US20080255664A1 - Percutaneously deliverable orthopedic joint device - Google Patents

Abstract

A percutaneously implantable orthopedic device is a shape-changing joint prosthesis with a generally arcuate or generally rectilinear configuration which is delivered through a delivery device in a substantially straightened or slightly curved configuration into a joint in a patient. The generally arcuate configuration may include an open ring or spiral shape. The generally rectilinear configuration may include a polygon or zig-zag shape. The delivery and retrieval device can be a syringe, hypodermic needle or cannula. The orthopedic device is moveable into its generally arcuate or generally rectilinear configuration in the joint by manipulation or a shape memory set. The orthopedic device acts as a soft compliant bearing surface or cushion that minimizes the bone-on-bone wear from articulation and loading.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application claims the benefit of priority from U.S. Provisional No. 60/911,056 filed Apr. 10, 2007, which is incorporated in its entirety by reference, herein.
BACKGROUND OF THE INVENTION
• 1. Field of Invention
• Various embodiments of the present inventions relate to the treatment of osteoarthritis, rheumatoid arthritis, and any other joint degenerative process with a minimally invasive implantable device to reduce, amongst other things, bone-to-bone contact at a joint.
• 2. Related Art
• Today there are an increasing number of patients with osteoarthritis, rheumatoid arthritis, and other joint degenerative processes. Osteoarthritis is by far the most common type of arthritis, and the percentage of people who have it grows higher with age. An estimated 12.1 percent of the U.S. population (nearly 21 million Americans) age 25 and older have osteoarthritis of one form or another. Although more common in older people it usually is the result of a joint injury, a joint malformation, or a genetic defect in joint cartilage. Its time of occurrence differs: osteoarthritis tends to start for men before the age of 45, and after the age of 45 it is more common in women. It is also more likely to occur in people who are obese or overweight and is related to those jobs that stress particular joints.
• It affects the musculoskeletal system and specifically the joints—where two or more bones meet. It most often occurs in the hands (particularly at the ends of the fingers and thumbs), spine (particularly at the neck and lower back), knees, and hips. Joint problems can include; stiffness, inflammation and damage to joint cartilage (the tough, smooth tissue that covers the ends of the bones, enabling them to glide against one another) and surrounding structures. Such damage can lead to joint weakness, instability and visible deformities that, depending on the location of joint involvement, can interfere with the most basic daily tasks such as walking, climbing stairs, using a computer keyboard, cutting your food or brushing your teeth. This ultimately results in moderate to severe pain and joint deterioration. As this is a degenerative process of the joint it can ultimately end in total joint replacement. Drug regimes can provide temporary relief from the pain but do not slow down the crippling affects. The extreme result or end point in traditional treatments is an open surgery procedure for placing a spacer or total joint replacement with a prosthetic device. It would be desirable as well as beneficial if there were an intermediary step or alternative treatment before this extreme.
• Current joint replacement therapies (spacers or a total prosthesis) require the joint capsule to be surgically opened and the bone surfaces to be partially or totally removed. Various spacers and or prosthetic devices can be made from a number of biocompatible polymers such as silicone, polyurethane, Teflon etc. Both modalities present drawbacks. For example, U.S. Pat. No. 6,007,580 to Matti Lehto et al. describes an implantable spacer that must be fixed at one or both ends to the bone of either end of the knuckle. It is not provided in a shape memory configuration and must be implanted by opening of the knuckle capsule. It further must be affixed at one or both ends to the corresponding bone faces.
• Various spacers in the art can cause inflammation and the total joint replacement can limit the range of motion, compromise the strength and ultimately the stability of the joint. These surgeries are invasive and require the joint capsule to be surgically opened. The incision itself can result in inflammation and infection. Due to the invasiveness of the procedure and the delicate nature of the joint it can result in joint instability prolonged healing times.
SUMMARY OF THE INVENTION
• It would be desirable to provide intermediary treatment before deciding whether to undergo total joint replacement. Such intermediary treatment preferably comprises providing a cushion or improved spacer made of shape-changing, shape-memory or shape-recovering material placed into the joint to minimize pain and slow the deterioration process. It would further be desirable to provide this cushion or improved articulation device in a minimally-invasive procedure; e.g., through a hypodermic needle, cannula or catheter that can be inserted directly into the joint without the necessity of a surgical cut-down procedure and its associated risks. There would be a distinct benefit to the patient in that there would be a reduction in pain, time, and complexity in conducting the procedure as well as decreasing healing time, reducing post-operative pain, and slowing of deterioration in a joint without the necessity of surgically opening the joint.
• In various embodiments the orthopedic device is an implantable prosthetic that has a substantially non-linear preformed configuration (e.g. a shape that is not a substantially straight line, such as a generally arcuate shape or a generally rectilinear shape composed of more than a single line) which is delivered through a hypodermic needle in a straightened configuration and into the joint. In one embodiment the orthopedic device is an implantable prosthetic generally arcuate open ring or spiral which is delivered through a hypodermic needle in a straightened configuration and into the joint. Then due to its shape memory set, it then assumes an open ring. This ring acts as a compliant bearing surface which minimizes the bone on bone wear from articulation and loading. In another embodiment the orthopedic device is an implantable prosthetic generally rectilinear polygon or series of linear segment shape which is delivered through a hypodermic needle in a straightened configuration and into the joint.
• In one embodiment the orthopedic device is an implantable prosthetic with a series of discrete articulatable elements. The elements, or segments, can be connected by one or more connectors. In one embodiment the orthopedic device is a ratcheted linkage. In another embodiment the orthopedic device is a series of articular layers on a bendable elongate core. In one embodiment the orthopedic device discrete articulatable elements can form a generally arcuate open ring or spiral. In various embodiments the orthopedic device may be delivered through a hypodermic needle in a straightened configuration and into the joint. After delivery, various embodiments of the orthopedic device can resume it generally rectilinear or generally arcuate configuration by being manipulated into that shape or due to a shape memory set. The orthopedic device can act as a compliant bearing surface which minimizes the bone on bone wear from articulation and loading.
• In various embodiments, delivery or retrieval systems include a straight or curved hypodermic needle, syringe, cannula or catheter specially configured to implant or retrieve an orthopedic device with a specific orientation. Certain systems can include specially shaped plungers, needles, interlocks, removable attachments, pinchers, lassos, tethers, hooks, threaded interfaces, reservoirs, or cassette loading systems for interacting with or positioning the orthopedic device. In one embodiment the orthopedic device is an implantable prosthetic generally arcuate open ring or spiral which is delivered through a hypodermic needle in a straightened configuration and into the joint. Then due to its shape memory set, it then assumes an open ring. This ring acts as a compliant bearing surface which minimizes the bone on bone wear from articulation and loading. In another embodiment the orthopedic device is an implantable prosthetic generally rectilinear polygon or series of linear segment shape which is delivered through a hypodermic needle in a straightened configuration and into the joint.
BRIEF DESCRIPTION OF THE DRAWINGS
• These and other features, embodiments, and advantages of the present invention will now be described in connection with preferred embodiments of the invention, in reference to the accompanying drawings. The illustrated embodiments, however, are merely examples and are not intended to limit the invention.
• FIG. 1A is a schematic top view of an orthopedic device according to one embodiment of the present invention comprising a substantially straight configuration.
• FIG. 1B is a schematic top view of an orthopedic device according to one embodiment of the present invention comprising an open hoop arcuate configuration.
• FIG. 1C is a schematic top view of an orthopedic device according to one embodiment of the present invention comprising a nautilus-style spiral arcuate configuration.
• FIG. 2 is a schematic cross-section view perpendicular to a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising an elongate core and an articular layer surrounding at least a portion of the core.
• FIG. 3A is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising a substantially straight configuration, the device comprising an elongate core and an articular layer surrounding at least a portion of the core.
• FIG. 3B is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising an open hoop arcuate configuration, the device comprising an elongate core and an articular layer surrounding at least a portion of the core.
• FIG. 3C is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising a nautilus-style spiral arcuate configuration, the device comprising an elongate core and an articular layer surrounding at least a portion of the core.
• FIG. 3D is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising an open hoop arcuate configuration, the device comprising one or more elongate cores wrapped, braided or folded along a length of the device and an articular layer surrounding at least a portion of the core.
• FIG. 3E is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising a nautilus-style spiral arcuate configuration, the device comprising one or more elongate cores wrapped, braided or folded along a length of the device and an articular layer surrounding at least a portion of the core.
• FIG. 4A is a schematic side view of an elongate core according to one embodiment of the present invention comprising one or more substantially linear or straight members.
• FIG. 4B is a schematic side view of an elongate core according to one embodiment of the present invention comprising one or more wave, curve or zig-zag members disposed in one or more planes.
• FIG. 4C is a schematic side view of an elongate core according to one embodiment of the present invention comprising one or more members in a braided or weave configuration.
• FIG. 5A is a schematic top view of an elongate core according to one embodiment of the present invention comprising an open hoop arcuate configuration and one or more end pieces.
• FIG. 5B is a schematic top view of an elongate core according to one embodiment of the present invention comprising an open hoop arcuate configuration and one or more bends or hooks.
• FIG. 5C is a schematic top view of an elongate core according to one embodiment of the present invention comprising an open hoop arcuate configuration and one or more features bent in or out of the primary plane of the device.
• FIGS. 6A-6K are schematic cross-section views of elongate cores according to various embodiments of the present invention.
• FIG. 7A is a schematic perspective view of an orthopedic device according to one embodiment of the present invention comprising a plurality of independent or interconnectable discrete elongate members.
• FIG. 7B is a schematic perspective view of an orthopedic device according to one embodiment of the present invention comprising a plurality of independent or interconnectable discrete elongate members in a “W” configuration.
• FIG. 8 is a schematic perspective view of an orthopedic device according to one embodiment of the present invention comprising a plurality of independent or interconnectable discrete members.
• FIG. 9A is a schematic side view of an elongate core according to one embodiment of the present invention comprising a plurality of interconnectable discrete members in a substantially straight configuration.
• FIG. 9B is a schematic side view of one interconnectable discrete member ofFIG. 9A.
• FIG. 9C is a schematic side view of an elongate core comprising a plurality of interconnectable discrete members according toFIG. 9A in an arcuate open loop configuration.
• FIG. 10A is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising a handle and a plunger.
• FIG. 10B is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising a substantially straight cannula or needle with a lumen.
• FIG. 10C is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising an arcuate cannula or needle with a lumen.
• FIG. 10D is a schematic side view close up of a distal end of an orthopedic device delivery system according to one embodiment of the present invention comprising a blunted delivery cannula.
• FIG. 10E is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising an angular tip.
• FIG. 11 is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising an implantable orthopedic device, a cannula, and a plunger.
• FIG. 12A is a schematic side cross-sectional view of an orthopedic device delivery system according to one embodiment of the present invention prior to implantation in a joint.
• FIG. 12B is a schematic top cross-sectional view orthogonal toFIG. 12A of two embodiments of orthopedic device delivery systems similar to the system ofFIG. 12A prior to implantation in a joint, wherein on embodiment comprises a substantially straight cannula and the other embodiment comprises an arcuate cannula.
• FIG. 13A is a schematic side cross-sectional view of an orthopedic device delivery system according to the embodiment of the present invention shown inFIG. 12A upon partial insertion of the orthopedic device into the joint.
• FIG. 13B is a schematic top cross-sectional view orthogonal toFIG. 13A of two embodiments of orthopedic device delivery systems according toFIG. 12B upon partial insertion of the orthopedic device into the joint.
• FIG. 14A is a schematic side cross-sectional view of an orthopedic device delivery system according to the embodiment of the present invention shown inFIG. 12A upon deployment of the orthopedic device into the joint.
• FIG. 14B is a schematic top cross-sectional view orthogonal toFIG. 14A of two embodiments of orthopedic device delivery systems according toFIG. 12B upon deployment of the orthopedic device into the joint.
• FIG. 15A is a schematic side cross-sectional view of an orthopedic device delivery system according to the embodiment of the present invention shown inFIG. 12A upon deployment of the orthopedic device into the joint and removal of the delivery cannula.
• FIG. 15B is a schematic top cross-sectional view orthogonal toFIG. 15A of two embodiments of orthopedic device delivery systems according toFIG. 12B upon deployment of the orthopedic device into the joint and removal of the delivery cannula(e).
• FIG. 16A is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a tether and a loop structure in a substantially straight configuration.
• FIG. 16B is a schematic side view of the orthopedic device ofFIG. 16A in an arcuate configuration.
• FIG. 16C is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising one or more tethers in an arcuate configuration.
• FIG. 17 is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a looped arcuate configuration and at least one anchor.
• FIG. 18 is a schematic side view of an orthopedic device removal system according to one embodiment of the present invention comprising an implantable orthopedic device, a cannula, and a snare.
• FIGS. 19A and 19B are schematic perspective and side views of a portion of an interface in an orthopedic device delivery and removal system according to one embodiment of the present invention comprising an implantable orthopedic device and a plunger connectable with a device interface.
• FIGS. 20A-20C are schematic side views of a portion of an interface in an orthopedic device delivery and removal system according to another embodiment of the present invention comprising an implantable orthopedic device and a plunger connectable with a device interface.
• FIG. 21A is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a multiplanar spiral configuration.
• FIG. 21B is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a multiplanar arcuate configuration.
• FIG. 21C is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a “W”-shaped configuration.
• Throughout the figures, the same reference numerals and characters, unless otherwise stated, are used to denote like features, elements, components or portions of the illustrated embodiments. In certain instances, similar names may be used to describe similar components with different reference numerals which have certain common or similar features. Moreover, while the subject invention will now be described in detail with reference to the figures, it is done so in connection with the illustrative embodiments. It is intended that changes and modifications can be made to the described embodiments without departing from the true scope and spirit of the subject invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• As should be understood in view of the following detailed description, this application is primarily directed to apparatuses, systems and methods for minimally-invasive treatment of bone joints. In various embodiments, an orthopedic device suitable for minimally invasive deployment using a tubular delivery apparatus with a lumen or channel, such as a cannula, hypodermic needle, catheter, or another similar apparatus. In various embodiments the orthopedic device is an implantable prosthetic that has a substantially non-linear pre-formed configuration (e.g. a shape that is not a substantially straight line, such as a generally arcuate shape or a generally rectilinear shape composed of more than a single line) which is delivered through a hypodermic needle in a straightened configuration and into the joint. In one preferred embodiment of the invention, an orthopedic device comprises an elongate shape memory body that has a generally arcuate configuration to enhance self-centering positioning of the orthopedic device when deployed. In another embodiment an orthopedic device comprises an elongate shape memory body that has a generally rectilinear configuration to enhance self-centering positioning of the orthopedic device when deployed. In one embodiment an orthopedic device comprises a plurality of elongate shape memory bodies that can be moved into a configuration to enhance self-centering positioning of the orthopedic device when deployed. The body can be manipulated into a substantially straight configuration to permit delivery. In various embodiments, the orthopedic device can be for single or multiple uses, and may be removed from the joint.
1. Implantable Orthopedic Devices
• In various embodiments the orthopedic device can have an arcuate configuration once it is implanted in a joint. As used herein, “arcuate” may refer to curved or rounded configurations or shapes, but can also include generally arcuate configurations and shapes that have some straight aspect or element with curved or rounded configurations or shapes. As used herein, arcuate and generally arcuate shapes can include “C”, “O”, “S”, spiral, nautilus, “Q” and other generally arcuate shapes. Similarly, certain embodiments of the orthopedic device may include rectilinear configurations, which can include polygons such as triangles, squares, rectangles, diamonds, rhombuses, pentagons, hexagons, octagons and other shapes with generally straight edges, and further including shapes and configurations that are generally rectilinear having some curved edge or comers or segments among rectilinear shapes. As used herein, rectilinear and generally rectilinear shapes can include “N”, “M”, “W”, “Z”, “T”, “Y”, “V”, “L”, “X” and other generally rectilinear shapes. Various embodiments of generally arcuate or generally rectilinear shapes can include shapes with both rectilinear and arcuate portions, such as a “P”, “R”, “B”, and “U”.
• In order to deliver certain embodiments of the orthopedic device to a joint, various contemplated embodiments of delivery systems manipulate the shape of the orthopedic device into a less-curved, or straightened configuration. In some instances, the orthopedic device can be completely straightened, and in others the orthopedic device may be curved in an arcuate configuration that is less curved, or has a larger major diameter, than the device as fully deployed in the joint. For example,FIG. 1A shows one embodiment of anorthopedic device100awith substantially straight configuration. Theorthopedic device100ahas aproximal end110aand adistal end120ain relation to insertion into the body of a patient, such as into a joint. In various embodiments of orthopedic devices discussed herein, the distal end of the orthopedic device is advanced or inserted into the body of a patient first, while the proximal end of the orthopedic device is initially inserted proximal to the distal end. In various embodiments, theorthopedic device100ahas various shape configurations to permit loading from a lumen within a needle, cannula, or other device for delivering the orthopedic device to the site for implantation. In one embodiment the straight configuration oforthopedic device100ais suited for delivery from a substantially straight needle. In other embodiment configurations, theorthopedic device100ais flexible and can be bent or biased to have a curve or other shape to permit delivery from curved or other-shaped needles or cannulae. In one embodiment theorthopedic device100ais delivered over a delivery structure.
• As illustrated, one embodiment of the orthopedic device has a relatively consistent width of the elongate device. However, in other contemplated embodiments, the width of the device body can vary along its length. For example, the orthopedic device can have a taper along a portion of its length, or be tapered along the device's entire length. Width, or other dimension, can vary from large to small or small to large, making the device thicker in some portions than in others.
• In one embodiment, theorthopedic device100ais made of a shape memory material. For example, the shape memory material can be made from a heat set/shaped shape-memory material, such as Nitinol or a shape memory plastic, polymeric, or synthetic material, such as polycarbonate urethane. For example, one embodiment of theorthopedic device100acomprises a shape memory material including a shape memory polyurethane or polyurethane-urea polymer. One example of this type of shape memory material is described in UnitedStates Patent Publication 2002/0161114 A1 entitled “Shape memory polyurethane or polyurethane-urea polymers” which is incorporated in its entirety by reference herein.Publication 2002/0161114 A1 describes a shape memory polyurethane or polyurethane-urea polymer including a reaction product of: (A) (a) silicon-based macrodiol, silicon-based macrodiamine and/or polyether of the formula (I): A—[(CH₂)_m—O—]_n—(CH₂)_m—A′, wherein A and A are endcapping groups; m is an integer of 6 or more; and n is an integer of 1 or greater; (b) a diisocyanate; and (c) a chain extender; or (B) (b) a diisocyanate: and (c) a chain extender, said polymer having a glass transition temperature which enables the polymer to be formed into a first shape at a temperature higher than the glass transition temperature and maintained in said first shape when the polymer is cooled to a temperature lower than the glass transition temperature, said polymer then being capable of resuming its original shape on heating to a temperature higher than the glass transition temperature. Various embodiments of the present invention relate to a shape memory polymer alone or a shape memory composition which includes a blend of two or more of the shape memory polyurethane or polyurethane-urea polymers defined above or at least one shape memory polyurethane or polyurethane-urea polymer defined above in combination with another material. The present invention further relates to processes for preparing materials having improved mechanical properties, clarity, processability, biostability and/or degradation resistance and devices or articles containing the shape memory polyurethane or polyurethane-urea polymer and/or composition defined above.
• In one embodiment theorthopedic device100acomprises anarticular layer105, which may also be called a blanket or a jacket. Thearticular layer105 is sized and configured to be placed within a body, such as in a joint as a layer between bones of the joint to provide a slideable articulation surface and/or a cushion. In one embodiment thearticular layer105 is configured to be compressed by loading in the joint. For example, in one embodiment an articular layer may be compressed from a substantially circular cross-sectional shape to an oval, elliptical, or football shaped cross-section, which further increases the amount of surface coverage of the articular layer with respect to bony joint contact, resulting in reduced pressure at the joint. In one embodiment the operating range of compression of an orthopedic device is in the range of 0 to 50% of the cross sectional diameter.
• In one embodiment the articular layer is made of a shape memory material, as described above. In certain embodiments of theorthopedic device100a, the body of theorthopedic device100aconsists only of an articular layer which has shape-memory properties. In other embodiments, as is described below, additional structures within the articular layer may also have shape memory characteristics. In certain embodiments, thearticular layer105 materials include but are not limited to Silicone, Teflon, Ultra High Molecular Weight Polyurethane or and any implantable grade material. In certain embodiments, thearticular layer105 can be compliant and or compressible or of a non-compressible construction. In certain embodiments, thearticular layer105 can for instance have a variety of durometers (material hardness). In certain embodiments, thearticular layer105 could also be infused with air bubbles becoming much like a sponge. In certain embodiments, thearticular layer105 can be provided in a number of shapes and be continuous or of interrupted/individual sections. In certain embodiments, thearticular layer105 may contain a material or a drug to inhibit inflammation, joint deterioration etc, or a material or drug to encourage tissue regeneration or device encapsulation. In certain embodiments thearticular layer105 comprises a cartilage replacement material or comprises a natural or synthetic cartilage.
• In certain embodiments, thearticular layer105 is coated with a drug such as a long lasting steroid. In certain embodiments the articular layer is provided with wells, pockets, bubbles or capsules for drug delivery. In one embodiment thearticular layer105 is coated with a secondary surface such as another polymer of a different material property or an antifriction high wear material such as Parylene or other similar materials which are known to the art as providing for a low friction surface.
• In certain embodiments, thearticular layer105 is radiopaque, providing for visibility of the device when implanted as viewed by X-Ray and/or other Fluoroscopic equipment. In one embodiment thearticular layer105 radiopacity is provided by radiopaque markers (not shown here) or by loading thearticular layer105 with platinum, gold or other biocompatible metal.
• As described above, in various embodiments the orthopedic device can be an arcuate configuration once it is implanted in a joint. Some non-limiting examples of arcuate configurations include an open hoop such as is shown in the embodiment inFIG. 1B, and a nautilus-style spiral as is shown in the embodiment inFIG. 1C. Referring toFIG. 1B, the open hoop arcuate configuration embodiment of theorthopedic device100bhas aproximal end110band adistal end120bin relation to insertion into the body of a patient, such as into a joint. In certain embodimentsorthopedic device100bhas many similar attributes and characteristics oforthopedic device100a, such as shape memory and/or anarticular surface105. In certain embodiments,orthopedic device100bis an arcuate configuration oforthopedic device100a. In certain embodiments the orthopedic device of100ais biased to the configuration as shown for orthopedic device of100b.The bias may be a preferred configuration for a flexible, pliable, bendable device. In certain embodiments the orthopedic device of100acan change to the configuration as shown for orthopedic device of100bby a change in ambient or implantation site temperature or the introduction of an activating medium or material. In certain embodiments, the orthopedic device is reversibly configurable between various shapes or geometries.
• In one embodiment theorthopedic device100bfloats inside the joint to better conform to the natural movement of the bones through the range of motion of the joint. In one embodiment the “open ring,” “hoop” or “coil” configuration oforthopedic device100bis designed to offer a mechanical advantage over that of fixed type prosthesis as in a total joint replacement as described above in the Background section. The design allows for the distribution of the loading, shearing and/or compressive forces seen by the articulation and or loading of the joint. As theorthopedic device100bis not a closed hoop, it is not fixed in place (e.g. attached to either end of bones in a joint) it in effect “floats” between the ends of the bones in a joint. Thus, theorthopedic device100boffers little to no resistance to shape change and can spring open or closed as force is applied to the device or to the joint, but still maintain the purpose of providing a bearing, cushion, slideable, or articulate surface. As there is little to no resistance to the shape change theorthopedic device100bin turn allows for the distribution of the forces and/or shear as well as resulting wear along the device more equally. In various arcuate configurations, such as a open circle or continuous spiral, embodiments of the orthopedic device are not closed like a complete ring or closed circular shape would be, resulting in increased dissipation of loading and compression though at least two deformations in the orthopedic device. First, an open ring allows for dynamic loading response as force that is applied to the joint is partially dissipated by the force necessary to radially-outwardly deform the open ring or spiral into a larger radius profile. In one embodiment the operating range of radial deformation of an arcuate orthopedic device is in the range of 0 to 50% of the orthopedic device profile diameter within the joint. Second, as discussed above, the compression of the articular layer resulting in cross-sectional deformation into a flatter shape also dissipates force or pressure in the joint.
• In one embodiment theorthopedic device100bis sized to snugly fit into the joint capsule itself. This fit maintains theorthopedic device100bcenter with respect to the axis of the bones of the joint, such as in a finger or a knuckle in one non-limiting example.
• In various embodiments theorthopedic device100bcomprises ends which are biased or bent slightly towards or away from its center (see e.g.,FIGS. 5B-5C,21A-21B). In one embodiment the orthopedic device, or coil, is out of plane on one or both ends, providing a secondary shock absorbing component to the orthopedic device as the bones in the joint are compressed axially. In one embodiment theorthopedic device100bis substantially flat, or planar.
• One example of a nautilus-style spiral arcuate configuration is the embodiment of anorthopedic device100cas shown inFIG. 1C. Theorthopedic device100chas aproximal end110cand a distal end120cin relation to insertion into the body of a patient, such as into a joint. In certain embodimentsorthopedic device100chas many similar attributes and characteristics oforthopedic device100aand/or100b, such as shape memory and/or anarticular surface105. In certain embodiments,orthopedic device100bis an arcuate configuration oforthopedic device100a. In certain embodiments the orthopedic device of100amay be altered in to a configuration as shown for orthopedic device of100c. The bias may be a preferred configuration for a flexible, pliable, bendable device. In certain embodiments the orthopedic device of100awhen unconstrained can change to the configuration as shown for orthopedic device of100c, or by a change in ambient or implantation site temperature or the introduction of an activating medium or material. In certain embodiments, the orthopedic device is reversibly configurable between various shapes or geometries.
• Theorthopedic device100cfloats inside the joint to better conform to the natural movement of the bones through the range of motion of the joint. The nautilus-style spiral arcuate configuration also offers the advantages outlined by the open hoop arcuate configuration, or hoop configuration, but provides a larger bearing surface to the joint. With the extended length of the spiral configuration, theorthopedic device100cis configured to provide more of an articulate surface, resulting in decreased pressure on the bones by dissipating forces over a larger surface area. The cross sectional diameter multiplied by the number of winds in a spiral shape roughly equals the surface area coverage of the articular surface in conformation with the bones of the joint. For example, a small cross sectional diameter of a spiral configuration allows for a plurality of windings in the spiral. This plurality of spiral windings can then adjust to the general surface area of either bone as the joint articulates.
• As described thus far, certain descriptions of embodiments of orthopedic devices have focused on the outside of the device. However, the inside of the devices can have additional structure. For example, inFIG. 2 anorthopedic device200 according to one embodiment of the present invention comprises anelongate core240 and anarticular layer230 surrounding at least a portion of thecore240. Referring back toFIGS. 1A-1C, various embodiments oforthopedic devices100a,100band/or100ccan either have an elongate core or lack an elongate core. In other embodiments oforthopedic devices100a,100band/or100ccan either have an articular layer or lack an articular layer. In other words, the orthopedic device may consist of an elongate core, an articular layer, or both.
• As illustrated in the embodiment of at leastFIG. 2 theorthopedic device200 includes theelongate core240 in addition to thearticular layer230. One preferred embodiment of theorthopedic device200 includes anelongate core240 and anarticular layer230 wherein one or both theelongate core240 and thearticular layer230 comprise a shape set memory material. In some embodiments thearticular layer230 can surround or encapsulate the entireelongate core240. In other embodiments thearticular layer230 surrounds, encapsulates, encloses or covers at least a portion of thecore240. As used herein, “surround,” “encapsulate” and “enclose” include configurations in which a core is not completely surrounded, completely encapsulated or completely enclosed. For example, certain embodiments of an orthopedic device contemplate an articular layer which “surrounds” an elongate core with a continuous or non-continuous helical band, discontinuous tabs, or other intermittent articular layer structure.
• In one embodiment thearticular layer230 is similar to any articular layer described herein. Likewise, in various embodiments, any articular layer may have some or all of the features of other articular layer embodiments described herein.
• In one embodiment theelongate core240 comprises a shape memory material. For example, theelongate core240 can comprise a shape memory material can made from a heat set/shaped shape-memory material, such as Nitinol or a shape memory plastic, polymeric, synthetic material. For example, one embodiment of theelongate core240 comprises a shape memory material including a shape memory polyurethane or polyurethane-urea polymer, as is described above. In one embodiment theelongate core240 comprises a metal “open” ring such as Nitinol encapsulated by anarticular layer230, or outer blanket, comprising silicone. In one embodiment theelongate core240 comprises a hardened polymer. In one embodiment theelongate core240 is configured such that a heat set Nitinol with an arcuate configuration, such as an open ring configuration, a horseshoe configuration, or a spiral configuration, can be straightened for delivery through cooling or plastic deformation, then recovered to its original heat-set shape once released from a delivery system, such as one embodiment using a properly sized hypodermic needle. In one embodiment theelongate core240 comprises a non-shape memory material which can be bent or deformed.
• In certain embodiments, theelongate core240 is coated or impregnated with a drug such as a long lasting steroid. In one embodiment theelongate core240 is coated with a secondary surface such as another polymer of a different material property or an antifriction high wear material such as Parylene or other similar materials which are known to the art as providing for a low friction surface.
• In one embodiment an orthopedic device comprises a removable elongate core and an articular layer. The removable elongate core can be any among the various elongate cores described herein. The orthopedic device would be inserted with an elongate core within the orthopedic device to keep the orthopedic device in a rigid substantially-straight or arcuate shape configuration. When placed in a target site such as a joint in a patient, the removable elongate core could be removed leaving the articular layer in place at the target site. In one embodiment the lumen left in the articular layer by the removal of the elongate core remains hollow allowing for compression, deformation, or cushioning of the joint by the orthopedic device's articular layer (see discussion relating toFIG. 18 below). This lumen, or center, could also be filled with a lumen material such as a liquid, polymer, collagen, or drug etc. The orthopedic device could be provided with a port or a valve at one or both ends to contain the lumen material. In one embodiment the lumen material is a liquid that can be configured, organized or hardened by the application of energy, radio frequency, laser, heat, cold, etc.
• The cross-section of some embodiments of orthopedic devices including an elongate core can have various non-limiting options, as are shown inFIGS. 3A-3E.FIG. 3A is a schematic cross-section of anorthopedic device300acomprising a substantially straight configuration. In this embodiment the device comprises anelongate core340aand anarticular layer330asurrounding at least a portion of the core340a. Thearticular layer330ahas aproximal end331aand adistal end332a.Theelongate core340ahas aproximal end341aand adistal end342a342a.In one embodiment theorthopedic device300ais similar to theorthopedic device100adescribed above.FIG. 3B shows a device anelongate core340band anarticular layer330bsurrounding at least a portion of the core340bin an open hoop arcuate configuration. Thearticular layer330bhas aproximal end331band adistal end332b. Theelongate core340bhas aproximal end341band adistal end342b.In one embodiment theorthopedic device300bis similar to theorthopedic device100bdescribed above. Certain embodiments of a spiral shaped device, such as is shown inFIG. 3C can have a single elongate core. For example,orthopedic device300ccomprises a nautilus-style spiral arcuate configuration, the device comprising anelongate core340cand anarticular layer330csurrounding at least a portion of the core340c. Thearticular layer330chas aproximal end331cand adistal end332c.Theelongate core340chas aproximal end341cand adistal end342c.In one embodiment theorthopedic device300cis similar to theorthopedic device100cdescribed above.
• In some embodiments, the elongate core can wrap around on itself or consist of a number of pieces, such as is shown inFIGS. 3D and 3E.FIG. 3D shows anorthopedic device300dwith an open hoop arcuate configuration. Thedevice300dcomprises one or moreelongate cores340dwrapped, braided or folded along a length of the device and anarticular layer330dsurrounding at least a portion of the core(s)340d. Thearticular layer330dhas aproximal end331dand adistal end332d.Theelongate core340dhas aproximal end341dand adistal end342d. In one embodiment theorthopedic device300dis similar to theorthopedic device100bdescribed above. In the illustrated embodiment inFIG. 3D, theelongate core340dis a unitary body. In other embodiments, two or moreelongate cores340dare situated in a roughly parallel or co-linear orientation, which can be twisted or braided or interlocked. Other embodiments of the orthopedic device need not be limited to a single elongate core or backbone, but could have a plurality of cores or backbones including a braided configuration, continuous overlaps, etc.FIG. 3E shows anorthopedic device300ewith a nautilus-style spiral arcuate configuration. Thedevice300ecomprises one or moreelongate cores340ewrapped or folded along a length of the device and anarticular layer330esurrounding at least a portion of the core(s)340e. In the illustrated embodiment inFIG. 3E, theelongate core340eis a unitary body. In other embodiments, two or moreelongate cores340eare situated in a roughly parallel or co-linear orientation, which can be twisted or braided or interlocked. Other embodiments of the orthopedic device need not be limited to a single elongate core or backbone, but could have a plurality of cores or backbones including a braided configuration, continuous overlaps, etc.
• The shape of the elongate core can vary, as is shown in embodiments inFIGS. 4A-4C.FIG. 4A shows anelongate core440awith one or more substantially linear or straight members.FIG. 4B shows an elongate core440bwith one or more wave, curve or zig-zag members that may be in one or more planes at any angle with respect to one another.FIG. 4C shows anelongate core440cwith one or more members in a braided or weave configuration. Any of these patterns can be used with any of the elongate cores disclosed herein.
• Various embodiments of elongate cores can have different features along the length or ends of the core, as is shown inFIGS. 5A-5C. Anelongate core540awith an open hoop arcuate configuration can have one or more end segments, as is shown inFIG. 5A. Such end segments can includeproximal end segment561aand/or distal end segment562a.In various embodiments, the elongate core orcores540acan have zero, one, two or more end segments. In one embodiment theend segment561aor562ais radiopaque or can be used as a marker for visualization of the ends of the orthopedic device. Theelongate core540ahas aproximal end541aand adistal end542a. In one embodiment theend segments561aand562aare spherical bodies. In another embodiment, theend segments561aand562aare loops. In one embodiment theend segments561aand562aextend from the same material as the length of theelongate core540a. In one embodiment theend segments561aand562aare separate elements made of the same or different material as the length of theelongate core540aand which are bonded, fused, welded, glued, or otherwise attached to theproximal end541 a and adistal end542a, respectively. Although not illustrated, it is contemplated that anelongate core540ahas one or more medial segments anywhere along the length of theelongate core540a. In various embodiments,elongate core540ahas end segments or medial segments to help improve stability of an articular layer or outer blanket, and need not be flat or planar, but can be biased out of the primary plane of the device at one end or both ends.
• Oneelongate core540bembodiment includes one or more bends, such asproximal bend541band/ordistal bend542bas shown inFIG. 5B. In various embodiments, the bends can also be called hooks. In various embodiments, the bends or hooks can be closed off to form a loop, as with certain embodiments ofelongate core540a. Alternately,elongate core540chas one or more segments bent in or out of the primary plane of the device as shown inFIG. 5C. In one embodimentproximal segment541cis bent radially inward from the curvature of theelongate core540c. In one embodimentdistal segment542cis bent radially outward from the curvature of theelongate core540c.In other embodiments,proximal segment541cand/ordistal segment542care bent radially inward, radially outward, and/or up or down from the primary plane of theelongate core540c.
• Elongate cores can have any of a variety of cross-sectional structures or profiles. For example, some embodiments of elongate cores cross-sections are shown inFIGS. 6A-6K. The illustrated embodiments are not limiting, but merely examples of various possible cross-sectional profiles of any of the embodiments of elongate cores or orthopedic devices described herein. The illustrated embodiments shows a variety of possible cross-sectional shapes for embodiments of the device or the core of the device, including a square, ellipse, triangular, etc., and wherein the elongate core can be modified by twisting, abrading, pitting and zigzagging, etc.
• FIG. 6A illustrates a cross-sectional view of an embodiment of a circular profileelongate core640a, which can be rotated along a longitudinal axis of the core640a. In various embodiments theelongate core640ais at least partially surrounded by an articular layer, wherein theelongate core640aand/or the articular layer actuate between a straight or slightly curved configuration to a more curved or arcuate configuration. During this change in configuration,elongate core640aand the articular layer may rotate with respect to each other. In one embodiment theelongate core640aand the articular layer has some frictional engagement, which may interfere with rotation between the elements, resulting in some level of deformation. Furthermore, in one embodiment both theelongate core640aand the articular layer will have different material properties which are dependent on stiffness, durometer and other aspects of the respective materials. Depending on the desired orientation of an orthopedic device during delivery to a joint, the orientation of theelongate core640aand/or the articular layer may be controlled by the configuration of the delivery device being used.
• In various embodiments, an elongate core may be configured to limit deformation and/or rotation in various orientations during a change in configuration between straightened and curved profiles.FIG. 6B illustrates a cross-sectional view of an embodiment of a triangular profile elongate core640b, which can limit rotation of an articular layer along a longitudinal axis of the core640b.FIG. 6C illustrates a cross-sectional view of an embodiment of a rectangular profileelongate core640c, which can limit rotation of an articular layer a longitudinal axis of the core640c.FIG. 6D illustrates a cross-sectional view of an embodiment of a trapezoidal profileelongate core640d, which can limit rotation of an articular layer along a longitudinal axis of the core640d.FIG. 6E illustrates a cross-sectional view of an embodiment of an oval or elliptical profileelongate core640e, which can limit rotation of an articular layer along a longitudinal axis of the core640e.FIG. 6F illustrates a cross-sectional view of an embodiment of a ridged profileelongate core640f, which can limit rotation of an articular layer along a longitudinal axis of the core640f.FIG. 6G illustrates a cross-sectional view of an embodiment of a non-symmetric profile elongate core640g, which can limit rotation of an articular layer along a longitudinal axis of the core640g.FIG. 6H illustrates a cross-sectional view of an embodiment of a cross or X-profileelongate core640h, which can limit rotation of an articular layer along a longitudinal axis of the core640h.FIG. 6I illustrates a cross-sectional view of an embodiment of a lumen profile elongate core640i, which can limit rotation of an articular layer along a longitudinal axis of the core640i.FIG. 6J illustrates a cross-sectional view of an embodiment of a pentagon profileelongate core640j, which can limit rotation of an articular layer along a longitudinal axis of the core640j.FIG. 6K illustrates a cross-sectional view of an embodiment of a hexagon profileelongate core640k, which can limit rotation of an articular layer along a longitudinal axis of the core640k.
• Some embodiments of an elongate core include a plurality of interconnectable discrete elongate members, such as is shown inFIGS. 7-9C. In various embodiments, two or more discrete elongate members may be connected along a single core wire, a series of core wires, or connectors. In one embodiment one or more discrete elongate members can rotate or spin about the connector or core wire. In another embodiment one or more discrete elongate members are affixed to the connectors or core wire in a manner to reduce or prevent rotation of the elongate members with respect to connector or core wire. As illustrated inFIG. 7A one embodiment of anorthopedic device740acomprising a plurality of interconnectable discrete elongate members haselongate members742,744 and746 which are linked byconnector760. In various embodiments theconnector760 can be a single core member extending between all the discrete elongate members, or it can be any number of discrete connecting members between the elongate members. In one embodiment, anorthopedic device740bwith a plurality of independent or interconnectable discrete elongate members can have a “W”-shaped generally rectilinear configuration. Theconnectors760 can be configured to orient the elongate members such as742,744,746 and748 in any number of orientations or angles. In various embodiments theconnectors760 can have shape memory configurations or biases for particular orientations depending on the doctor's preference or the device selected. The overall shape of an orthopedic device can have any number of configurations: for example, at least a “C”, “O” and “W” shape have been mentioned, but the device and/or articular layer and/or elongate core can be in any shape or configuration. The device is not limited to the “C”-shape or a spiral shape.
• An elongate core may comprise a plurality of discrete members of one of various shapes and sizes, wherein the discrete members may be interconnected to function as an elongate core or a backbone as set forth herein. Likewise,FIG. 8 showsorthopedic device840 withinterconnected members841,842, and843 which are linked by anextendable connector860.
• One embodiment of anelongate core940awith a plurality of interconnectable discrete members, orlinks950a, in a substantially straight configuration is shown inFIG. 9A.Elongate core940amay be described as a multi-link elongate core, multi-link core, multi-link orthopedic device, or multi-link orthopedic implant. In one embodiment of a multi-link orthopedic device a series of rigid or flexible links are configured to translate the multi-link core from a straight or slightly curved configuration into a curved orientation or configuration. The diameter of curvature of the device could be adjustable by the ratcheting features provided on eachlink950a. In one embodiment thelinks950aare made of a material that can undergo some level of elastic deformation. In another embodiment, thelinks950aare made of a more rigid material. With embodiments of the device, core, or link that are made from a super elastic material such as Nitinol, the implant can be straightened from its curved, deployed or implanted configuration and placed in a needle or cannula. However, a less elastic material such as stainless steel or certain plastics might yield or break if straightened that much. Using a curved delivery system, such as one shown inFIG. 10C below, would allow a more-rigid arcuate implant to be slightly straightened enough for insertion, but not enough to cause yielding.
• Looking closer at a link,FIG. 9B shows a side view of one link950b. In one embodiment link950bis alink950aofFIG. 9A. In one embodiment link950bcomprises afirst end951 and asecond end952. Various links950bare interconnectable between thesecond end952 of a first link950band thefirst end951 of a second link950b′, and in one embodiment the interconnection is a hinged connection between afirst link interface990 and asecond link interface980. In one embodiment thefirst link interface990 is a post and thesecond link interface980 is a channel in which the post is captured to allow rotation. In another embodiment, thesecond link interface980 is a post and thefirst link interface990 is a channel in which the post is captured to allow rotation. In various other embodiments, other link interfaces allowing some rotation including snap fits, connectors, or other similar interfaces may be used. In the illustrated embodiment, the link950bcomprises aratchet prong960 and ratchetteeth970. Theratchet teeth970 of one link950binteract with theratchet prong960 of a second link950b′ to allow rotation with respect to links950band950b′ while restricting or limiting rotation in the opposite direction.
• Various link embodiments can be configured to an arcuate configuration, as inFIG. 9C showing anelongate core940cwith links according toFIG. 9A in an arcuate open loop configuration. In one embodiment theelongate core940cis actuated and locked into an arcuate configuration by the ratcheting mechanism as described above. In one embodiment the ratchet locking is configured to be disengageable such that the prong is releasable from the teeth to allow theelongate core940cto rotate in a straight or less-curved configuration.
2. Method and Apparatus for Delivering Implantable Orthopedic Devices
• In various embodiments of orthopedic devices described herein, the orthopedic devices are configured to have an arcuate shape in a joint. In certain embodiments, the orthopedic device can be straightened into a substantially straight or less-curved configuration for implantation with an orthopedic device delivery system. For example, in one embodiment an arcuate orthopedic device can be straightened by cooling or chilling a shape-memory material in the orthopedic device and then inserting the orthopedic device into a tube, cannula, or hypodermic needle of specific design shape and cross section. The pre-loaded hypodermic needle is then attached to a handle through a coupling or interface such as a luer lock standard to the industry or any other attachment means. The physician then straightens the finger by applying force providing for a space or gap to occur in the joint. For example, the force can be provided by using his hands, or a tool, to pull, stretch or spread the desired joint. In one embodiment a sharp tool such as a scalpel or trocar can be used to pierce the joint tissue. In another embodiment, the deliver device needle can pierce the joint tissue. The needle is positioned mid-point between the posterior and anterior surfaces of the joint. The tip of the needle is advanced into the joint, completely within the joint capsule. Once inserted the physician releases the device by advancing it out of the needle using an advancing mechanism, such as a handle and plunger. Once deployed the needle and handle can be removed from the joint. If more than one joint, such as a knuckle, is treated the deployed needle can be removed via the luer type connector and a second attached to the same handle, repeating the procedure as needed.
• One orthopedicdevice delivery system1000 comprising ahandle1010 and aplunger1020 that is suitable for delivering the orthopedic device implant is shown inFIG. 10A. In various embodiments, the orthopedicdevice delivery system1000 can be provided in a number of mechanical configurations. One objective of the orthopedicdevice delivery system1000 is to completely advance the orthopedic device out of a channel, cannula, lumen, or needle, with non-limiting examples illustrated inFIGS. 10B and 10C. In various embodiments, the orthopedicdevice delivery system1000 is actuated by advancing the orthopedic device by a simple ram type piston or hypodermic needle configuration, or through the use of a lead screw, or through the use of a pneumatic or hydraulic type mechanism. In the illustrated embodiment, thehandle1010 comprises adistal handle region1012 and aproximal handle region1011 and theplunger1020 comprises adistal plunger region1022 and aproximal plunger region1021. In one embodiment thedistal handle region1012 comprises acannula interface1015, such as a luer connector.
• Embodiments of a cannula or needle can be straight or curved, as inFIGS. 10B and 10C respectively. A substantiallystraight cannula1030bor needle with alumen1035bis suitable for delivering the orthopedic device implant described herein in conjunction with the orthopedicdevice delivery system1000 ofFIG. 10A. In one embodiment thecannula1030bcomprises adistal cannula region1032band aproximal cannula region1031b.In one embodiment thedelivery cannula1030bcan be attached to ahandle1010 in an orthopedic device delivery system such as orthopedicdevice delivery system1000 with any of a number of attachment means such as a standard luer type coupler, bayonet, a luer mount, or a thread type means for attachment to thedelivery handle1010. In one embodimentproximal cannula region1031bcomprises aflange1038band aluer connector1037b.The needle ordeployment cannula1030bcan be provided in many shapes and cross sections. In one embodiment thecannula1030bis sized and configured to interface with the orthopedic device in a specific orientation for delivery into a joint. This interface may be a key-slot, or other mechanical interface. In one embodiment thedistal cannula region1032bis provided at its distal end with an insertion feature such as a point, knife edge or blunt atraumatic edge.
• Another embodiment of orthopedic device delivery system comprising anarcuate cannula1030cor curved needle is shown inFIG. 10C. It has alumen1035cis suitable for delivering the orthopedic device implant described herein in conjunction with the orthopedicdevice delivery system1000 ofFIG. 10A. In various embodiments,arcuate cannula1030cis similar to substantiallystraight cannula1030b, except thatarcuate cannula1030cis more curved. In one embodiment thecannula1030ccomprises adistal cannula region1032cand aproximal cannula region1031c.In one embodiment thedelivery cannula1030ccan be attached to ahandle1010 in an orthopedic device delivery system such as orthopedicdevice delivery system1000 with any of a number of attachment means such as a standard luer type coupler, bayonet, a luer mount, or a thread type means for attachment to thedelivery handle1010. In one embodimentproximal cannula region1031ccomprises aflange1038cand aluer connector1037c.The needle ordeployment cannula1030ccan be provided in many shapes and cross sections. In one embodiment thecannula1030cis sized and configured to interface with the orthopedic device in a specific orientation for delivery into a joint. This interface may be a key-slot, or other mechanical interface. In one embodiment thedistal cannula region1032cis provided at its distal end with an insertion feature such as a point, knife edge or blunt atraumatic edge.
• In some embodiments the process or method of inserting an orthopedic device into a joint is preferably atraumatic. In one embodiment a fluoroscopically placed stab incision is followed by a cannula insertion for orthopedic device delivery. The stab incision would by its nature provide a path for a delivery needle or cannula to follow. The stab incision could or would remove the necessity for the cannula tip to be sharp. For example, In one embodiment a joint such as a knuckle can be physically identified for orthopedic device placement. The device can be fluoroscopically placed or inserted without fluoroscopy. A cannula is inserted into the stab incision and the orthopedic device is delivered through the cannula in the incision to the joint.
• Looking more closely at the tip of a needle or cannula,FIGS. 10D and 10E illustrate two potential options. A blunteddelivery cannula1030dwith alumen1035dis shown inFIG. 10D. In certain embodiments, the blunteddelivery cannula1030dis used in conjunction with a joint piercing tool (not illustrated here) such as a knife, scalpel, spike, trocar, or other sharp instrument for piercing tissue surrounding a joint in order to create an access hole or port through which a cannula can be inserted to provide the orthopedic device access to a joint. Anangular tip1030ewith alumen1035eis shown inFIG. 10E. In one embodiment theangular tip1030eis sharp enough to pierce tissue surrounding a joint in order to create an access hole or port through which a cannula can be inserted to provide the orthopedic device access to a joint. In another embodiment, theangular tip1030eis atraumatic and is used to guide the delivery device in a previously opened incision or natural opening in tissue. Minimally or atraumaticdistal cannula regions1032b,1032ccorresponding to any cannula, such ascannula1030b-E are intended to be slid through the stab incision, such as made by a scalpel, thereby spreading the tissue which makes up the knuckle capsule as it goes in.
• As described above, in various embodiments an elongate core is at least partially surrounded by an articular layer, wherein the elongate core and/or the articular layer actuate between a straight or slightly curved configuration to a more curved or arcuate configuration. During this change in configuration, elongate core and the articular layer may rotate with respect to each other. In one embodiment the elongate core and the articular layer has some frictional engagement, which may interfere with rotation between the elements, resulting in some level of deformation. Furthermore, in one embodiment both the elongate core and the articular layer will have different material properties which are dependent on stiffness, durometer and other aspects of the respective materials. Depending on the desired orientation of an orthopedic device during delivery to a joint, the orientation of the elongate core and/or the articular layer may be controlled by the configuration of the delivery device being used. In various embodiments, the shape, curvature, or tip of the cannula, needle, or lumen can be configured to control the specific orientation of the orthopedic device as it is being implanted. For instance, the point of a needle, trocar, or angle-tipped cannula such as an orthopedic device delivery system with anangular tip1030ecould be used to define the relationship of the orthopedic device and its orientation in a joint.
• One way of delivering embodiments of the orthopedic device is shown inFIG. 11, where an implantableorthopedic device1100 is advanced through acannula1110 by aplunger1120. Theorthopedic device1100 comprises adistal end1102 and aproximal end1101, and is similar to the embodiments of orthopedic devices described herein. Thecannula1110 has adistal end1112 which is configured to present theorthopedic device1100 into the implant delivery site in a joint in the proper orientation. Theplunger1120 has adistal end1122 which advances theorthopedic device1100 out of thecannula1110 and into the joint. In the illustrated embodiment, thedistal end1122 of theplunger1120 pushes theproximal end1101 of theorthopedic device1100. In one embodiment the plunger is sized to match the cross sectional diameter of the proximal end of the device and can also be provided with features to engage the device in a specific fashion. In other embodiments (not illustrated) the plunger is configured to attach to a distal or medial portion of the orthopedic device to pull or advance the device out of the cannula. In one embodiment the orthopedic device delivery system is configured to deliver theorthopedic device1100 in an orientation within a plane (“primary plane”) roughly corresponding to a plane of bony or cartilaginous articulation within a joint, which is roughly orthogonal to a longitudinal axis of at least one bone comprising part of the joint. As an orthopedic device is delivered into a joint, such as a knuckle, the tissue surrounding the knuckle including a joint capsule and various ligaments helps maintain the orientation of the orthopedic device in or near the primary plane within the joint by containing the orthopedic device around its outer periphery. In one embodiment an angular tip at thedistal end1112 of thecannula1110 helps maintain the proper orientation of theorthopedic device1100 within or near the primary plane and avoiding undesired bias or deformation of theorthopedic device1100.
• Some of the steps in delivering anorthopedic device1200 in a joint with an orthopedic device delivery system are illustrated inFIGS. 12A-15B. In these figures a joint comprises afirst bone1201, asecond bone1202, andtissue1203 surrounding the joint, such as a joint capsule and/or a ligament. The “A” figures illustrate a side view of the joint and the “B” figures illustrate a cross-sectional view orthogonal to the side view in “A.” The primary plane of the orthopedic device roughly corresponds to the plane of the “B” whenbones1201 and1202 are roughly linear. When thebones1201 and1202 actuate with respect to each other, the primary plane may actuate as well to roughly correspond to a plane normal to a point of contact between thebones1201 and1202 with theorthopedic device1200. Acannula1230 with adistal end1232 and alumen1235 is shown in both views. In the illustrated embodiment, thedistal end1232 of thecannula1230 comprises a feature which helps maintain the proper orientation of the orthopedic device during delivery. As shown, one embodiment of thedistal end1232 feature is an angled tip. In each ofFIGS. 12B,13B,14B and15B, two embodiments of acannula1230band1230care illustrated. One would be used at a time, but both are illustrated (withcannula1230bin solid lines and1230cin dotted lines) to demonstrate that a straight or curved cannula, respectively, can be used to deliver the orthopedic device as described with respect toFIGS. 10B and 10C above. Aplunger1250 advances theorthopedic device1200 into the joint using any of the advancing mechanisms described herein.
• A step showing the device prior to implantation is shown inFIGS. 12A-12B. This illustration shows both a substantiallystraight cannula1230band another embodiment comprising anarcuate cannula1230c.A step illustrating at least partial insertion of theorthopedic device1200 into the joint is shown inFIGS. 13A-13B. In one embodiment a tool (not illustrated) is used to pierce thetissue1203 with a stab incision prior to insertion of thecannula1230. In another embodiment, thecannula1230 pierces thetissue1203. Theplunger1250 advances theorthopedic device1200 into the joint. Deployment of the device into the joint is shown inFIGS. 14A-14B. Theorthopedic device1200 is shown in an arcuate configuration. The deployment of theorthopedic device1200 into the joint and removal of the delivery cannula(e)1230bor1230cis illustrated inFIGS. 15A-15B.
• Other embodiments of orthopedic devices can have additional features which can control the extent to which a device is open or closed. For example, oneorthopedic device1600 comprising atether1610 and aloop structure1620 is shown in a substantially straight configuration inFIG. 16A. In one embodiment, theorthopedic device1600 exhibits similar characteristics as the previously described devices discussed herein. For example, the straight configuration of thedevice1600 may correspond to a configuration used for device delivery. In a normal state, thedevice1600 may be an open ring, arcuate shape, or other configuration or shape when it is not being straightened for delivery or removal. Theorthopedic device1600 comprises aproximal end1601 and adistal end1602. Theproximal end1601 comprises thetether1610 and adistal end1602 comprises theloop structure1620. Thetether1610 can be a lanyard, suture, wire, or other structure which in one embodiment is unitary with theorthopedic device1600. In one embodiment thetether1610 is unitary with an elongate core in theorthopedic device1600. Thetether1610 passes through theloop structure1620. After theorthopedic device1600 is deployed in a joint it assumes an arcuate configuration as shown inFIG. 16B. In one embodiment thetether1610bis pulled tight to bring theproximal end1601 anddistal end1602 of theorthopedic device1600 toward each other and thetether1610bis tied into a knot, plug, mechanical fastener orother securing mechanism1630bto form a substantially closed ring configuration for theorthopedic device1600b.Depending on the degree of desired openness in the arcuate configuration of theorthopedic device1600, thetether1610bcan be pulled and locked at different lengths to create a desired hoop or device size. Once the desired size is attained, thesecuring mechanism1630bis locked. Thetether1600bcan then be cut proximate to the proximal side of thesecuring mechanism1630b.Thetether1600bcan also be cut for retrieval of the device from the joint. In another embodiment anorthopedic device1600ccomprises one or more tethers, such astethers1610cand1612cas shown inFIG. 16C. In one embodiment thetethers1610cand1612care secured to each other with asecuring mechanism1630csuch as is described with respect to securingmechanism1630b.Thetethers1610cand1612ccan then be cut proximate to the proximal side of thesecuring mechanism1630c.Thetether1610cand/or1612ccan also be cut for retrieval of the device from the joint.
• Another embodiment of anorthopedic device1700 includes a loopedarcuate configuration1710 and at least one anchor, as is shown inFIG. 17. Theorthopedic device1700 has aproximal end1701 and adistal end1702. In one embodiment theproximal end1701 anddistal end1702 are crossing ends on substantially the same axis. In one embodiment theorthopedic device1700 has aproximal anchor1720 at theproximal end1701 and adistal anchor1730 thedistal end1702.Orthopedic device1700 has a substantially straight or less-curved configuration (not illustrated) for delivery. Once theorthopedic device1700 is delivered to the joint, it reverts to its loopedarcuate configuration1710. In various embodiments, theanchors1720 and1730 are unitary and formed with an elongate core in theorthopedic device1700, are unitary and formed with the an articular layer in theorthopedic device1700, or are formed of separate elements and attached to theorthopedic device1700. In various embodiments theanchors1720 and/or1730 are threaded, tapered, cylindrical, barbed, hooks, ribs, dissolvable, drug eluting and/or non-symmetric. In one embodiment theanchors1720 and/or1730 are roughly cylindrical and configured to be releasably attachable with a tool or plunger. In one embodiment theanchors1720 and/or1730 are impregnated with a bonding material. In one embodiment theanchors1720 and/or1730 are secured in to tissue surrounding or in the joint, such as bone, cartilage, a capsule or ligaments. In one embodiment theanchors1720 and/or1730 are bio-absorbable into surrounding tissue.
• Retrieval of orthopedic devices is also contemplated. For example, one orthopedic device delivery andretrieval system1801 can grab an implantableorthopedic device1800 and pull it through acannula1830 using asnare1850, as is illustrated inFIG. 18. Orthopedic device delivery andretrieval system1801 is configured to deploy and/or retrieve the implantableorthopedic device1800. In one embodiment thecannula1830 is part of a separate retrieval system with a lumen sufficiently sized and configured to recapture and retrieve a deployedorthopedic device1800. In various embodiments theorthopedic device1800 has end segments or medial segments along theorthopedic device1800 articulate layer and/or elongate core, such as is illustrated inFIGS. 5A-5C. In one embodiment theorthopedic device1800 comprises one or more snare interface points such asend segments561aand562adescribed with respect toFIGS. 5A-5B above. For example, endsegments561aand562acan be a ball, sphere, bead, hook, loop or other feature which can be ensnared by a tightenedsnare1850 to pull theorthopedic device1800 out of the joint. In one embodiment the snare interface point is radiopaque or has markers for fluoroscopic visualization during the retrieval procedure. In one embodiment thesnare1850 is attached (not illustrated) to a handle or control device proximal to thecannula1830. For example in one embodiment thesnare1850 is attached to a handle or plunger with can be withdrawn or pulled with respect to thecannula1830 to tighten thesnare1850 and pull the orthopedic device out of the joint and out of the patient's body.
• In one embodiment of an orthopedicdevice retrieval system1801 the distal end of thecannula1830 comprises a hook (not illustrated) which can be used to grab or retrieve an orthopedic device. In one embodiment the cannula hook is actuatable by the doctor by pressing a button to extend or rotate the hook into the joint, which then connects or grabs a part of the orthopedic device for retrieval. In an additional embodiment, the button can be released to pull the hook back into place to lock on to the orthopedic device to be recaptured. In one embodiment of an orthopedicdevice retrieval system1801 only an elongate core is retrieved, leaving the articular layer in the joint in a manner similar to that discussed above regardingFIG. 2.
• Another orthopedicdevice retrieval system1901 can retrieve an implantableorthopedic device1900 with aplunger1950 connectable with adevice interface1910, as is shown inFIGS. 19A-19B. In one embodiment thedevice interface1910 is a junction with a male threadedsection1911 on the distal end of theplunger1950 and a female threadedsection1912 on the proximal end of theorthopedic device1900. In one non-illustrated embodiment thedevice interface1910 is a junction with a female threadedsection1912 on the distal end of theplunger1950 and a male threadedsection1911 on the proximal end of theorthopedic device1900. In one embodiment the minor diameter of the threads of the male threadedsection1911 is roughly the same as the outer diameter of the plunger or orthopedic device. In one embodiment the major diameter of the threads of the male threadedsection1911bis less than the outer diameter of the plunger or orthopedic device resulting in a step at1911bto provide uniform contact with theorthopedic device1900.
• Another orthopedic device retrieval system can remove an implantableorthopedic device2000 using aplunger2050 connectable with adevice interface2010, as is shown inFIGS. 20A-20C. In one embodiment thedevice interface2010 is a junction withclosed jaws2052aat a distal end of theplunger2050 and ajaw interface2002 on the proximal end of theorthopedic device2000. In one embodiment thejaw interface2002 comprises astep2005 for grasping or locking on to thejaw interface2002. Thestep2005 can be a linear, circumferential, or other feature for grasping with the jaws. In various embodiments thejaw interface2002 comprises a portion of anarticular layer2003, a portion of anelongate core2004, or, as illustrated inFIG. 20C, both a portion of anarticular layer2003 and a portion of anelongate core2004 according to various embodiments of elongate cores and articular layers described herein. In one embodiment with thejaw interface2002 comprising a portion of theelongate core2004, theelongate core2004 is exposed at thejaw interface2002. Theclosed jaws2052acan be actuated intoopen jaws2052bto release theorthopedic device2000 into a joint. Conversely, theopen jaws2052bcan be actuated into a closed configuration asclosed jaws2052ato recapture theorthopedic device2000 from the joint. In oneembodiment jaws2052aand2052bare spring loaded. In alternative embodiments, thedevice interface2010 comprises a solenoid, linkage, ring mechanism, push-pin, snap-fit, and ball-detent interface. In one embodiment thedevice interface2010 is an electrolyte junction whereby the application of energy, such as electricity, causes the junction to dissolve thereby breaking the junction between theplunger2050 and theorthopedic device2000.
• FIGS. 21A-21C illustrate non-limiting embodiments of orthopedic devices which may exhibit similar characteristics of other orthopedic devices described above.FIGS. 21A and 21B illustrateorthopedic devices2100aand2100b, respectively, which have a multi-planar configuration which may be similar to the devices illustrated inFIGS. 1C and 1B orFIG. 3C or3B. Here, the devices show a characteristic demonstrating that the devices do not have to be constrained in a single plane.FIG. 21C is a schematic side view of anorthopedic device2100caccording to one embodiment of the present invention comprising a “W”-shaped generally rectilinear configuration. This embodiment further demonstrates devices that are not limited to arcuate configurations.
• It will be understood that the foregoing is only illustrative of the principles of the invention, and that various modifications, alterations, and combinations can be made by those skilled in the art without departing from the scope and spirit of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims.

Claims (25)

1. An orthopedic device suitable for minimally invasive deployment using a tubular delivery apparatus, the orthopedic device comprising an elongate core having a proximal end and a distal end, the core comprising a generally arcuate configuration at substantially body temperatures to enhance self-centering positioning of the orthopedic device when deployed, said core being manipulatable into a substantially straight configuration to permit delivery.

2. The orthopedic device ofclaim 1, further comprising an articular layer surrounding at least a portion of the core.

3. The orthopedic device ofclaim 1, wherein the core comprises shape memory material.

4. The orthopedic device ofclaim 1, wherein the generally arcuate configuration comprises a spiral shape.

5. The orthopedic device ofclaim 1, wherein the core, when in a generally arcuate configuration, is substantially non-planar.

6. The orthopedic device ofclaim 2, wherein the device is further configured to permit at least partial removal of at least part of the core from the articular layer resulting in a void within the articular layer.

7. The orthopedic device ofclaim 6, wherein the device is further configured so that at least part of the void created by removal of at least part of the core may be partially filled with a polymer material.

8. The orthopedic device ofclaim 2, wherein the articular layer is a polymeric material.

9. The orthopedic device ofclaim 1, further comprising a coating of antifriction high wear material on a surface of said device.

10. The orthopedic device ofclaim 1, further comprising at least a second core.

11. An orthopedic device suitable for minimally invasive deployment using a tubular delivery apparatus, the orthopedic device comprising an elongate core having a proximal end and a distal end, the elongate core comprising a generally rectilinear configuration at substantially body temperatures to enhance self-centering positioning of the orthopedic device when deployed, said elongate core being manipulatable into a substantially straight configuration to permit delivery.

12. The orthopedic device ofclaim 11, further comprising an articular layer surrounding at least a portion of the core.

13. The orthopedic device ofclaim 11, wherein the core comprises shape memory material.

14. The orthopedic device ofclaim 11, wherein the core, when in a generally rectilinear configuration, is substantially non-planar.

15. The orthopedic device ofclaim 12, wherein the device is further configured to permit at least partial removal of at least part of the core from the articular layer resulting in a void within the articular layer.

16. The orthopedic device ofclaim 15, wherein the device is further configured so that at least part of the void created by removal of at least part of the core may be partially filled with a polymer material.

17. The orthopedic device ofclaim 12, wherein the articular layer is a polymeric material.

18. The orthopedic device ofclaim 11, further comprising a coating of antifriction high wear material on a surface of said device.

19. The orthopedic device ofclaim 11, further comprising at least a second core.

20. A method of treating an orthopedic joint comprising using a tubular delivery apparatus to minimally-invasively deploy an orthopedic device suitable so that the device forms a substantially non-linear pre-formed configuration in situ at substantially body temperatures to enhance self-centering positioning of the orthopedic device when deployed.

21. The method of treating an orthopedic joint ofclaim 20, further comprising inserting an apparatus at or proximal the situs of deployment to remove at least a portion of the device.

22. The method of treating an orthopedic joint ofclaim 20, further comprising creating a gap in the orthopedic joint.

23. The method of treating an orthopedic joint ofclaim 20, wherein the tubular delivery apparatus comprises a curved channel.

24. The method of treating an orthopedic joint ofclaim 20, further comprising inserting an apparatus at or proximal the situs of deployment to remove at least a portion of the core.

25. The method of treating an orthopedic joint ofclaim 20, wherein the substantially non-linear pre-formed configuration is rectilinear.

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