US20040260293A1 - Fixation system with multidirectional stabilization pegs - Google Patents

Abstract

A fixation system includes a plate intended to be positioned against a bone, a plurality of bone screws for securing the plate along an non-fractured portion of the bone, and a plurality of bone pegs which extend from the plate and into bone fragments of the fracture to provide a supporting framework. The pegs can be oriented at various angles relative to an axis normal to the lower surface of the plate. For each peg, once the peg has been appropriately positioned within the peg hole, a set screw is threaded into the peg hole and tightened, thereby securing the peg in the selected orientation.

Description

• This application is a continuation-in-part of U.S. Ser. No. 09/735,228, filed Dec. 12, 2000, which is a continuation-in-part of both U.S. Ser. No. 09/524,058, filed Mar. 13, 2000 and U.S. Ser. No. 09/495,854, filed Feb. 1, 2000, all of which are hereby incorporated by reference herein in their entireties.[0001]
BACKGROUND OF THE INVENTION
• 1. Field of the Invention[0002]
• This invention relates broadly to surgical devices. More particularly, this invention relates to a bone fixation system having multidirectional bone fragment support pegs.[0003]
• 2. State of the Art[0004]
• Referring to FIG. 1, a Colles' fracture is a fracture resulting from compressive forces being placed on the distal radius[0005]10-, and which causes backward displacement of thedistal fragment12 and radial deviation of the hand at thewrist14. Often, a Colles' fracture will result inmultiple bone fragments16,18,20 which are movable and out of alignment relative to each other. If not properly treated, such fractures result in permanent wrist deformity. It is therefore important to align the fracture and fixate the bones relative to each other so that proper healing may occur.
• Alignment and fixation are typically performed by one of several methods: casting, external fixation, interosseous wiring, and plating. Casting is non-invasive, but may not be able to maintain alignment of the fracture where many bone fragments exist. Therefore, as an alternative, external fixators may be used. External fixators utilize a method known as ligamentotaxis, which provides distraction forces across the joint and permits the fracture to be aligned based upon the tension placed on the surrounding ligaments. However, while external fixators can maintain the position of the wrist bones, it may nevertheless be difficult in certain fractures to first provide the bones in proper alignment. In addition, external fixators are often not suitable for fractures resulting in multiple bone fragments. Interosseous wiring is an invasive procedure whereby screws are positioned into the various fragments and the screws are then wired together as bracing. This is a difficult and time consuming procedure. Moreover, unless the bracing is quite complex, the fracture may not be properly stabilized. Plating utilizes a stabilizing metal plate typically against the dorsal side of the bones, and a set of parallel pins extending from the plate into the holes drilled in the bone fragments to provide stabilized fixation of the fragments. However, the currently available plate systems fail to provide desirable alignment and stabilization.[0006]
SUMMARY OF THE INVENTION
• It is therefore an object of the invention to provide an improved fixation and alignment system for a Colles' fracture and other fractures.[0007]
• It is another object of the invention to provide a fixation system which desirably aligns and stabilizes multiple bone fragments in a fracture to permit proper healing.[0008]
• It is also an object of the invention to provide a fixation system which is highly adjustable to provide a customizable framework for bone fragment stabilization.[0009]
• In accord with these objects, which will be discussed in detail below, a fracture fixation system is provided which generally includes a plate intended to be positioned against a non-fragmented proximal portion of a fractured bone, a plurality of bone screws for securing the plate along the non-fragmented portion of the bone, and a plurality of bone pegs coupled to the plate and extending therefrom into bone fragments adjacent the non-fragment portion.[0010]
• According to a preferred embodiment of the invention, the plate is generally a T-shaped volar plate defining an elongate body, a head portion angled relative to the body, a first side which is intended to contact the bone, and a second side opposite the first side. The body portion includes a plurality of countersunk screw holes for the extension of the bone screws therethrough. The head portion includes a plurality of threaded peg holes for receiving the pegs therethrough. The pegs are angularly adjustable relative to the peg holes and can be independently fixed in selectable orientations; i.e., the pegs are multidirectional.[0011]
• To stabilize a Colles' fracture, the volar plate is positioned with its first side against the volar side of the radius and bone screws are inserted through the bone screw holes into the radius to secure the volar plate to the radius. The bone fragments are then aligned and, through the peg holes, holes are drilled into and between the bone fragment at angles chosen by the surgeon. The pegs are then inserted into the peg holes and into the drilled holes, and a set screw (or screw cap) is inserted over each peg to lock the peg in the volar plate at the chosen orientation. The volar fixation system thereby stabilizes and secures the bone fragments in their proper orientation.[0012]
• The various adjustably directable pegs can also be used in conjunction with fracture fixation plates adapted for fractures of other bones, e.g., the proximal and distal humerus, the proximal and distal ulna, the proximal and distal tibia, and the proximal and distal femur.[0013]
• Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.[0014]
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is an illustration of an extremity subject to a Colles' fracture;[0015]
• FIG. 2 is a top volar view of a right hand volar fixation system according to a first embodiment of the invention;[0016]
• FIG. 3 is a side view of a volar plate according to the first embodiment of the volar fixation system of the invention;[0017]
• FIG. 4 is a section view of the head portion of the volar fixation system according to the invention;[0018]
• FIG. 5 is a proximal perspective view of a bone peg according to an embodiment of the invention;[0019]
• FIGS. 6 and 7 are proximal and distal perspective views, respectively, of a set screw according to the a first embodiment of the invention;[0020]
• FIG. 8 is a broken section view of a first embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0021]
• FIG. 9 is a broken perspective view of a peg and set screw according to the first embodiment of the directable peg assembly of the invention;[0022]
• FIG. 10 is an illustration of the first embodiment of the volar fixation system provided in situ aligning and stabilizing a Colles' fracture;[0023]
• FIG. 11 is a broken section view of a second embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0024]
• FIG. 12 is a broken perspective view of a peg and set screw according to the second embodiment of the directable peg assembly for a fracture fixation system according to the invention;[0025]
• FIG. 13 is a broken section view of a third embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0026]
• FIG. 14 is a broken perspective view of a peg and set screw according to the third embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0027]
• FIG. 15 is a broken section view of a fourth embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0028]
• FIG. 16 is a broken perspective view of a peg and set screw according to the fourth embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0029]
• FIG. 17 is a broken section view of a fifth embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0030]
• FIG. 18 is a broken perspective view of a peg and set screw according to the fifth embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0031]
• FIG. 19 is a broken section view of a sixth embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0032]
• FIG. 20 is a broken perspective view of a peg and set screw according to the sixth embodiment of a directable peg assembly for a fracture fixation system according to the invention;[0033]
• FIG. 21 is a broken section view of a seventh embodiment of directable peg assembly for a fracture fixation system according to the invention;[0034]
• FIG. 22 is a broken perspective view of a peg and set screw according to the seventh embodiment of a directable peg assembly of the invention;[0035]
• FIG. 23 is a broken section view of an eighth embodiment of directable peg assembly for a fracture fixation system according to the invention;[0036]
• FIG. 24 is a broken exploded perspective view of a peg and set screw according to the eighth embodiment of a directable peg assembly of the invention;[0037]
• FIG. 25 is a broken section view of a ninth embodiment of directable peg assembly for a fracture fixation system according to the invention, shown with a driver for the peg; and[0038]
• FIG. 26 is a broken perspective view of a peg, set screw and driver according to the ninth embodiment of a directable peg assembly of the invention.[0039]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• Turning now to FIGS. 2 through 4, a first embodiment of a[0040]fracture fixation system100 is particularly adapted for aligning and stabilizing multiple bone fragments in a Colles' fracture. Thesystem100 generally includes a substantially rigid T-shapedplate102 intended to be positioned against the volar side of the radial bone, a plurality of preferably self-tappingbone screws104 for securing theplate102 along a non-fractured portion of the radial bone, and a plurality of bone pegs108 which extend from theplate102 and into bone fragments of a Colles' fracture.
• The T-shaped[0041]plate102 defines ahead portion116, anelongate body portion118 angled relative to the head portion, afirst side120 which is intended to contact the bone, and asecond side122 opposite the first side. Thefirst side120 at the head portion is preferably planar, as is the first side at the body portion. As the head portion and body portion are angled relative to each other, the first side preferably defines two planar portions. The angle Ø between thehead portion116 and thebody portion118 is preferably approximately 23° and bent at a radius of approximately 0.781 inch. Thedistal edge121 of thehead portion116 is preferably angled proximally toward the medial side at an angle α, e.g.5′, relative to a line P, which is perpendicular to the body portion. Theplate102 preferably has a thickness of approximately 0.1 inch, and is preferably made from a titanium alloy, such as Ti-6A-4V.
• The[0042]body portion118 includes four preferably countersunk screw holes124,126,127,128 for the extension of thebone screws104 therethrough. One of the screw holes,128, is preferably generally elliptical (or oval).
• The[0043]head portion116 includes fourpeg holes130, preferably closely spaced (e.g., within 0.25 inch of each other) and arranged along a line or a curve, for individually receiving thepegs108 therethrough.
• According to the invention, each peg can be directed through a range of angles within a respective peg hole and fixed at a desired angle within the range. Referring to FIGS. 4 and 8, according to a first embodiment of the invention, each[0044]peg hole130 in thevolar plate102 includes a cylindrical upper bore140 provided withthreads146 and alower portion148 having a radius of curvature. Thelower end154 of each peg hole includes acircumferential bevel156.
• Referring to FIGS. 4, 5 and[0045]8, eachpeg108 includes ahead160 and acylindrical shaft162. Theproximal portion164 of thehead160 includes acup167 having an outer radius R_Osubstantially corresponding to the radius of thelower portion148 of the peg holes130, and a relatively smaller inner radius R_iof curvature. Thehead160 defines preferably approximately 160° of a sphere. Theshaft162 includes aslight taper166 at the intersection with thehead160, and a roundeddistal end168. According to a preferred manufacture of the first embodiment, thecylindrical shaft162 of eachpeg108 is first provided with a sphere (not shown) or a hemisphere (not shown) at a proximal end. If a sphere is provided, it is cut to a hemisphere. The hemisphere is then hollowed and further reduced to the 160° shape. Finally, thetaper166 is provided at the intersection.
• Referring to FIGS. 5 and 8, the[0046]surface150 of thelower portion148 of thepeg hole130 and/or theouter surface152 of thehead160 of thepeg108 is preferably roughened, e.g., by electrical, mechanical, or chemical abrasion, or by the application of a coating or material having a high coefficient of friction.
• Turning now to FIGS. 6 through 9, each[0047]set screw110 includes aproximal hex socket170,circumferential threads172 adapted to engage thethreads146 of the upper bore140 of the peg hole, and distal substantiallyhemispherical portion174 having substantially the same radius of curvature as the inner radius of curvature R_iof thecup167, and preferably substantially smaller than a radius of the peg holes130.
• Referring to FIGS. 4 and 10, to stabilize a Colles' fracture, the[0048]plate102 is positioned on theradius10, and at least one hole is drilled through the elliptical screw hole on the volar plate and into theradius10. Then, one or more bone screws104 are inserted through the plate and into the bone. The fracturedbones16,18,20 are then adjusted under theplate102 into their desired stabilized positions, and the bone screws104 are tightened. Then, through the peg holes130, the surgeon drills holes into the fracture location for the stabilization pegs108. The holes may be drilled at any angle within a predefined range, and preferably at any angle within a range of 15° relative to an axis normal A_Nto the lower surface of the head of the volar plate. Each hole may be drilled at the same angle or at relatively different angles. After each hole is drilled, apeg108 is inserted therein. Referring back to FIG. 8, thebevel156 at thelower end154 of thepeg hole130 and thetaper166 on the shaft cooperate to permit the peg to be oriented with greater freedom relative to the axis A_N, if required, as interference between the peg hole and peg shaft is thereby reduced. Once thepeg108 has been appropriately positioned within the peg hole, one of theset screws110 is threaded into the upper bore140 of thepeg hole130. Thehemispherical portion174 contacts thehead160 of the peg, seating in the concavity of thecup167. As theset screw110 is tightened, thesurface152 of the head of the peg, which may be roughened, is clamped between theset screw110 and the roughenedinner surface150 of the lower portion of thepeg hole130, thereby securing the peg in the selected orientation. The other pegs are similarly positioned and angularly fixed.
• Turning now to FIGS. 11 and 12, a second embodiment of a directable peg assembly for a fracture fixation plate is shown. The[0049]plate202 includes threaded peg holes230 that are generally larger in diameter than thehead260 of thepegs208 intended for use therethrough. This permits a hole to be drilled through thepeg hole230 at a relatively greater angle than with respect toholes130. Thelower end248 of thepeg hole230 is constricted relative to the upper threadedportion249. Thepeg208 includes a spherically-curved head260, acylindrical shaft262, and an optionally constrictedneck266 therebetween. Theset screw210 includes asquare opening270 adapted to receive a square driver,threads246 about its circumference, and a substantially sphericallycurved socket274 adapted to receive thehead260 of thepeg208. As seen in FIG. 12, the lower portion of theset screw210 includesexpansion slots276 which permit the lower portion of theset screw210 to temporarily deform to receive thehead260 of the peg208 (which has a diameter greater than theopening278 of the spherical socket); i.e., thehead260 can be snapped into thesocket274.
• In use, for each[0050]peg hole230 and peg208, holes are drilled through the peg holes and into the bone along axes at which it is desired to have pegs extend for stabilization of the fracture fragments. Thehead260 of thepeg208 is snapped into theopening278 of thesocket274. Theshaft262 of thepeg208 is then inserted into a respective bone hole until theset screw210 meets thepeg hole230. It is appreciated that theset screw210 can be rotated relative to thepeg208, as thesocket274 andspherical head260 form a ball and socket coupling. As such, theset screw210 is rotatably secured in thepeg hole230 to secure thepeg208 at the desired angle within the drilled hole.
• Turning now to FIGS. 13 and 14, a third embodiment of a directable peg assembly for a fracture fixation plate is shown. The[0051]plate302 includes threaded peg holes330 that preferably have a stepped diameter, with a relativelylarge countersink portion380 adapted to receive the head of aset screw310, a threadedcentral portion382, and a relatively smallerlower portion384. Thepeg308 includes a substantially spherically-curved head360 having a central square opening386 adapted to receive a driver, and a threadedcylindrical shaft362. Theset screw310 includes a head portion388 having a square opening370 for also receiving a driver, a threadedportion390, and a lower spherically-curved socket374.
• In use, for each[0052]peg hole330 and peg308, a hole is drilled through a respective peg hole and into the bone at the angle at which it is desired to receive a peg for stabilization of the fracture. Thepeg308 is then positioned within thepeg hole330 and rotatably driven into the bone with a driver (not shown). Once thepeg308 is fully seated against thelower portion384 of thepeg hole330, theset screw310 is threaded into thecentral portion390 of the peg hole and urged against thehead360 of thepeg308 to clamp the peg in position. The head portion388 of theset screw310 preferably at least partially enters thecountersink portion380 of the peg hole to provide a lower profile to the assembly.
• Turning now to FIGS. 15 and 16, a fourth embodiment of a directable peg assembly for a fracture fixation plate is shown. The[0053]plate402 includes threaded peg holes430 each with alower portion448 having a radius of curvature, and alower end454 provided with a preferablycircumferential bevel456. Thepeg408 includes a sphericallycurved head460 defining asocket467 extending in excess of 180°, acylindrical shaft462, and an optionallytapered neck466 therebetween. Thehead460 about thesocket467 is provided withexpansion slots476. Theset screw410 includes anupper portion488 having asquare opening470 for a driver, andthreads490, and alower ball portion474 adapted in size an curvature to snap into thesocket467.
• In use, for each[0054]peg hole430 and peg408, holes are drilled through the peg hole and into the bone at the angles at which it is desired to receive pegs for stabilization of fragments of the fracture. Theball portion474 of theset screw410 is snapped into thesocket467, with thesocket467 able to expand to accept theball portion474 by provision of theexpansion slots476. Theshaft462 of thepeg408 is then inserted into a respective bone hole until theset screw410 meets thepeg hole430. It is appreciated that theset screw410 can rotate relative to thepeg408, as theball portion474 andsocket467 are rotatably coupled to each other. As such, theset screw410 is then rotatably secured in thepeg hole430 to secure thepeg408 in the bone.
• Turning now to FIGS. 17 and 18, a fifth embodiment of a directable peg assembly for a fracture fixation plate, substantially similar to the fourth embodiment, is shown. In the fifth embodiment, the[0055]head560 of thepeg508 includes two sets ofpin slots594a,594bdefining two planes P₁and P₂oriented transverse to each other. In addition, thehead560 includesradial expansion slots576. Theball portion574 of theset screw510 includes twopins598a,598bextending through a center thereof and oriented transverse to each other. Theball portion574 is snapped into thesocket567 defined by thehead560 of thepeg508, and pins598a,598bare positioned through thepin slots594a,594bto rotatably lock the peg and set screw together, yet permit thepeg508 to articulate relative to theset screw510. The fifth embodiment is suitable for rotatably inserting threadedpegs508 into a bone hole via rotation of theset screw510, and may be used in a similar manner to the fourth embodiment.
• Turning now to FIGS. 19 and 20, a sixth embodiment of a directable peg assembly for a fracture fixation plate is shown. The assembly includes a[0056]peg608 having a substantially sphericallycurved head660 provided with four nubs680 (two shown) arranged in 90° intervals about the periphery of thehead660. Theset screw610 includeslower walls682 defining asocket674 for thehead660. In addition, thewalls682 defineslots684 through which thenubs680 can move.
• In use, the assembly of the[0057]peg608 with itsset screw610 functions substantially similar to a universal joint. Thepeg608 is then inserted through arespective peg hole630 and into a drilled hole in a bone untilthreads690 on theset screw610 engagemating threads692 in the peg hole. Theset screw610 is then rotated, which causes rotation of thepeg608 within the drilled hole. When theset screw610 is fully seated in thepeg hole630, thepeg608 is secured in the bone.
• Turning now to FIGS. 21 and 22, a seventh embodiment of a directable peg assembly for a fracture fixation plate is shown. The peg holes[0058]730 in theplate702 each include a threaded cylindricalupper portion746 and a spherically-curvedlower portion748 having a smaller hole diameter than the upper portion. Eachpeg708 has ahead760 with a lower relatively larger sphericallycurved portion762 and an upper relatively smaller sphericallycurved portion764, and ashaft766. The lowercurved portion762 preferably spherically curves through substantially 150°, while the uppercurved portion764 preferably spherically curves through substantially 210°. The peg shaft is optionally provided withthreads769, and when so provided, the lowercurved portion762 of the peg is provided withdriver notches768. Theset screw710 includes anupper portion788 having aslot770 or other structure for engagement by a driver,threads790, and alower socket792.
• In use, for each[0059]peg708, a hole is drilled through a respective peg hole into the bone at an orientation desirable for receiving that particular peg for stabilization of the fracture. Apeg708 is then inserted through thepeg hole730 and into the drilled hole until the curvedlower surface762 of thehead760 of the peg seats against the curvedlower portion748 of the peg hole. If the peg hasthreads769, a driver (not shown) may be coupled to thepeg708 at thenotches768 to rotationally drive the peg into the drilled hole. Theset screw710 is then threaded into thepeg hole730 until thesocket792 extends over theupper portion764 of thehead760 of the peg and presses thereagainst to force thelower portion762 of the head against spherically-curvedlower portion748 of thepeg hole730 to clamp thepeg708 in position. In the seventh embodiment, thesocket792 of theset screw710 does not necessarily capture (i.e., extend more than 1800 about) any portion of thehead760 of thepeg708. However, thesocket792 may be modified to enable such capture.
• Turning now to FIGS. 23 and 24, an eighth embodiment of a directable peg assembly for a fracture fixation plate is shown. The peg holes[0060]830 of the plate each include a spherically-curved portion848 preferably having a roughened relatively high friction surface. Eachpeg808 has a substantially spherically-curved head860 provided with a preferably roughenedouter surface861, an upper threadedaxial bore863, and a plurality ofradial slots865 extending between the outer surface and the bore. Theset screw810 includes anupper slot870 for adapted to receive a driver andtapered threads890.
• In use, for each[0061]peg808, a hole is drilled through a respective peg hole into the bone at an orientation desirable for receiving that particular peg for stabilization of the fracture. Apeg808 is then inserted through thepeg hole830 and into the drilled hole. When thepeg808 is fully seated in thepeg hole830 and at the desired angle, theset screw810 in threadably inserted into thebore863. Theset screw810 has a diameter slightly larger than thebore863. As such, as thescrew810 is inserted, thehead860 of thepeg808 is enlarged at theslots865 to accommodate thescrew810, and the high friction surfaces861,848 are forced against each other thereby locking thepeg808 in thepeg hole830 at its chosen axial orientation.
• Turning now to FIGS. 25 and 26, a ninth embodiment of a directable peg assembly for a fracture fixation plate is shown. The peg holes[0062]930 and threadedpegs908 are substantially similar to the peg holes330 and pegs308 of the third embodiment (FIGS. 13 and 14). It is noted that the lower end of thepeg hole930 has a lowercurving taper931. Also according to the ninth embodiment, theset screw910 includes acentral hole969, anupper slot970 extending across thehole969,helical threads990, alower socket992, and a plurality ofcompression slots994 about the socket.
• In use, for each[0063]peg908, a hole is drilled through arespective peg hole930 into the bone at an orientation desirable for receiving that particular peg for stabilization of the fracture. Adriver1000 having ashaft1001 provided with a distalmostsquare end1002 and relativelyproximal flanges1004 is then used for the assembly. The threadedpeg908 is positioned at the entry of the bone hole, and theset screw910 is positioned thereover, with thesocket992 of the set screw resting on thehead960 of the peg. Thesquare end1002 of the driver is then inserted through thehole969 and into asquare opening986 at thehead960 of the peg, and theflanges1004 of thedriver1000 are inserted into theupper slot970. Thedriver1000 is rotated to threadably insert thepeg908 into the bone hole. When theset screw910 meets thepeg hole930, it is also threaded therein with the driver, and when alower portion911 of the set screw contacts thecurving taper931 of the peg hole, the set screw is compressed about thecompression slots994 to secure thepeg908 in position.
• There have been described and illustrated herein several embodiments of a volar fixation system, as well as directable peg systems suitable for numerous applications related to the fixation of various bone fractures. In each of the embodiments, the head of a peg is clamped between a portion of the fixation plate and a set screw, preferably with the head of the peg and fixation plate thereabout being treated to have, or having as material properties, high friction surfaces. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Thus, while particular materials for the elements of the system have been disclosed, it will be appreciated that other materials may be used as well. In addition, fewer or more peg holes and bone pegs may be used, preferably such that at least two pegs angled in two dimensions relative to each other are provided. Also, while a right-handed volar plate is described with respect to an embodiment of the invention, it will be appreciated that right- or left-handed model, with such alternate models being mirror images of the models described. In addition, while it is disclosed that the pegs may be directed through a range of 150, the peg holes and pegs may be modified to permit a greater, e.g. up to 300, or smaller, e.g. 50, range of such angular direction. Furthermore, while several drivers for applying rotational force to set screws and pegs have been disclosed, it will be appreciated that other rotational engagement means, e.g., a Phillips, slotted, star, multi-pin, or other configuration may be used. Also, the plate and pegs may be provided in different sizes adapted for implant into different size people. Furthermore, while four screw holes are described, it is understood that another number of screw holes may be provided in the plate, and that the screw holes may be located at positions other than shown. In addition, individual aspects from each of the embodiments may be combined with one or more aspects of the other embodiments. Moreover, while some elements have been described with respect to the mathematically defined shapes to which they correspond (e.g., spherical), it is appreciated that such elements need only correspond to such shapes within the tolerances required to permit the elements to adequately function together; i.e., the elements need only be “substantially” spherical in curvature. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as claimed.[0064]

Claims (16)

1. A fracture fixation system, comprising:

a) a substantially rigid plate having a plurality of peg holes adapted to individually receive fixation pegs therein, said peg holes having an upper portion and a lower portion, said upper portion having a first internal thread, and said lower portion having a radius of curvature;

b) a plurality of pegs each having a head and a shaft, said shaft sized to be received through said peg holes, and said head having a lower surface with substantially a same radius of curvature as said lower portion of said peg holes; and

c) a plurality of set screws each having a body including a second thread rotationally engageable with said first thread, and a proximal rotational engagement means for permitting a rotational force to be applied to said set screw,

wherein when said pegs are provided into respective peg holes, each said peg may be positioned at a plurality of angles relative to an axis normal to a lower surface of a portion of said plate surrounding a respective peg hole, and once so positioned, respective set screws when threaded into said upper portions of said peg holes fix said pegs at their respective angles.

2. A fracture fixation system according toclaim 1, wherein:

when said pegs are fixed at their respective angles, said pegs are adapted to provide a framework for supporting fractured bone fragments, said pegs of said framework defining a plurality of non-parallel axes.

3. A fracture fixation system according toclaim 1, wherein:

said peg holes are closely spaced in a linear or curvilinear arrangement.

4. A fracture fixation system according toclaim 1, wherein:

said fixation plate has a body portion and a head portion angled relative said body portion.

5. A fracture fixation system according toclaim 4, wherein:

said body portion and said head portion are configured in a T-shape.

6. A fracture fixation system according toclaim 1, wherein:

said body portion includes at least one non-threaded screw hole.

7. A fracture fixation system according toclaim 1, wherein:

said lower portion of said peg hole has a spherical radius of curvature.

8. A fracture fixation system according toclaim 1, wherein:

said lower portion of each of said peg holes defines a surface having a relatively high coefficient of friction.

9. A fracture fixation system according toclaim 1, wherein:

said outer surface of said head of each of said pegs has a surface having a relatively high coefficient of friction.

10. A fracture fixation system according toclaim 1, wherein:

said plurality of angles is any angle within a predefined range of angles.

11.-30 (canceled)

31. A fracture fixation system, comprising:

a) a substantially rigid T-shaped plate having a body portion and a head portion angled relative to said body portion, said head portion defining a plurality of peg holes adapted to individually receive fixation pegs therein;

b) a plurality of pegs each having a head portion and a shaft portion, said shaft portion sized to be received through said peg holes, and said head portion defining a ball portion having an outer surface and a substantially spherical radius of curvature, an axial threaded bore, and at least one radial slot extending from said outer surface into said threaded bore; and

c) a plurality of set screws each having a body including a outer thread sized to be rotationally engageable with said threaded bore of said head portion of said peg but causing said ball portion to increase in diameter as said set screw is rotated therein, and a proximal rotational engagement means for permitting a rotational force to be applied to said set screw,

wherein when said pegs are provided into respective peg holes, each said peg may be positioned at a plurality of angles relative to an axis normal to a lower surface of said plate, and once so positioned, respective set screws when threaded into said upper bores of said head portions of said pegs expand said head portions at said respective at least one slot and clamp said head portions between said set screws and said plate and thereby fix said pegs at their respective angles.

32. A fracture fixation system according toclaim 31, wherein:

said peg holes are each provided with substantially a same substantially spherical radius of curvature as said ball portion of each said peg.

33. A fracture fixation system according toclaim 31, wherein:

said peg holes are non-threaded.

34.-35. (canceled)

36. A fracture fixation system according toclaim 1, wherein:

said shaft of at least one of said pegs is non-threaded.

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