Compression pin with opposed threaded regions

Abstract

A compression pin (10) for urging two bone regions (12A) (12B) together includes a pin body (14) having a distal end (220), an opposed proximal end (222), a first threaded region (216), and a second threaded region (218). The first threaded region (216) is positioned near the distal end (220), and the second threaded region (218) is positioned near the first threaded region (216). The first threaded region (216) includes a first thread (228) having a FT leading surface (242F) that is at a FT leading angle (248F), and the second threaded region (218) includes a second thread (230) having a ST leading surface (242S) that is at a ST leading angle (248S) that is different than the FT leading angle (248F). Additionally, the first thread (228) includes a FT trailing surface (244F) that is at a FT trailing angle (246F), and the second thread (230) includes a ST trailing surface (244S) that is at a ST trailing angle (246S) that is different than the FT trailing angle (246F). Moreover, the first thread (228) has a first thread shape and the second thread (230) has a second thread shape that is substantially opposite to the second thread shape. With this design, during insertion of the compression pin (10), the first threaded region (216) and the second threaded region (218) cooperate to aggressively compress the bone regions (12A) (12B) together.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:

FIG. 1 is a simplified side illustration of a pair of bone regions, in cut-away, that are fused together with a compression pin having features of the present invention;

FIG. 2A is a side view of a first embodiment of a compression pin having features of the present invention;

FIG. 2B is an enlarged detail view taken from FIG. 2A;

FIG. 2C is an enlarged detail view taken from FIG. 2B;

FIG. 2D is an end view of the compression pin of FIG. 2A;

FIG. 2E is a cut-away view taken on line 2E-2E in FIG. 2D;

FIG. 2F is an enlarged detail view taken from FIG. 2E;

FIG. 2G is an enlarged detail view taken from FIG. 2E;

FIG. 3A is a side view of a second embodiment of a compression pin having features of the present invention;

FIG. 3B is an enlarged detail view taken from FIG. 3A;

FIG. 3C is an end view of the compression pin of FIG. 3A;

FIG. 3D is a cut-away view taken on line 3D-3D in FIG. 3C;

FIG. 3E is an enlarged detail view taken from FIG. 3D;

FIG. 3F is an enlarged detail view taken from FIG. 3D;

FIG. 4A is a side view of a third embodiment of a compression pin having features of the present invention;

FIG. 4B is an enlarged detail view taken from FIG. 4A;

FIG. 4C is an end view of the compression pin of FIG. 4A;

FIG. 4D is a cut-away view taken on line 4D-4D in FIG. 4C;

FIG. 4E is an enlarged detail view taken from FIG. 4D; and

FIG. 4F is an enlarged detail view taken from FIG. 4D.

Claims

1. A compression pin for urging two bone regions together, the compression pin comprising: a pin body having a distal end, an opposed proximal end, a first threaded region positioned near the distal end, and a second threaded region positioned near the first threaded region, the first threaded region including a first thread having a FT leading surface that is at a FT leading angle, and the second threaded region including a second thread having a ST leading surface that is at a ST leading angle that is at least approximately two degrees different than the FT leading angle.

2. The compression pin of claim 1 wherein the ST leading angle is at least approximately ten degrees different than the FT leading angle.

3. The compression pin of claim 1 wherein the ST leading angle is at least approximately twenty degrees different than the FT leading angle.

4. The compression pin of claim 1 wherein ST leading angle is at least approximately twenty-five degrees different than the FT leading angle.

5. The compression pin of claim 1 wherein the ST leading angle is approximately two degrees and the FT leading angle is approximately thirty degrees.

6. The compression pin of claim 1 wherein the first thread has a FT trailing surface that is at a FT trailing angle, and the second thread has a ST trailing surface that is at a ST trailing angle that is at least approximately two degrees different than the FT trailing angle.

7. The compression pin of claim 6 wherein the ST trailing angle is at least approximately ten degrees different than the FT trailing angle.

8. The compression pin of claim 6 wherein the ST trailing angle is at least approximately twenty degrees different than the FT trailing angle.

9. The compression pin of claim 6 wherein the ST trailing angle is at least approximately twenty-eight degrees different than the FT trailing angle.

10. The compression pin of claim 6 wherein the ST trailing angle is approximately thirty degrees and the FT trailing angle is approximately two degrees.

11. The compression pin of claim 1 wherein the first thread has a FT root width, and the second thread has a ST root width that is at least approximately two percent different than the FT root width.

12. The compression pin of claim 1 wherein the first thread has a FT root width, and the second thread has a ST root width that is at least approximately two percent different than the FT root width.

13. The compression pin of claim 1 wherein the first thread has a first thread cross-sectional shape and the second thread has a second thread cross-sectional shape and wherein the first thread cross-sectional shape is approximately opposite to the second thread cross-sectional shape.

14. A compression pin for urging two bone regions together, the compression pin comprising: a pin body having a distal end, an opposed proximal end, a first threaded region positioned near the distal end, and a second threaded region positioned near the first threaded region, the first threaded region including a first thread having a FT trailing surface that is at a FT trailing angle, and the second threaded region including a second thread having a ST trailing surface that is at a ST trailing angle that is at least approximately two degrees different than the FT trailing angle.

15. The compression pin of claim 14 wherein the ST trailing angle is at least approximately ten degrees different than the FT trailing angle.

16. The compression pin of claim 14 wherein the ST trailing angle is at least approximately twenty degrees different than the FT trailing angle.

17. The compression pin of claim 14 wherein the ST trailing angle is at least approximately twenty-eight degrees different than the FT trailing angle.

18. The compression pin of claim 14 wherein the ST trailing angle is approximately thirty degrees and the FT trailing angle is approximately two degrees.

19. The compression pin of claim 14 wherein the first thread has a first thread cross-sectional shape and the second thread has a second thread cross-sectional shape and wherein the first thread cross-sectional shape is approximately opposite to the second thread cross-sectional shape.

20. A compression pin for urging two bone regions together, the compression pin comprising: a pin body having a distal end, an opposed proximal end, a first threaded region positioned near the distal end, and a second threaded region positioned near the first threaded region, the first threaded region including a first thread having a first thread cross-sectional shape, and the second threaded region including a second thread having a second thread cross-sectional shape that is approximately opposite to the first thread cross-sectional shape.

21. The compression pin of claim 20 wherein the first thread has a FT leading surface that is at a FT leading angle, and the second thread has a ST leading surface that is at a ST leading angle that is at least approximately two degrees different than the FT leading angle.

22. The compression pin of claim 21 wherein the first thread has a FT trailing surface that is at a FT trailing angle, and the second thread has a ST trailing surface that is at a ST trailing angle that is at least approximately two degrees different than the FT trailing angle.