestem component512 by thesleeve portion526. Thedistal body portion522 of theneck component518 includes a first pin neck opening574 as well as a secondpin neck opening576. The firstpin neck opening574 cooperates with thefirst pin566 while the secondpin neck opening576 cooperates with thesecond pin568.
• Aneck564 extends from thedistal body portion522 of theneck component518. Anexterior taper562 extends from theneck564 and serves to receivehead560. Theneck564 andexterior taper562 form theproximal neck portion520 of theneck component518. As can be seen by simply rotating thecomponent518 after removing thesecond pin568 from thestem component512, theneck component518 may be rotated aboutfirst pin566 in the direction ofarrows584 to eitheranterior assembly position580 orposterior assembly position582.
• Referring now toFIGS. 9 and 10, yet another embodiment of the present invention is shown aship stem610. The hip stem610 ofFIGS. 9, 10 and11 is different than thehip stem10 ofFIGS. 1 and 2 in that thehip stem610 includes anexternal protrusion646, which is different than theexternal protrusion46 of thehip stem10 in that theexternal protrusion646 is rectangular rather than circular in cross-section. For example, and as shown inFIG. 9, thehip stem610 includes astem component612 as well as aneck component618.
• Thestem component612 includes adistal stem portion614 for cooperation with thecavity2 formed in thecanal4 of thefemur6. The stem component further includes aproximal body portion616 which defines apocket632 for receiving theneck component618. Anopening652 formed in thepocket632 includesinternal threads656 for cooperation withexternal threads648 formed on thescrew644. Theproximal body portion616 ofstem component612 includes anaperture648 formed therein for receiving theexternal protrusions646 extending fromneck component618.
• Referring now toFIG. 9-A, theexternal protrusion646 and theaperture648 are shown in cross-section. Theaperture648 and theexternal protrusion646 are defined by a protrusion width PW and a protrusion length PL which defines a generally rectangular cross-section of theexternal protrusion646, and correspondingly theaperture648.
• Referring again toFIG. 9, theexternal protrusion646 further defines a protrusion height PH extending alonglongitudinal axis642 of thehip stem610.
• Referring toFIGS. 10 and 11, theneck component618 includes adistal body portion622 and aproximal neck portion620 extending from thedistal body portion622.Stem component612 includes asleeve portion624 which defines apocket632 for receivingperiphery678 of thedistal body portion622 of theneck component618. Theneck component618 includes thedistal body portion622 and theproximal neck portion620. Theproximal neck portion620 includes aneck664 and anexternal taper662 extending from theneck664. Ahead660 may mate withexternal taper662.
• Theexternal protrusion646 may, as shown inFIGS. 10 and 11, be tapered and define first included angle α SQ1 and second included angle αSQ2
• Referring now toFIG. 12, another embodiment of the present invention is shown aship stem710. Thehip stem710 is different than thehip stem10 ofFIGS. 1 and 2 in that thehip stem710 relies solely on a self-locking tapered connection to combine the components of thehip stem710.
• For example, and as shown inFIG. 12, thehip stem710 includes astem component712 as well as aneck component718. Thestem component712 includes adistal stem portion714 and aproximal body portion716. Theproximal body portion716 defines aplaner surface736 from which acavity748 extends.
• Theneck component718 includes adistal body portion722 and aproximal neck portion720 extending from thedistal body portion722. Thedistal body portion722 includes aprotrusion746 extending fromplaner surface740 of thedistal body portion722.
• Theprotrusion746 is tapered and defines an included angle β of, for example, two to twenty degrees (2°-20°) for a self locking taper, the angle β is defined by equation:
  tan β/2<μ
  Where: β=coefficient of friction
• • β=included angle
• Theprotrusion746 cooperates with thecavity748 to lock theneck component718 to thestem component712.
• Thedistal body portion722 fits withinpockets732 formed by thesleeve portion726 of theproximal body portion716 of thestem component712.
• Theproximal neck portion720 includesneck764 from whichexternal taper762 extends. Thehead760 is fitted ontoexternal taper762.
• According to the present invention and referring now toFIG. 13, yet another embodiment of the present invention is shown asprosthesis800. Theprosthesis800 as shown inFIG. 13 is in the form of a hip prosthesis. Theprosthesis800 includes a hip stem810. The hip stem810 is similar to thehip stem110 ofFIGS. 3 and 4. The hip stem810 includes astem component812 as well as aneck component818.
• Thestem component812 may be similar to thestem component112 ofFIGS. 3 and 4. Thestem component812 includes adistal stem portion814 adapted to fit withincavity2 of thecanal4 offemur6. The stem component further includes aproximal body portion816 extending from thedistal stem portion814 of thestem component812. Theproximal body portion816 includes anaperture852 extending inwardly frominner face836 of theproximal body portion816 of thestem component812.Internal threads854 are formed in theaperture852. Theinternal threads854 cooperate withexternal threads848 formed onscrew851.
• Theneck component818 is, as is shown inFIG. 13, connected to thestem component814 by any suitable connector, for example, byconnector844. Theconnector844, as is shown inFIG. 13 includes thescrew851, as well as, afirst pin866. Theconnector844 may further include asecond pin868 spaced from and parallel to thefirst pin866.
• Theneck component818 includes adistal body portion822 and aproximal neck portion820 extending from thedistal body portion822. Thedistal body portion822 includes anaperture850 for receiving thescrew851. Thedistal body portion822 further includes a first pin neck opening874 for cooperating with thefirst pin866 and a second pin neck opening876 for cooperating with thesecond pin868. Thedistal body portion822 further defines aplanar face840 for cooperation with aplanar face836 of thestem component812.
• Theproximal body portion816 of thestem component812 includes a first pin stem opening870 for cooperation with thefirst pin866 and a second pin stem opening872 for cooperation with thesecond pin868. Theproximal body portion816 of thestem component812 includes asleeve portion826 defining apocket832 for receivingperiphery878 of thedistal body portion822 of theneck component818.
• Theproximal neck portion820 of theneck component818 includes aneck864 as well asexternal taper862 extending from theneck864.
• In addition to the hip stem810, theprosthesis800 further includes ahead860 which matingly fits onexternal taper862 of theneck component818. Theprosthesis800 further includes anacetabular cup886 for cooperation withacetabulum9 of the patient. Theacetabular cup886 may include a feature in the form of, for example, a porouscoated surface888 for promoting boney in-growth between theacetabulum9 and theacetabular cup886. Theprosthesis800 may include abearing890 positioned between theacetabular cup886 and thehead860. It should be appreciated that theacetabular cup886 may directly cooperate with thehead860.
• It should be appreciated that the hip stem810,head860,acetabular cup886, and bearing890 may be made of any suitable durable material. The hip stem810 including thedistal stem portion814, theneck component818, as well aspins866 and868 and thescrew864, may all be made of a suitable durable material. The materials for the components of theprosthesis800 may, for example, be made of a plastic, a metal, or a composite. The material for which the prosthesis is made preferably is compatible with the human anatomy. Theprosthesis800, if made of a metal may for example be made of a cobalt chromium alloy, a stainless steel alloy, or a titanium alloy.
• The bearing890 of theprosthesis800 may for example, be made of a metal, a ceramic, or a plastic. Thehead860 may be made of a metal, or a ceramic.
• According to the present invention and referring now toFIGS. 14-16, yet another embodiment of the present invention is shown asprosthesis800A. Theprosthesis800A is shown inFIG. 14 in the form of a hip prosthesis. Theprosthesis800A includes ahip stem810A. The hip stem810A is similar to the hip stem810 ofFIG. 13 except the hip stem810A provides for posterior version for hip stems for both the right leg and the left leg of the patient. The hip stem810A includes astem component812A as well as aright neck component818A as shown inFIG. 14 and aleft neck component819A as shown inFIG. 15.
• As shown inFIG. 16, thestem component812A may be similar to thestem component812 ofFIG. 13. Thestem component812A includes adistal stem portion814A adapted to fit withincavity2 of thecanal4 offemur6. Thestem component812A further includes aproximal body portion816A extending from thedistal stem portion814A of thestem component812A. Theproximal body portion816A includes anaperture852A extending inwardly frominner face836A of theproximal body portion816A of thestem component812A.Internal threads854A are formed in theaperture852A. Theinternal threads854A cooperate withexternal threads848A formed on screw851A.
• Theright neck component818A and theleft neck component819A are thus alternatively connected to the stem component182A. Thecomponents818A and819A may be connected to thestem component812A by any suitable connector.
• Theright neck component818A is shown connected to thestem component812A inFIG. 16. It should be appreciated that theleft neck component819A is likewise, similarly connected to thestem component812A.
• Theright neck component818A is, as is shown inFIG. 16, connected to thestem component814A by, for example,connector844A. Theconnector844A, as is shown inFIG. 16 includes the screw851A, as well as, afirst pin866A. Theconnector844A may further include asecond pin868A spaced from and parallel to thefirst pin866A.
• Theright neck component818A includes adistal body portion822A and aproximal neck portion820A extending from thedistal body portion822A. Thedistal body portion822A includes anaperture850A for receiving the screw851A. Thedistal body portion822A further includes a firstpin neck opening874A for cooperating with thefirst pin866A and a secondpin neck opening876A for cooperating with thesecond pin868A. Thedistal body portion822A further defines aplanar face840A for cooperation with aninner face836A of thestem component812A.
• Theproximal body portion816A of thestem component812A includes a first pin stem opening870A for cooperation with thefirst pin866A and a second pin stem opening872A for cooperation with thesecond pin868A. Theproximal body portion816A of thestem component812A includes asleeve portion826A defining apocket832A for receivingperiphery878A of thedistal body portion822A of theright neck component818A.
• As shown inFIG. 14, theproximal neck portion820A of theright neck component818A includes aright neck864A as well as a rightexternal taper862A extending from theright neck864A. Theright neck864A extends posteriorly from thedistal body portion822A of theright neck component818A at an angle θθ of, for example, 10 to 40 degrees. The posterior extension is intended to mimic the geometry of the natural right femur.
• As shown inFIG. 15, theproximal neck portion821A of theleft neck component819A includes aleft neck865A as well as a leftexternal taper863A extending from theleft neck865A. Theleft neck865A extends posteriorly from the distal body portion823A of theleft neck component819A at an angle θθθ of, for example, 10 to 40 degrees. While as shown inFIG. 15 theneck865A extends downwardly, it should be appreciated that shape when placed in a left femur will extend posteriorly. The posterior extension is intended to mimic the geometry of the natural left femur.
• It should be appreciated that both theright neck component818A ofFIG. 14 and theleft neck component819A ofFIG. 15 may be used with theidentical stem component812A. This may be accomplished by providing the leftexternal taper863A of theleft neck component819A with identical dimensions to that of the rightexternal taper862A of theright neck component818A. Thus both the rightexternal taper862A and the leftexternal taper863A may mate with the internal taper of thestem component812A.
• Referring again toFIG. 16, in addition to hip stem810A, theprosthesis800 further includes ahead860A, which matingly fits onexternal taper862A or863A of either of theneck components818A and819A respectively. Theprosthesis800A further includes an acetabular cup886A for cooperation withacetabulum9 of the patient. The acetabular cup886A may include a feature in the form of, for example, a porouscoated surface888 for promoting boney in-growth between theacetabulum9 and the acetabular cup886A. Theprosthesis800A may include abearing890A positioned between the acetabular cup886A and thehead860A. It should be appreciated that the acetabular cup886A may directly cooperate with thehead860A.
• It should be appreciated that the hip stem810A,head860A, acetabular cup886A, and bearing890A may be made of any suitable durable material. The hip stem810A including thedistal stem portion814A, theneck components818A and819A, as well as thepins866A and868A and thescrew864A, may all be made of a suitable durable material. The materials for the components of theprosthesis800A may, for example, be made of a plastic, a metal, or a composite. The material for which the prosthesis is made preferably is compatible with the human anatomy. Theprosthesis800A, if made of a metal may, for example, be made of a cobalt chromium alloy, a stainless steel alloy, or a titanium alloy.
• Thebearing890A of theprosthesis800A may for example, be made of a metal, a ceramic, or a plastic. Thehead860A may be made of a metal, or a ceramic.
• According to the present invention and referring toFIG. 17 another embodiment of the present invention is shown asprosthesis900. Theprosthesis900 as shown inFIG. 17 is for use in the knee joint. Theorthopedic prosthesis900 as shown inFIG. 16 includes atibial component910, abearing990 and afemoral component992.
• Thetibial component910 for theprosthesis900 is for use withtibia5. Thetibial component910 includes ajoint component918 and astem component912. Thestem component912 fits within theintramedullary canal7 of thetibia5. Thestem component912 includes adistal stem portion914 as well as aproximal body portion916.Proximal body portion916 of thestem component912 defines apocket932 formed fromsleeve portion926 of theproximal body portion916. Aconnector944 is used to connect thestem component912 to thejoint component918.
• Thejoint component918 includes anarticulation portion920 and adistal body portion922 extending from thearticulation portion920. Thedistal body portion922 of thejoint component918 defines aprotrusion946 which cooperates with thepocket932 formed by thesleeve926 of thestem component912.
• Theconnector944 connects thejoint component918 to thestem component912. Theconnector944 may have any suitable shape and may, as shown inFIG. 17, include ascrew964 as well as afirst pin966 and asecond pin968. Thepins966 and968 engage with thejoint component918 and with thestem component912. Thescrew964 includesexternal threads948 which cooperate withinternal threads954 formed on theproximal body portion916 of thestem component912. As shown inFIG. 17, thearticulation portion920 of thejoint component918 extends transversely or perpendicular tolongitudinal axis942 of thestem component912 substantially past thestem component912.
• Thesleeve926 may extend, as shown inFIG. 17, up against the taper of thepocket932. Thesleeve926 may, as shown inFIG. 17, extend out transversely from thelongitudinal axis942 and define aplaner surface936 of thestem component912. Similarly, thejoint component918 may include aplaner portion940 extending transversely from thelongitudinal axis942. Theplaner portions936 and940 may cooperate with each other to support and form thestem component912.
• As shown inFIG. 17, theorthopedic prosthesis900 further includes afemoral component992 connected tocavity2 formed incanal4 of thefemur6. Thefemoral component992 cooperates with thejoint component918 of thestem912. Thefemoral component992 may cooperate directly with thetibial component910. Theorthopedic prosthesis900 may further include abearing990 supported by the articulatingportion920 of thejoint component918. Thebearing990 may, for example, be made of a pliable material, for example, a plastic.
• Thefemoral component992 and thestem component912 may be made of any suitable material, for example, a plastic, a composite, or a metal and if made of a metal, for example, cobalt chromium alloy, stainless steel alloy, or titanium alloy.
• Referring now toFIG. 18, yet another embodiment of the present invention is shown asshoulder prosthesis1000. Theshoulder prosthesis1000 includes astem1010 and a glenoid1094. Thestem1010 includes astem component1012 for cooperation withhumerus9.
• Thestem component1012 includes a distal stem portion1014 and aproximal body portion1016. Theproximal body portion1016 includes asleeve1026 defining apocket1032 therein. Within the pocket1032 astem planer face1036 is formed. Extending distally from thestem planer face1036 is a taperedaperture1048. Extending distally from the taperedaperture1048 is acylindrical aperture1052 havinginternal threads1056 formed thereon.
• Thestem1010 further includes aneck component1018 having adistal body portion1022 and aproximal neck portion1020. Thedistal body portion1022 defines anaperture1050 therein.
• Thedistal body portion1022 defines a distalbody planer face1040 as well as aperiphery1078. Theperiphery1078 and theneck planer face1040 cooperate withpocket1032 to position theneck component1018 with thestem component1012. Theneck component1018 further includes aprotrusion1046 extending from theplaner face1040. Theprotrusion1046 matingly fits with theaperture1048 to provide a taper-lock of theneck component1018 to thestem component1012.
• While theneck component1018 may be securely fastened to thestem component1012 by means of the protrusion in taper lock, it should be appreciated that theshoulder prosthesis1000 may further include a connector in the form of ascrew1044. Thescrew1044 fits within theaperture1050 of theneck component1018 and includesexternal threads1049 that cooperate with theinternal threads1056 formed on thestem component1012.
• Theproximal neck portion1020 includes anexternal taper1062. Theexternal taper1062 is adapted to receivehead1060. Thehead1060 cooperates with glenoid1094 secured to glenoid facia3 by pigs1086.Stem1010,head1060, and glenoid1094 may be made of any suitable durable material. Thestem1010 including thestem component1012 and theneck component1018 as well as thescrew1044 may be made, for example, of a plastic, a metal, or a composite. If made of a metal, theneck component1018,stem component1012, andscrew1044 may be made of, for example, a cobalt chromium alloy, a stainless steel alloy, or a titanium alloy. The glenoid1094 may be made of a metal or be made of, for example, a more pliable material, for example, a plastic.
• Referring now toFIG. 19, yet another embodiment of the present invention is shown askit1100. Thekit1100 includes thetrial hip stem1110 and theimplant hip stem1210. Thetrial hip stem1110 and theimplant hip stem1210 preferably have similar, if not almost identical, shapes and dimensions. Thetrial1110 is implanted into the body and used to perform a trial reduction or to verify the dimensions and selection of the hip stem components. The trial is removed after a trial reduction and the corresponding implant is permanently secured into the bone of the patient. The use of the trial verifies the selection of the implant and if the trial selection is believed to be sub-optimum, an alternate trial is used in the patient and if that alternate trial is found to be optimum, its corresponding implant is then implanted into the patient.
• Trial1110 includes atrial stem component1112 and atrial neck component1118. Thetrial stem component1112 includes adistal stem portion1114 and aproximal body portion1116. Theproximal body portion1116 includes asleeve portion1126 defining apocket1132 and asurface1136. Extending distally from thesurface1136 is acavity1148.
• Thetrial1110 further includes thetrial neck component1118. Thetrial neck component1118 includes adistal body portion1122 and aproximal neck portion1120. Thedistal body portion1122 includes aperiphery1178 for fitting against asleeve portion1126 of thestem component1112. Thedistal body portion1122 further includes asurface1140 for mating with thesurface1136 of thestem component1112. Thedistal body portion1122 also includes aprotrusion1146 which mates withcavity1148 of thestem component1112. Theprotrusion1146 defines included angle ββ.
• The angle ββ is selected to provide for a self-locking taper betweenprotrusion1146 and thecavity1148. The angle ββ may be, for example, from two to twenty degrees (2°-20°).
• The angle ββ is preferably selected by the formula:
  Tan ββ/2<μ
  where: β=coefficient of friction
• • ββ=included angle
• Theproximal neck portion1120 includes anexternal taper1162 to whichhead1160 is matingly fitted.
• Theimplant hip stem1210 has a size and shape the same astrial1110. For example, theimplant1210 includes astem component1212 having adistal stem1212portion1214 and aproximal body portion1216. Theproximal body portion1216 includes asleeve portion1226 definingpocket1232. Thepocket1232 includes asurface1236 as well as acavity1248 extending below thesurface1236.
• Theimplant hip stem1210 also includes aneck component1218 including adistal body portion1222 and aproximal neck portion1220. Thedistal body portion1222 defines aperiphery1278 thereof, as well as asurface1240 of thedistal body portion1222. Aprotrusion1246 extends downwardly from thesurface1240 and defines an included angle ββ. Theproximal neck portion1220 includes anexternal taper1262 to whichhead1260 is matingly fitted.
• Thetrial stem component1112 may be first implanted into the patient and thetrial neck component1118 may be secured to thetrial stem component1112. Alternatively, theimplant stem component1212 may be permanently secured to the patient and thetrial neck component1118 may be fitted to theimplant stem component1212.
• Thetrial neck component1118 may be secured to theimplant stem component1212 and a trial reduction made. If the trial reduction is satisfactory, theimplant neck component1218, which is identical to thetrial neck component1118, may be implanted into the patient. If, however, thetrial neck component1118 is found in a trial reduction to not be optimum, an alternate trial neck component may be utilized in a trial reduction attempted with the new trial neck component. If that second trial neck component is found to be satisfactory, a corresponding implant neck component is then implanted.
• According to the present invention and referring again toFIG. 19, akit1101 for use in performing joint arthroplasty is shown. Thekit1101 includes the orthopaedic stem trial ortrial hip stem1110 for use in performing joint arthroplasty. Thetrial1110 may be fitted to acavity2 in thecanal4 of along bone6 and assists in performing a trial reduction in performing joint arthroplasty. Theorthopaedic stem trial1110 includes canal component ortrial stem component1112 having an external periphery1113. A portion of thecanal component1112 may be fitted to thecavity2 in thecanal4 of thelong bone6. Thecanal component1112 includes distal stem portion orcanal portion1114 that has afirst end1115 for insertion into thecavity2 and an opposedsecond end1117. Thecanal component1112 further includes asleeve portion1126 extending from thesecond end1117 of thecanal portion1114. Thesleeve portion1126 has aninternal periphery1119 that defines pocket orinternal cavity1132. Thesleeve portion1126 also has anexternal periphery1121.
• Theorthopaedic stem trial1112 also includes trial neck component orjoint component1118 removably connectable to thecanal component1112. Thejoint component1118 has neck portion orbody portion1120 and distal body portion orconnection portion1122. Theconnection portion1122 of thejoint component1118 defines anexternal periphery1178. A portion of theexternal periphery1121 of thesleeve portion1126 may be fitted to thecavity2 of thelong bone6. At least a portion of theexternal periphery1178 of theconnection portion1122 of thejoint component1118 may be fitted into theinternal cavity1132 of thesleeve portion1126 so that theexternal periphery1178 of theconnection portion1122 of thejoint component1118 is spaced inwardly from theexternal periphery1121 of thesleeve portion1126 of thestem component1112 when thejoint component1118 is fixedly connected to thestem component1112 so that thejoint component1118 may be removed from thelong bone6.
• Thekit1101 includes orthopaedic hip stem ororthopaedic stem implant1210 for use in performing joint arthroplasty. Theimplant1210 may be fitted tocavity2 incanal4 oflong bone6 to perform a joint arthroplasty. Theorthopaedic stem implant1210 includes implant stem component orcanal component1212 having anexternal periphery1221. At least a portion of thecanal component1212 may be fitted to thecavity2 in thecanal4 of thelong bone6. Thecanal component1212 includes distal stem portion orcanal portion1214 having afirst end1215 for insertion into thecavity2 and an opposedsecond end1217. Thecanal component1212 further includessleeve portion1226 extending from thesecond end1217 of thecanal portion1214. Thesleeve portion1226 has aninternal periphery1219 that defines pocket orinternal cavity1232. Thesleeve portion1226 also has anexternal periphery1221. Theorthopaedic stem implant1210 also includes implant neck component orjoint component1218 that may be removably connected to thecanal component1212. Thejoint component1218 has distal body portion orconnection portion1222 and neck portion orbody portion1220. Theconnection portion1222 of thejoint component1218 definesexternal periphery1278. A portion ofexternal periphery1221 of thesleeve portion1226 may be fitted to thecavity2 of thelong bone6. A portion of theexternal periphery1278 of theconnection portion1222 of thejoint component1218 may be fitted into theinternal cavity1232 of thesleeve portion1226. Theexternal periphery1278 of theconnection portion1222 of thejoint component1218 is spaced thereby inwardly from theexternal periphery1221 of thesleeve portion1226 of thestem component1212. This is accomplished when thejoint component1218 is fixedly connected to the stem component121. Thejoint component1218 may thereby be removed from the long bone without disturbing the fixation of thestem component1212 to thelong bone6.
• Referring now toFIG. 20, yet another embodiment of the present invention is shown asmethod1300 for treating orthopedic joint disease of the patient. Themethod1300 includes afirst step1310 of implanting an orthopedic implant into a cavity in the canal of the long bone. The orthopedic implant includes a stem component and a first joint component fixedly connectable to the joint component. The joint component is adapted for removal from the long bone without disturbing the fixation of the stem component to the bone. Themethod1300 includes asecond step1312 of monitoring the condition of the patient and athird step1314 of determining that the patient needs a revision prosthesis. Themethod1300 also includes afourth step1316 of providing a second joint component compatible with the stem component. Themethod1300 further includes afifth step1318 of removing the first joint component from the stem component of the orthopedic implant in vivo without disturbing the fixation of the stem component to the bone the orthopedic implant. Themethod1300 further includes asixth step1320 of implanting the second joint component into the stem component in vivo in the patient.
• According to the present invention and referring now toFIG. 21, yet another embodiment of the present invention is shown assurgical method1400. Themethod1400 represents a method for providing revision joint arthroplasty on a patient having an orthopedic implant. The orthopedic implant includes a stem component and a first joint component fixedly connectable to the stem component. The joint component is adapted for removal from the long bone without disturbing the fixation of the stem component to the bone. Themethod1400 includes afirst step1410 of monitoring the condition of the patient and asecond step1412 of determining whether the patient needs a revision prosthesis. Themethod1400 includes athird step1414 of providing a second joint component compatible with the stem component. Themethod1400 further includes afourth step1416 of removing the first joint component from the stem component of the orthopedic implant in vivo in the patient without disturbing the fixation of the stem component to the bone. Themethod1400 further includes afifth step1418 of implanting the second joint component in vivo in the patient.
• Referring now toFIG. 22, another aspect of the present invention is shown asmethod1500 for treating orthopaedic joint disease of a patient. Themethod1500 includes afirst step1510 of resecting a long bone along a resection plane and asecond step1512 preparing a cavity in the canal of the long bone. The method also includes athird step1514 of implanting an orthopaedic implant into a cavity in the canal of the long bone. The orthopaedic implant includes a joint component having a canal element and a first body element. The first body element may be fixedly connected to the canal element. The orthopaedic implant is secured in the canal of the long bone with the first body element being spaced from the long bone. The method further includes afourth step1516 of monitoring the condition of the patient and afifth step1518 of determining that the patient needs a revision prosthesis. The method also includes asixth step1520 of providing a second body element connectable to the canal element and aseventh step1522 of removing the first body element from the canal element of the orthopaedic implant in vivo in the patient without disturbing the fixation of bone surrounding the canal element of the orthopaedic implant and without damaging bone surrounding the first body element. The method further includes aneighth step1524 of implanting the second body element into the canal element in vivo in the patient.
• Referring now toFIG. 23 amethod1600 for providing joint arthroplasty on a joint of a patient with an orthopaedic implant is shown. Themethod1600 includes afirst step1610 of resecting a long bone along a resection plane and asecond step1612 of preparing a cavity in the canal of the long bone. The method also includes athird step1614 of implanting an orthopaedic implant canal component into a cavity in the canal of a long bone. The orthopaedic implant canal component may have a stem element and a first body element fixedly connectable to the stem element. The orthopaedic implant canal component is secured in the canal of the long bone. The method further includes afourth step1616 of connecting an orthopaedic trial body component to the implant canal component, the orthopaedic trial body component being spaced from the long bone and afifth step1618 of performing a trial reduction of the joint of the patient. The method also includes asixth step1620 of determining if the orthopaedic trial body component provides satisfactory results for the patient and aseventh step1622 of implanting an orthopaedic implant body component corresponding to the orthopaedic trial body component onto the orthopaedic implant canal component if the orthopaedic trial body component provides satisfactory results for the patient.
• Thethird step1614 of implanting the canal component step may further include permanently securing the canal component to the long bone.
• Thethird step1614 of implanting the canal component step may further include positioning the canal component such that the canal component intersects the resection plane.
• Referring now toFIG. 24 the present invention may be in the form of akit1700 for use in performing joint arthroplasty. Thekit1700 includes acanal component implant1712I having an external periphery1713I. A portion of thecanal component implant1712I may be fitted to acavity2 in acanal4 of along bone6. Thecanal component implant1712I includes acanal portion1714I. Thecanal portion1714I has a first end1715I for insertion into thecavity2 and an opposedsecond end1717I.
• Thecanal component implant1712I further including a sleeve portion1726I extending from thesecond end1717I of thecanal portion1714I. The sleeve portion1726I has aninternal periphery1719I defining an internal cavity1732I. The sleeve portion1726I also has an external periphery1721I. Thekit1700 also includes a first joint component implant removeably connectable to the canal component implant. The firstjoint component implant1718I has a body portion1720I and a connection portion1722I. The connection portion1722I of the firstjoint component implant1718I has an external periphery1778I. A portion of the external periphery1778I of the connection portion1722I of the firstjoint component implant1718I may be fitted into the internal cavity1732I of the sleeve portion1726I of thecanal component implant1712I, so that the external periphery1778I of the connection portion1722I of the firstjoint component implant1718I is spaced inwardly from the external periphery1721I of the sleeve portion1726I of thecanal component implant1712I when the firstjoint component implant1718I is fixedly connected to thecanal component implant1712I so that the firstjoint component implant1718I may be removed from thelong bone6 without disturbing the fixation of thecanal component implant1712I to thelong bone6.
• Thekit1700 also includes a firstjoint component trial1718T generally corresponding in size and shape with the firstjoint component implant1718I. The firstjoint component trial1718T may be removeably connected to thecanal component implant1712I. The firstjoint component trial1718T having a body portion1720T and a connection portion1722T. The connection portion1722T of the firstjoint component trial1718T has an external periphery1778T. A portion of the external periphery1778T of the connection portion1722T of the firstjoint component trial1718T may be fitted into the internal cavity1732I of the sleeve portion1726I of thecanal component implant1712I. The external periphery1778T of the connection portion1722T of the firstjoint component trial1718T is thereby spaced inwardly from the external periphery1721T of the sleeve portion1726T of thecanal component implant1712I. This occurs when the firstjoint component trial1718T is fixedly connected to thecanal component implant1712I. The firstjoint component trial1718T may thus be removed from thelong bone6 without disturbing the fixation of thecanal component implant1712I to thelong bone6.
• The kit further includes a secondjoint component implant1818I removeably connectable to thecanal component implant1712I. The secondjoint component implant1818I has a body portion1820I and a connection portion1822I. The connection portion1822I of the secondjoint component implant1818I has an external periphery1878I. A portion of the external periphery1878I of the connection portion18221 of the secondjoint component implant1818I may be fitted into the internal cavity1732I of the sleeve portion1726I of thecanal component implant1712I so that the external periphery1878I of the connection portion1822I of the secondjoint component implant1818I is spaced inwardly from the external periphery1721I of the sleeve portion1726I of thecanal component implant1712I when the secondjoint component implant1818I is fixedly connected to thecanal component implant1712I so that the secondjoint component implant1818I may be removed from thelong bone6 without disturbing the fixation of thecanal component implant1712I to thelong bone6.
• Thekit1700 also includes a secondjoint component trial1818T generally corresponding in size and shape with the secondjoint component implant1818I. The secondjoint component trial1818T may be removeably connectable to thecanal component implant1712I. The secondjoint component trial1818T having a body portion1820T and a connection portion1822T. The connection portion1822T of the secondjoint component trial1818T has an external periphery1878T. A portion of the external periphery1878T of the connection portion1822T of the secondjoint component trial1818T may be fitted into the internal cavity1732I of the sleeve portion1726I of thecanal component implant1712I so that the external periphery1878T of the connection portion1822T of the secondjoint component trial1818T is spaced inwardly from the external periphery1721I of the sleeve portion1726I of thecanal component implant1712I when the secondjoint component trial1818T is fixedly connected to thecanal component implant1712I so that the secondjoint component trial1818T may be removed from thelong bone6 without disturbing the fixation of thecanal component implant1712I to thelong bone6.
• Thekit1700 permits thecanal component implant1712I to be permanently implanted. Thekit1700 also permits the firstjoint component trial1718T to be assembled to thecanal component implant1712I and used to perform a trial reduction. Thekit1700 further permits the firstjoint component trial1718T to be replaced with the secondjoint component trial1818T if the trial reduction has unsatisfactory results.
• Referring now toFIG. 25, anorthopaedic implant2011 is used to perform joint arthroplasty. A portion of theorthopaedic implant2011 is capable of being fitted tocavity2 in thecanal4 oflong bone6. Thecavity2 extends from a resectedplane11 of thelong bone6. Theorthopaedic implant2011 includesjoint component2010. Thejoint component2010 includesstem element2012 definingexternal periphery2058 of thestem element2012. Thestem element2012 has afirst end2015 for insertion into thecavity2. Theexternal periphery2058 of thestem element2012 has astem resection ring2041. Thestem resection ring2041 may be aligned with the resectedplane11 of thelong bone6.
• Thejoint component2010 also includes afirst body element2018 capable of being fixedly fitted to thestem element2012. Thefirst body element2018 includes anexternal periphery2078. Theexternal periphery2078 of thefirst body element2018 has abody component ring2043. Thebody component ring2043 may be aligned with the resectedplane11 of thelong bone6. Acanal portion2045 of thefirst body element2018 extends generally from thecomponent ring2043 of theexternal periphery2078 of thefirst body element2018 toward thefirst end2015 of thestem element2012 when thefirst body element2018 is fixedly connected to thestem element2012.
• Theexternal periphery2047 of thecanal portion2045 of thefirst body element2018 is spaced inwardly fromexternal periphery2058 of thestem element2012 when thefirst body element2018 is fixedly connected to thestem element2012 so that thefirst body element2018 may be removed from thelong bone6 without disturbing the fixation of thestem element2012 to thelong bone6.
• As shown inFIG. 25 theorthopaedic implant2011 may be configured such that the first mentionedbody element2018 may be removably fixedly connected to thestem element2012 and may include asecond body element2018S that may be removably fixedly connected to thestem element2012. Thefirst body element2018 and thesecond body element2018S may thus be interchangeably connected to thestem element2012 while thestem element2012 is implanted in thecavity2 of thelong bone6.
• Theorthopaedic implant2011 may have a portion of thestem element2012 that extends over a portion of thefirst body element2018.
• Thestem element2012 of the orthopaedic implant, as shown inFIG. 25, may include asleeve portion2016. Thesleeve portion2016 may receive at least a portion of thecanal portion2045 of thefirst body element2018.
• Thefirst body element2018 of theorthopaedic implant2011, as shown inFIG. 25, may be removably securable to thestem element2012.
• As shown inFIG. 25, aportion2036 of theexternal periphery2058 of thestem element2012 may be generally planar. Also aportion2040 of the external periphery of thebody element2018 may be generally planar. Theportion2036 of theexternal periphery2058 of thestem element2012 and theportion2040 of theexternal periphery2078 of thebody element2018 may be in contact with each other.
• Aconnector2044 may be used to connect thebody element2018 to thestem element2012. Theconnector2044 may be in the form of a screw or a pin (seeFIG. 16).
• Thebody element2018 may include aprotrusion2044 extending from a surface of the connection element2022. Thestem element2012 may include an aperture2048 for receiving theprotrusion2046. It should be appreciated that the body may include an aperture (not shown) and the stem element may include a protrusion (not shown). The protrusion may be tapered.
• Theimplant2011 may further include secondjoint component2010S for cooperation with a firstjoint component2010. A portion of the external periphery of thebody element2018 may include anarticulation surface2017 for articulation with the secondjoint component2010S.
• The secondjoint component2010S may be adapted for fixed implantation onto asecond bone17. Abearing component2055 may be positioned between the firstjoint component2010 and the secondjoint component2010S. Thebearing component2055 articulates at the firstjoint component2010 and is fixedly attached to the secondjoint component2010S. Alternately thebearing component2055 may articulate with the secondjoint component2010S and be fixedly attached to the firstjoint component2010.
• As shown inFIG. 25, theorthopaedic implant2011 may be in the form of a hip implant. Thejoint component2010 is in the form of a hip stem. Theorthopaedic implant2011 may also include the secondjoint component2010S in the form of an acetabular cup for articulating cooperation with the hip stem.
• As shown inFIG. 25, thebody element2018 may include atapered protrusion2059. Theorthopaedic implant2011 may also include a generallyspherical head2060. Thehead2060 may, as shown, be removably fixedly secured to the taperedprotrusion2059.
• As shown inFIG. 1, the joint component defines alongitudinal axis2039. Thestem element2012 may have asleeve portion2026. Thesleeve portion2026 may define a wall thickness WT3 of thesleeve portion2026. The wall thickness WT3 may generally be uniform about theouter periphery2058 of thestem element2012 in a plane normal to thelongitudinal axis2039 of thejoint component2010 and may be defined by wall thickness WT3. Theexternal periphery2078 of thebody element2018 may, as shown, closely conform to thesleeve portion2026 of thestem element2012.
• It should be appreciated that theorthopaedic implant2011 may be in the form of a knee prosthesis, a hip prosthesis or a shoulder prosthesis.
• Referring again toFIG. 25, it should be appreciated that thestem element2012 may be interchangeably connectable to the firstjoint element2018 and with the secondjoint element2018S. The firstjoint element2018 and the secondjoint element2018S may as shown include a different dimension, or several different dimensions from each other. Thus, it should be appreciated that the stem element can receive joint elements of varying heights, offsets and degrees of version.
• Continuing to refer toFIG. 25, thestem resection ring2041 may be in the form of a recess. Therecess2041 may be a score mark or a machined or formed groove. It should be appreciated that the ring may likewise be a raised area or protrusion (not shown). It should be further appreciated that thering2041 may be acid etched or marked with ink or paint. It should be appreciated that thering2041 may be continuous or discontinuous around thestem2012.
• It should be appreciated thatbody element2018 may likewise includebody component ring2043. Thebody component ring2043 may have the same configuration as that of thestem resection ring2041 and may be recessed or protruding.
• It should be appreciated that thestem resection ring2041 and/or thebody component ring2043 may, as shown inFIG. 25, be visually distinguishable from theexternal periphery2058 of thestem element2012 and/or theexternal periphery2078 of thebody element2018.
• It should likewise be appreciated that thestem resection ring2041 and/or thebody component ring2043 may be visually indistinguishable from theexternal periphery2058 of thestem element2012 and/or theexternal periphery2078 of thebody element2018. Thestem resection ring2041 and/or thebody component ring2043 may thus be invisible.
• According to the present invention and referring toFIG. 26, a firstjoint component2118 for use with astem component2112 having acanal portion2114 and a sleeve portion2116 for use as part of aprothesis2101 in performing joint arthroplasty is shown. The sleeve portion2116 of thestem component2112 has aninternal periphery2134 and anexternal periphery2158. A portion of theexternal periphery2158 of the sleeve portion2116 of thestem component2112 may be fitted to acavity2 in thecanal4 of along bone6. Thecavity2 extends from a resectedplane11 of thelong bone6.
• The firstjoint component2118 includes abody portion2122 and aconnection portion2120. Theconnection portion2120 extends from thebody portion2122 and has anexternal periphery2128. Theexternal periphery2128 of theconnection portion2120 may be positioned within theinternal periphery2134 of the sleeve portion2116 of thestem component2112.
• Theexternal periphery2128 of theconnection portion2120 may include aconnection resection ring2139. Theconnection resection ring2139 may be used for alignment with the resectedplane11 of thelong bone6. Theexternal periphery2128 of theconnection portion2120 is spaced inwardly from theexternal periphery2158 of the sleeve portion2116 of thestem component2112 when the firstjoint component2118 is fixedly connected to thestem component2112 so that thejoint component2018 may be removed from thelong bone6 without disturbing the fixation of thestem component2112 to thelong bone6.
• As shown inFIG. 26, theconnection portion2120 of the firstjoint component2118 may be adapted to be removably fixedly connected to thestem component2112. Further theprosthesis2101 may include a secondjoint component2160 removably fixedly connectable to the stem component. The firstjoint component2118 and the secondjoint component2160 may, as shown, be interchangeably connected to thestem component2112 while thestem component2112 is implanted in thecavity2 of thelong bone6.
• As shown inFIG. 26, theconnection portion2120 of the firstjoint component2118 may be adapted to fit within theinternal periphery2134 of thestem component2112.
• As shown inFIG. 26, aportion2136 of theexternal periphery2158 of thestem component2112 may be generally planar. Further aportion2140 of theexternal periphery2128 of the firstjoint component2118 may be generally planar. Theportion2136 of theexternal periphery2158 of thestem component2112 and theportion2140 of theexternal periphery2128 of the firstjoint component2118 may, as shown, be adapted for contact with each other.
• The firstjoint component2118, as shown inFIG. 26, may include afeature2148 for cooperation with aconnector2144 to connect the firstjoint component2118 to thestem component2112. Thefeature2148 may be in the form of anaperture2148 for passing theconnector2144 through the firstjoint component2118. For example, theaperture2148 may be a cylindrical aperture.
• The firstjoint component2118 as shown inFIG. 26 may include aprotrusion2146. Alternatively, the joint component may include an aperture (not shown). Theprotrusion2146 may, as shown, be tapered.
• It should be appreciated that firstjoint component2118 may be in the form of ahip stem neck2118.
• The firstjoint component2118 and the secondjoint component2160 may, as shown inFIG. 26, be interchangeably connectable to thestem component2112. Thereby thestem component2112 can receive joint components of varying heights, offsets and degrees of version.
• According to the present invention and as shown inFIG. 27, astem component2212 for use with ajoint component2218 having abody portion2220 and aconnection portion2222 in performing joint arthroplasty is provided. Theconnection portion2222 of thejoint component2218 has anexternal periphery2278. At least a portion of thestem component2212 may be fitted tocavity2 incanal4 of along bone6. Thestem component2212 includes a canal portion2214 having afirst end2215 for insertion into the cavity and an opposedsecond end2217.
• Thestem component2212 also includes asleeve portion2226 extending from thesecond end2217 of the canal portion2214. Thesleeve portion2226 has an internal periphery2219 that forms aninternal cavity2232. Thesleeve portion2226 has anexternal periphery2221. The canal portion2214 and/or thesleeve portion2226 may be in removable fixed engagement with thejoint component2218. At least a portion of theexternal periphery2221 of thesleeve portion2226 may be fitted to thecavity2 of thelong bone6. At least a portion of theexternal periphery2278 of theconnection portion2222 of thejoint component2218 may be fitted into theinternal cavity2232 of thesleeve portion2226, so that theexternal periphery2278 of theconnection portion2222 of thejoint component2218 is spaced inwardly from theexternal periphery2221 of thesleeve portion2226 of thestem component2212 when thejoint component2218 is fixedly connected to thestem component2212 so that thejoint component2218 may be removed from thelong bone6 without disturbing the fixation of thestem component2212 to thelong bone6.
• As shown inFIG. 27, thestem component2212 may be configured with a portion2236 of theexternal periphery2221 of thestem component2212 being generally planar. Further aportion2240 of theexternal periphery2278 of thejoint component2218 may as shown be generally planar. The portion2236 of theexternal periphery2221 of thestem component2212 and theportion2240 of theexternal periphery2278 of thejoint component2218 as shown inFIG. 27 it should be appreciated are adapted for contact with each other.
• Thestem component2212 may as shown inFIG. 27 include afeature2252 for cooperation with aconnector2244 to connect thestem component2212 to thejoint component2218. As shown inFIG. 27, thefeature2252 may be in the form of a threaded cavity or in the form of a cylindrical cavity which have been formed in thestem component2212.
• Further and as shown inFIG. 27, thestem component2212 may include aconnection feature2248 for connection with thejoint component2218. Theconnection feature2248 may, as shown, be in the form of acavity2248 formed in thestem component2212. Alternatively, the connection feature (not shown) may be in the form of a cavity. Theconnection feature2248 may be tapered.
• Thestem component2212 may be in the form of ahip stem2212. Alternatively thestem component2212 may be in the form of a tibial implant or a shoulder stemFIGS. 17 and 18 respectively. It should be appreciated that thestem component2212 may be any component for cooperation with along bone6.
• Thesleeve portion2226 of thestem component2212 may define a wall thickness WT thereof. The wall thickness WT may, as shown, be generally uniform about theexternal periphery2221 of thesleeve portion2226 in a plane normal tolongitudinal axis2223 of thejoint component2218. Theexternal periphery2278 of theconnection portion2222 of thejoint component2218 may, as shown, be adapted to closely conform to thesleeve portion2226 of thestem component2212.
• It should be appreciated that thestem component2212 may be interchangeably connected to a variety ofjoint components2218 with similar or identical connectors, so that thestem component2212 can receive joint components of varying heights, offsets and degrees of version.
• Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims (22)

1. An orthopaedic implant for use in performing joint arthroplasty, a portion of said orthopaedic implant to be fittable to a cavity in the canal of a long bone, the cavity extending from a resected plane of the long bone, said orthopaedic implant including a joint component comprising

a stem element defining an external periphery thereof, said stem element defining a first end thereof for insertion into the cavity, the external periphery of said stem element defining a stem resection ring thereof, the stem resection ring adapted for alignment with the resected plane of the long bone, and

a body element fixedly connectable to said stem element, said body element defining an external periphery thereof, the external periphery of said body element defining a body resection ring thereof, the body resection ring adapted for alignment with the resected plane of the long bone, a canal portion of said body element extending generally from the resection ring of the external periphery of said body element toward the first end of said stem element when said body element is fixedly connected to said stem element, the external periphery of the canal portion of said body element spaced inwardly from the external periphery of said stem element when said body element is fixedly connected to said stem so that said body element may be removed from the long bone without disturbing the fixation of the stem element to the long bone.

2. The orthopaedic implant ofclaim 1:

wherein said first mentioned body element is removably fixedly connectable to said stem element; and

further comprising a second body element removably fixedly connectable to said stem element, whereby said first body element and said second body element are interchangeably connected to said stem component while said stem element is implanted in the cavity of the long bone.

3. The orthopaedic implant ofclaim 1, wherein a portion of said stem element extends over a portion of said body element.

4. The orthopaedic implant ofclaim 1, wherein said stem element comprises a sleeve portion, said sleeve portion adapted for receiving at least a portion of the canal portion of said body element.

5. The orthopaedic implant ofclaim 1, wherein said body element is removably securable to said stem element.

6. The orthopaedic implant ofclaim 1:

wherein a portion of the external periphery of said stem element is generally planar; and

wherein a portion of the external periphery of said body element is generally planar, wherein a portion of the external periphery of said canal component is generally planar, the portion of the external periphery of said stem element and the portion of the external periphery of said body element being in contact with each other.

7. The orthopaedic implant ofclaim 1, further comprising a connector to connect said body element to said stem element.

8. The orthopaedic implant ofclaim 7, wherein said connector comprises a screw.

9. The orthopaedic implant ofclaim 7, wherein said connector comprises a pin.

10. The orthopaedic implant ofclaim 1:

wherein one of said stem element and said body element comprises a protrusion extending therefrom; and

wherein the other of said stem element and said body element defines an aperture for receiving the protrusion.

11. The orthopaedic implant ofclaim 10, wherein the protrusion is tapered.

12. The orthopaedic implant ofclaim 1:

further comprising a second joint component for cooperation with said first mentioned joint component; and

wherein at least a portion of the external periphery of said body element comprises an articulation surface for articulation with said second joint component.

13. The orthopaedic implant ofclaim 1:

further comprising a second joint component for fixed implantation onto a second bone; and

a bearing component positionable between said first mentioned joint component and said second joint component, said bearing component adapted for articulation with at least one of said first mentioned joint component and said second joint component.

14. The orthopaedic implant ofclaim 1:

wherein said orthopaedic implant comprises a hip implant;

wherein said joint component comprises a hip stem; and

further comprising an acetabular cup for articulating cooperation with said hip stem.

15. The orthopaedic implant ofclaim 14:

wherein said body element defines a tapered protrusion extending from said body element; and

further comprising a generally spherical head removably fixedly securable to said tapered protrusion.

16. The orthopaedic implant ofclaim 1:

wherein said joint component defines a longitudinal axis thereof; and

wherein said stem element defines a sleeve portion thereof, the sleeve portion defining a wall thickness thereof, the wall thickness being generally uniform about the outer periphery of said stem element in a plane normal to the longitudinal axis of said joint component, the external periphery of said body portion adapted to closely conform to the sleeve portion of said stem element.

17. The orthopaedic implant ofclaim 1, wherein said orthopaedic implant comprises one of a knee prosthesis, a hip prosthesis or a shoulder prosthesis.

18. The orthopaedic implant ofclaim 1:

wherein said orthopaedic implant comprises a shoulder implant;

wherein said first joint component comprises a humeral stem; and

further comprising a glenoid component for articulating cooperation with said humeral stem.

19. The stem component ofclaim 1, wherein said stem element is interchangeably connectable to the joint element, so that the said stem element can receive joint element of varying heights, offsets and degrees of version.

20. The stem component ofclaim 1, wherein at least one of the stem resection ring and the body resection ring is visually distinguishable from the external periphery of said one of the stem resection ring and the body resection ring.

21. An orthopaedic implant stem for use in performing joint arthroplasty, a portion of said orthopaedic implant stem to be fitted to a cavity in the canal of a long bone, said orthopaedic implant stem comprising:

a canal element defining an external periphery thereof, said canal element defining a first end thereof for insertion into the cavity and an opposed connection end, said canal element defining a recess therein extending from the opposed connection end of said canal element, the recess having a internal periphery thereof, the canal element further defining an external periphery thereof spaced outwardly from the internal periphery of the recess; and

a body element fixedly connectable to said canal element, a first portion of said body element adapted for insertion into the recess of said canal element when said first element is fixedly connected to said canal element, the first portion of said body element spaced inwardly from the external periphery of said canal element when said body element is fixedly connected to said canal element so that said body element may be removed from the long bone without disturbing the fixation of said canal element to the long bone.

22. A method for treating orthopaedic joint disease of a patient, comprising the steps of:

resecting a long bone along a resection plane;

preparing a cavity in the canal of the long bone;

implanting an orthopaedic implant into a cavity in the canal of the long bone, the orthopaedic implant including a joint component having a canal element and a first body element fixedly connectable to the canal element, the orthopaedic implant being secured in the canal of the long bone with the first body element being spaced from the long bone;

monitoring the condition of the patient;

determining that the patient needs a revision prosthesis;

providing a second body element connectable to the canal element;

removing the first body element from the canal element of the orthopaedic implant in vivo in the patient without disturbing the fixation of bone surrounding the canal element of the orthopaedic implant and without damaging bone surrounding the first body element; and

implanting the second body element into the canal element in vivo in the patient.

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