CLAVICULAR BONE PLATE

Abstract

A bone plate (1) for positioning along a medial or lateral portion of a clavicle including an upper surface (2) which, in an operative position, faces away from the clavicle, a lower surface (3) which, in the operative position, faces toward the clavicle, a non-linear central longitudinal axis (4), a middle portion (5) of the length L.sub.M, a left terminal portion (6) of the length L.sub.L extending from the left end of the middle portion having a plurality of circular screw holes (8) for receiving bone screws, and a right terminal portion (7) of the length L.sub.R extending from the right end of the middle portion having a plurality of circular screw holes (9) for receiving bone screws. The total length L of the bone plate corresponds to L=L.sub.M+L.sub.L+L.sub.R, and at least one of the circular screw holes is a variable angle screw hole.

Claims

1: A bone plate for positioning along a medial or lateral portion of a shaft of a clavicle bone, the bone plate comprising: (i) an upper surface which, in an operative position, faces away from the clavicle bone; (ii) a lower surface which, in the operative position, faces toward the clavicle bone; (iii) a non-linear central longitudinal axis; (iv) a middle portion having a length L.sub.M; (v) a left terminal portion having a length L.sub.L extending from a left end of the middle portion, said left terminal portion having a plurality of first circular screw holes for receiving bone screws; (vi) a right terminal portion of the length L.sub.R extending from a right end of the middle portion and having a plurality of second circular screw holes for receiving bone screws; wherein (vii) a total length L of the bone plate corresponds to L=L.sub.M+L.sub.L+L.sub.R; and (viii) at least one of the first or second circular screw holes is a variable angle screw hole configured to receive a bone screw at a user-selected angle.

2: The bone plate according to claim 1, wherein the middle portion is free of screw holes.

3: The bone plate according to claim 1, wherein the left terminal portion is curved in one direction and has a number x of first circular screw holes, and wherein the right terminal portion is curved in an opposite direction to the curvature of the left terminal portion and has a number y of second circular screw holes, where y<x.

4: The bone plate according to claim 1, wherein centers of the first and second circular screw holes are arranged along the non-linear central longitudinal axis.

5: The bone plate according to claim 1, wherein the bone plate as seen in a lateral view thereof is curved.

6: The bone plate according to claim 1, wherein the length L.sub.M of the middle portion measures at least 0.15 L.

7: The bone plate according to claim 1, wherein the length L.sub.L of the left terminal portion measures at least 0.35 L.

8: The bone plate according to claim 1, wherein the length L.sub.R of the right terminal portion measures at least 0.3 L.

9: The bone plate according to claim 3, wherein the curved left terminal portion has a radius of curvature in the range of 50 mm-80 mm.

10: The bone plate according to claim 3, wherein the curved right terminal portion has a radius of curvature in the range of 85 mm-115 mm.

11: The bone plate according to claim 1, wherein the width of the left terminal portion increases from the middle portion to a free end of the left terminal portion.

12: The bone plate according to claim 1, wherein the left terminal portion has a number x of the first circular screw holes which is at least twice as much as a number y of the second circular screw holes of the right terminal portion.

13: The bone plate according to claim 1, wherein the middle portion comprises at least one suture hole extending transverse to the non-linear central longitudinal axis for receiving a suture.

14: The bone plate according to claim 1, wherein at least one of the first or second circular screw holes is a variable angle screw hole that is configured to receive a bone screw at an angle of ±15° with regard to a central axis of the variable angle screw hole.

15: The bone plate according to claim 1, wherein at least one of the first or second circular screw holes has an inner wall made of a material which has a hardness H.sub.P, wherein a hollow cylinder-shaped or hollow cone-shaped insert is mounted in said at least one of the first or second circular screw holes such that said insert at least partially abuts the inner wall, wherein the insert is configured to accommodate a head of a bone screw, wherein the insert is arranged in said at least one of the first or second circular screw holes such that it is secured against rotation, and wherein the insert consists of a material that has a hardness H.sub.E<H.sub.P.

16: The bone plate according to claim 1, wherein the non-linear central longitudinal axis is essentially straight in the middle portion.

17: The bone plate according to claim 1, wherein at least one of the left or right terminal portions is provided with a long hole.

18: The bone plate according to claim 1, wherein the bone plate comprises at least one bending zone having a reduced width between two adjacent first or second circular screw holes.

19: The bone plate according to claim 1, wherein the bone plate comprises at least one K-wire hole of lesser diameter compared to the diameter of the circular screw holes.

20: A bone plate that is a mirror image version of a bone plate according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Several embodiments of the invention will be described in the following by way of example and with reference to the accompanying drawings in which:

[0043] FIG. 1 illustrates a perspective view of a special embodiment of a midshaft clavicle bone plate according to the invention;

[0044] FIG. 2 illustrates a top view of the clavicle plate according to FIG. 1;

[0045] FIG. 3 illustrates a lateral view of the clavicle plate according to FIG. 1;

[0046] FIG. 4 illustrates a perspective side view of the clavicle plate according to FIG. 1;

[0047] FIG. 5 illustrates a perspective view of another embodiment of a midshaft clavicle bone plate according to the invention;

[0048] FIG. 6 illustrates a top view of the clavicle plate according to FIG. 5;

[0049] FIG. 7 illustrates a lateral view of the clavicle plate according to FIG. 5;

[0050] FIG. 8 illustrates a perspective side view of the clavicle plate according to FIG. 5;

[0051] FIG. 9 illustrates a perspective view of an embodiment of a lateral clavicle bone plate according to the invention;

[0052] FIG. 10 illustrates a top view of the clavicle plate according to FIG. 9;

[0053] FIG. 11 illustrates a lateral view of the clavicle plate according to FIG. 9;

[0054] FIG. 12 illustrates a perspective side view of the clavicle plate according to FIG. 9;

[0055] FIG. 13 illustrates a perspective view of another embodiment of a lateral clavicle bone plate according to the invention;

[0056] FIG. 14 illustrates a top view of the clavicle plate according to FIG. 13;

[0057] FIG. 15 illustrates a lateral view of the clavicle plate according to FIG. 13; and

[0058] FIG. 16 illustrates a perspective side view of the clavicle plate according to FIG. 13.

DETAILED DESCRIPTION OF THE INVENTION

[0059] FIGS. 1 to 4 illustrate a first embodiment of a midshaft clavicle bone plate 1 according to the invention. The bone plate 1 has an upper surface 2 which, in an operative position, faces away from the clavicle bone and a lower surface 3 which, in the operative position, faces toward the clavicle bone. The bone plate 1 has a longitudinal axis 4 which basically has an S-shape. The middle portion 5 of the length L.sub.M of the bone plate is essentially straight. A left terminal portion 6 of the length L.sub.L extends from the left end of the middle portion 5 and has four first circular screw holes 8 for receiving bone screws.

[0060] A right terminal portion 7 of the length L.sub.R extends from the right end of the middle portion 5 and has three second circular screw holes 9 for receiving bone screws.

[0061] The left terminal portion 6 is curved in one direction and the right terminal portion 7 is curved in an opposite direction to the curvature of the left terminal portion 6 so that the longitudinal axis 4 basically has an S-shape.

[0062] The total length L of the bone plate 1 therefore corresponds to L=L.sub.M+L.sub.L L.sub.R.

[0063] All of the seven of the first and second circular screw holes 8;9 are variable angle screw holes which allow to receive a bone screw at a user-selected angle and are arranged along the central longitudinal axis 4.

[0064] The variable angle screw holes 8;9 allow to receive a bone screw at an angle of ±15° with regard to the central axis of the screw hole. The screw holes 8;9 have an inner wall made of a material which has a hardness H.sub.P. A hollow cylinder-shaped or hollow cone-shaped insert is mounted in each screw hole, which at least partially abuts the inner wall and is suitable for accommodating the head of a bone screw. The insert is arranged in the screw hole such that it is secured against rotation. The insert consists of a material that has a hardness H.sub.E<H.sub.P.

[0065] Between individual first and/or second circular screw holes (8;9) there are bending zones 13 with a reduced plate width allowing to adapt the shape of the bone plate 1 more easily.

[0066] The lower surface 3 of the bone plate 1—as seen in a cross-section orthogonal to the central longitudinal axis 4—is cylindrically concave, whereas the upper surface 2—as seen in a cross-section orthogonal to the central longitudinal axis 4—is cylindrically convex. The cross-section of the bone plate 1 orthogonal to its central longitudinal axis 4 tapers in a trapezoidal shape in the direction of the lower surface 3.

[0067] The free ends of the left terminal portion 6 and of the right terminal portion 7 are beveled and comprise each a Kirschner wire hole 11 which is parallel to the first circular screw holes 8, and the second circular screw holes 9, respectively. This allows to define an optimal screw alignment, for fixing the plate to the bone, the fracture to be reduced and held and also to guarantee the reposition of the bone fracture.

[0068] FIGS. 5 to 8 illustrate a second embodiment of a midshaft clavicle bone plate 1 according to the invention. With respect to the first embodiment according to FIGS. 1-4 the following modifications are present. The left terminal portion 6 as well as the right terminal portion 7 are both provided with a long hole 10 allowing interfragmentary compression in both directions of the longitudinal axis 4 where needed. Furthermore, the plate 1 is provided with four K-wire holes 11 for receiving Kirschner wires.

[0069] The long hole 10 in the left and right terminal portions 6;7 are positioned between the most central first circular screw hole 8 and second most central first circular screw hole 8. Two of the K-wire holes are positioned at the left and the right end of the plate 1 and the two other K-wire holes are positioned centrally of the second last first circular screw holes.

[0070] FIGS. 9 to 12 illustrate a first embodiment of a lateral clavicle bone plate 1 according to the invention. Compared to the two embodiments of the midshaft clavicular plates according to FIGS. 1-4 and 5-8 the left terminal portion 6 of the bone plate 1 is enlarged towards the left end and is provided with a larger number (six) of first circular screw holes 8. A K-wire hole 11 is provided at the beveled free end of the right terminal portion 7.

[0071] A single long hole 10 is positioned in the right terminal portion 7 and the middle portion 5 is provided with a suture hole 12 extending transverse to the longitudinal axis 4 for receiving a suture allowing a suture cerclage of the clavicle plate. The surgeon can make a suture cerclage with the suture hole 12. For example, a suture anchor can be screwed into the coracoid and then the sutures are looped through the suture hole and then tightened with a knot so that the position of the clavicle can be secured.

[0072] FIGS. 13 to 16 illustrate a second embodiment of a lateral clavicle bone plate 1 according to the invention. It is basically similar to the first embodiment according to FIG. 9-12 with the exception of the right terminal portion 7 which is longer and provided with four first circular screw holes 8 (instead of only two).

Fracture Reduction and Temporary Plate Fixation

[0073] Restoration of normal length, axis and rotation remains the fundamental principle for fracture reduction in shaft fractures. After exposing the clavicle, the two fragments may have to be distracted to restore the length. The properly chosen plate may be placed on the clavicle to assist in temporary fixation. A reduction forceps may be used to allow for proper reduction; furthermore, large fragments may also be reduced and held temporarily in place with bone clamps or Kirschner wires. A usual plate holding and reduction clamp for the clavicle may be used to facilitate temporary fixation with the plate in place. Kirschner wire holes available at the lateral and medial ends of the clavicle bone plate according to the invention further assist with temporary maintenance of the reduction.

[0074] The clavicle bone plate may be used as internal fixator to allow for bridging osteosynthesis. Only the main fragments are being reduced while the comminuted fracture zone is left without screws to allow for indirect fracture healing.

[0075] For very lateral Neer Type IIB clavicle fractures, indirect fixation of the fracture with suture fixation (through the specific suture hole(s) provided in the lateral clavicle bone plate according to the embodiment of FIGS. 9-12 and 13-16 reduce the coraco-clavicular dehiscence and allow for healing.

[0076] Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the scope of the appended claims.

[0077] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination or as suitable in any other described embodiment of the invention. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.