Bone connector system with anti-rotational feature

• US 6,458,134 B1
• Filed: 06/23/2000
• Issued: 10/01/2002
• Est. Priority Date: 08/17/1999
• Status: Expired due to Term

• Current Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Original Assignee: Pioneer Laboratories Incorporated
• Inventors: Songer, Matthew N., Kilpela, Thomas S., Korhonen, Francis J., Berrevoets, Greg A.
• Primary Examiner(s): Lucchesi, Nicholas D.
• Assistant Examiner(s): Priddy, Michael B.
• Application Number:
  US09/602,771
• Time in Patent Office: 830 Days
• Field of Search: 606/53, 606/60, 606/65, 606/66, 606/72, 606/73
• US Class Current: 606/304
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61B 17/72 Intramedullary pins, nails or other devices A61B17/744 takes precedence
• CPC Class Codes: A61B 17/7291 for small bones, e.g. in the foot, ankle, hand or wrist
• CPC Class Codes: A61B 17/864 hollow, e.g. with socket or cannulated
• CPC Class Codes: A61B 17/8685 comprising multiple separate parts

Abstract

A bone connector system comprises first and second connector members. At least one, and preferably both, of the connector members carries an external bone screw thread to permit securance within a bone. One of the connector members defines a boss having an outer end with intersecting slots therein to form flexible fingers, the boss having flanges which may be formed by an external screw thread adjacent to the outer end and an external hexagonal engagement surface spaced from the outer end. The other of the connector members defines a bore having grooves which may be formed by an internal screw thread proportioned to engage the flanges on the boss, and a hexagonal engagement portion proportioned to mateably receive and engage the hexagonal engagement surface, when the connectors are brought together. Either or both of the connector members may define guidewire lumens.

Claims

1. A bone connector system comprising:

first and second connector members;

at least one of said connector members having an external bone screw thread to permit attachment within a bone;

one of the connector members having a bore therein having an outer end;

the bore having an engagement portion of non-circular peripheral shape adjacent to the outer end;

the other of the connector members having a boss dimensioned to be received in the bore;

the boss having an outer engagement surface of non-circular peripheral shape disposed for mating engagement with the first engagement portion when the boss is received in the bore; and

coupling structure interconnecting the first and second members to inhibit removal of the boss from the bore, wherein the coupling structure includes a first portion on the one member and a second portion on the other member, the first portion includes internal peripheral grooves in the bore inboard of the engagement portion, the second portion including external peripheral flanges on the boss adjacent to the distal end thereof and disposed for engagement in the grooves when the boss is received in the bore, and the grooves are formed by an internal helical thread and the flanges are formed by an external helical thread.

2. A bone connector system comprising:

first and second connector members;

at least one of said connector members having an external bone screw thread to permit attachment within a bone;

one of the connector members having a bore therein having an outer end;

the bore having a first engagement portion of non-circular peripheral shape adjacent to the outer end;

the bore having a second engagement portion with internal peripheral grooves disposed inboard of the first engagement portion;

the other of the connector members having a boss dimensioned to be received in the bore;

the boss having a distal end with a slot extending transversely through the boss at the distal end;

the boss having an outer engagement surface of non-circular peripheral shape disposed for mating engagement with the first engagement portion when the boss is received in the bore; and

the boss having external peripheral flanges adjacent to the distal end disposed for engagement in the grooves when the boss is received in the bore, wherein the grooves are formed by an internal helical thread and the flanges are formed by an external helical thread.

3. A bone connector system comprising:

first and second connector members;

at least one of said connector members having an external bone screw thread to permit attachment within a bone;

one of the connector members having a bore therein having an outer end;

the bore having a first engagement portion of non-circular peripheral shape adjacent to the outer end;

the bore having a second engagement portion with internal peripheral grooves disposed inboard of the first engagement portion;

the other of the connector members having a boss dimensioned to be received in the bore;

the boss having a distal end with a slot extending transversely through the boss at the distal end;

the boss having an outer engagement surface of non-circular peripheral shape disposed for mating engagement with the first engagement portion when the boss is received in the bore; and

the boss having external peripheral flanges adjacent to the distal end disposed for engagement in the grooves when the boss is received in the bore, wherein the grooves are greater in number than the flanges.

4. A bone connector system comprising:

first and second connector members;

at least one of said connector members having an external bone screw thread to permit attachment within a bone;

one of the connector members having a bore therein having an outer end;

the bore having a first engagement portion of non-circular peripheral shape adjacent to the outer end;

the bore having a second engagement portion with internal peripheral grooves disposed inboard of the first engagement portion;

the other of the connector members having a boss dimensioned to be received in the bore;

the boss having a distal end with a slot extending transversely through the boss at the distal end;

the boss having an outer engagement surface of non-circular peripheral shape disposed for mating engagement with the first engagement portion when the boss is received in the bore; and

the boss having external peripheral flanges adjacent to the distal end disposed for engagement in the grooves when the boss is received in the bore, wherein at least one of the connector members has a lumen extending therethrough.

5. The system of claim 4, wherein both of the connector members have lumens extending therethrough.

6. A bone connector system comprising:

first and second connector members;

at least one of said connector members having an external bone screw thread to permit attachment within a bone;

one of the connector members having a bore therein having an outer end,

the bore having an engagement portion of non-circular peripheral shape adjacent to the outer end,

the other of the connector members having a boss dimensioned to be received in the bore; and

the boss having an outer engagement surface of non-circular peripheral shape disposed for mating engagement with the first engagement portion when the boss is received in the bore, wherein at least one of the connector members has a lumen extending therethrough.

7. The system of claim 6, wherein both of the connector members have lumens extending therethrough.

8. A bone connector system for approximating bone surfaces of small bone portions in substantially fixed position relative to each other, the bone connector system comprising:

female and male connector members each having an axis and a predetermined length therealong sized for being implanted in the small bone portions;

external bone screw threads along the length of the connector members to allow the connector members to be implanted in the respective bone portions including the bone surfaces to be approximated;

an axial bore of the female connector member having an open end thereof;

an attachment portion of the male connector member sized to be received in the axial bore and extending for a predetermined portion length along the length of the male connector member;

at least one radial projection and at least one recess wherein the projection is associated with one of the male connector member attachment portion and the female connector member bore and the recess is associated with the other of the male connector member and female connector member bore to provide a snap-fit attachment between the implanted connector members for keeping the bone surfaces approximated;

cooperating engagement surfaces in the female connector member bore and on the male connector member attachment portion, each extending axially for a predetermined surface length along the respective lengths of the connector members and having other than circular configurations; and

predetermined positions of the engagement surface and the radial projection or recess along the attachment portion of the male connector member so that with the projection received in the recess to snap-fit the connector members together, the engagement surfaces will be in overlapping relation for a predetermined overlap distance along the predetermined axial surface lengths thereof sufficient to inhibit relative rotation between the implanted connector members.

9. The bone connector system of claim 8 wherein the attachment portion includes a generally cylindrical wall and the at least one radial projection and at least one recess comprise external threads on the cylindrical wall and internal threads in the female connector bore;

and

a predetermined axial spacing between the predetermined positions of the external threads and the male connector engagement surface of sufficient length to allow the external threads to resiliently cam past the internal threads with axial insertion of the attachment portion into the bore to be non-rotatably received therein.

10. The bone connector system of claim 9 wherein the cylindrical wall includes an axial slot in the wall that extends along the axial spacing for increasing flexibility of the wall for snap-fitting of the threads to each other and keeping wall length to a minimum.

11. The bone connector system of claim 8 wherein the at least one radial projection and at least one recess comprise a plurality of annular projections and a plurality of annular grooves, and the attachment portion has a split construction along the projections to provide sufficient resiliency to the attachment portion for camming the projections into mating engagement with the grooves with axial insertion of the attachment portion into the bore.

12. The bone connector system of claim 11 wherein the projections and grooves comprise external and internal helical threads, respectively.

13. The bone connector system of claim 8 wherein the connector members include stop surfaces extending transverse to the respective axes thereof and positioned relative to each other so that with the stop surfaces in abutting relation, the predetermined overlap distance corresponds to the predetermined surface length of the engagement surface in the female connector member bore to maximize resistance to relative rotation between the connector members.

14. The bone connector system of claim 13 wherein the connector members each have a drive head including drive surfaces and the transverse stop surfaces with the drive head of the male connector member being larger than the drive head of female connector member so that the stop surface on the male connector member drive head abuts the stop surface on the female connector drive head.

15. The bone connector system of claim 8 wherein the configurations of the engagement surfaces are polygonal, and the female connector member has a drive head adjacent the open end of the bore and including an external polygonal drive surface for turning of the female connector member about the axis thereof for threading into a bone portion with the female connector polygonal engagement surface being an internal surface of the drive head.

16. The bone connector system of claim 15 wherein the polygonal engagement surfaces each comprise hex surfaces sized for a close mating fit therebetween.

17. The bone connector system of claim 8 wherein the attachment portion has a stepped configuration to provide a larger and smaller sections thereof and a transverse shoulder surface therebetween with the predetermined position of the engagement surface being on the larger section and the predetermined position of the radial projection or recess being on the smaller section.

18. The bone connector system of claim 17 wherein the male connector member has a drive head adjacent the attachment portion larger section and enlarged in a radial direction relative thereto to form another transverse shoulder surface disposed between the enlarged drive head and the attachment portion.

19. The bone connector system of claim 18 wherein the at least one radial projection and the at least one recess comprise external threads on the attachment portion and internal threads in the bore including a thread closest to the bore opening positioned to engage the shoulder surface between the attachment portion sections to stop axial insertion of the attachment portion into the bore with the threads snap-fit together.

20. The bone connector system of claim 19 wherein the transverse shoulder surface between the drive head and attachment portion is positioned to abut the female connector member about the open end of the bore with the shoulder surface between the attachment portion sections abutting the stop thread.

21. The bone connector system of claim 8 wherein the at least one radial projection and at least one recess comprise a plurality of projections and recesses on the male connector member and in the female connector member bore, respectively, and the predetermined positions allow the connector members to be non-rotatably snap-fit together at a plurality of different axial positions with respect to each other via the plurality of projections and recesses.

22. The bone connector system of claim 11 wherein the overlap distance between the engagement surfaces increases as the connector members are snap-fit together at successive ones of the different axial positions.