Intramedullary bone fixation device for ribs

Patent metadata

Field	Value
Publication number	US-11844553-B2
Application number	US-202217931141-A
Country	US
Kind code	B2
Filing date	Sep 12, 2022
Priority date	Sep 13, 2021
Publication date	Dec 19, 2023
Grant date	Dec 19, 2023

Abstract

An intramedullary bone fixation device that includes a shaft with a flexible region. The flexible region may be configured to flex from a first shape to a second shape as the shaft moves along a curved medullary canal. For example, the bone fixation device may include a distal bone screw that is configured to move along the curved medullary canal of first and second segments of a fractured bone (e.g., two segments of a broken rib) and fasten to the segment bone segment. The bone fixation device may include a locking member (e.g., a proximal bone screw) that is configured to lock the shaft to the first bone segment. For example, the shaft may be fixed to the distal bone screw and ratchetably coupled to the shaft such that the first and second bone segments can be compressed together by urging together the distal bone screw and the locking member.

First claim

What is claimed:

1. An intramedullary bone fixation device comprising:
a shaft having a leading end and a trailing end opposite the leading end;
a bone screw that extends from the leading end of the shaft, wherein the bone screw is configured to move along a curved medullary canal of a bone; and
a locking member that includes at least one ratcheting arm that includes at least one protrusion that is configured, when in a locked position, to engage the shaft such that the locking member is movable along the shaft toward the leading end and is not movable along the shaft toward the trailing end,
wherein the shaft has a flexible region between the leading end and the trailing end, and the flexible region is configured to flex from a first shape to a second shape as the bone screw moves along the curved medullary canal.

2. The intramedullary bone fixation device of claim 1 , wherein the shaft is configured to transmit torque from the trailing end to the bone screw via the flexible region.

3. The intramedullary bone fixation device of claim 1 , wherein the flexible region includes a plurality of laser cut segments that interlock with one another.

4. The intramedullary bone fixation device of claim 1 , wherein when in an unlocked position, the locking member is configured to move along the shaft toward the trailing end and is configured to move along the shaft toward the leading end.

5. The intramedullary bone fixation device of claim 1 , wherein the locking member includes radially outer helical threading.

6. The intramedullary bone fixation device of claim 1 , wherein the at least one protrusion is at least two radially inwardly extending protrusions configured to engage the shaft when the locking member is in the locked position.

7. The intramedullary bone fixation device of claim 6 , wherein the at least two radially inwardly extending protrusions are movable to disengage from the shaft such that the locking member is in an unlocked position, where the locking member is movable toward the trailing end and is movable toward the leading end.

8. The intramedullary bone fixation device of claim 7 , wherein the at least one ratcheting arm is a pair of ratcheting arms that each include a respective radially inwardly extending protrusion of the at least two radially inwardly extending protrusions, and wherein the respective radially inwardly extending protrusions are disposed at a distal end of the respective ratcheting arm.

9. The intramedullary bone fixation device of claim 1 , wherein the bone screw is configured to ream and purchase with cancellous bone.

10. The intramedullary bone fixation device of claim 1 , wherein the flexible region comprises a plurality of segments, and adjacent segments define recesses therebetween, wherein the at least one protrusion is configured to be disposed within least one of the recesses when in the locked position.

11. The intramedullary bone fixation device of claim 1 , wherein the flexible region comprises a plurality of segments that are each configured such that adjacent segments are pivotable relative to one another and are inseparable from one another.

12. A method of securing first and second bone segments together, the method comprising the steps of:
driving a leading end of a bone fixation device through a first portion of a curved medullary canal that is defined by the first bone segment, and into a second portion of the curved medullary canal that is defined by the second bone segment;
causing a shaft, of the bone fixation device, with a flexible region to flex from a first shape to a second shape during the driving step;
fixing the leading end to the second bone segment; and
moving a locking member along the shaft toward the leading end, wherein the locking member includes at least one ratcheting arm that includes at least one protrusion that is in a locked position such that the at least one protrusion engages the shaft, and the locking member is not movable along the shaft toward a trailing end of the shaft that is opposite the leading end.

13. The method of claim 12 , further comprising urging the first bone segment toward the second bone segment.

14. The method of claim 13 , wherein the locking member urges the first bone segment toward the second bone segment.

15. The method of claim 12 , further comprising unlocking the locking member, by moving the at least one protrusion away from the shaft, and moving the locking member away from the leading end along the shaft.

16. The method of claim 15 , further comprising moving the locking member within the first portion of the curved medullary canal along the shaft toward the leading end.

17. The method of claim 12 , wherein driving the leading end into the first portion comprises inserting an intramedullary bone screw defining the leading end into the first portion.

18. The method of claim 17 , further including reaming the first and second portions with the bone screw and purchasing the bone screw with cancellous bone defining the second portion of the curved medullary canal.

19. The method of claim 12 , further comprising inserting a resorbable or non-resorbable adhesive or polymer into the shaft such that the adhesive or polymer secures the shaft to the first and second bone segments.

20. The method of claim 19 , wherein the adhesive or polymer is a cyanoacrylate, calcium phosphate, or poly (L/DL-lactide).

Assignees

• Depuy Synthes Products Inc

Inventors

• Noon John M
• Keegan Christopher
• Peta Christian
• Montello Albert

Classifications

• A61B17/7208 Primary

  Flexible pins, e.g. ENDER pins · CPC title

• A61B17/1693

  for the ribs · CPC title

• A61B17/7258

  with laterally expanding parts, e.g. for gripping the bone · CPC title

• A61B2017/00004

  (bio)absorbable, (bio)resorbable or resorptive · CPC title

• A61B2017/00407

  Ratchet means · CPC title