Radial head prosthesis with floating articular member

• US 9,155,626 B2
• Filed: 09/10/2013
• Issued: 10/13/2015
• Est. Priority Date: 09/10/2012
• Status: Active Grant

• Current Assignee: Acumed Llc (Berkshire Hathaway Incorporated)
• Original Assignee: Acumed Llc (Berkshire Hathaway Incorporated)
• Inventors: Huebner, Randall J., Bergquist, Jeff Andrew, Budor, Kara J., Ehmke, Larry W.
• Primary Examiner(s): Willse, David H
• Assistant Examiner(s): BLANCO, JAVIER G
• Application Number:
  US14/023,179
• Publication Number:
  US 20140074246A1
• Time in Patent Office: 763 Days
• Field of Search: 623/20.11, 623 11- 2013, 623/23.42
• US Class Current: 1/1
• CPC Class Codes: A61F 2/3804 for elbows
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30362 with possibility of relative movement between the protrusion and the recess
• CPC Class Codes: A61F 2002/30364 Rotation about the common longitudinal axis
• CPC Class Codes: A61F 2002/30369 Limited lateral translation of the protrusion within a larger recess
• CPC Class Codes: A61F 2002/30378 Spherically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30563 having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30571 Leaf springs
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/3809 for radio-humeral joints
• CPC Class Codes: A61F 2002/3818 for proximal radio-ulnar joints, i.e. PRU joints
• CPC Class Codes: A61F 2002/3827 Radial components

Abstract

System, including apparatus, methods, and kits, for replacement of the proximal end of a radial bone with a prosthesis having a floating articular member. The prosthesis may include a head portion connected or connectable to a stem portion. While the stem portion remains operatively connected to the head portion, the head portion and/or an articular member thereof may be permitted to float in position relative to the stem portion. The head portion/articular member may float transversely (e.g., translationally) and/or rotationally with respect to the stem portion. The articular member may articulate with a humeral bone or both a humeral bone and an ulnar bone. In some embodiments, the head portion may include a fixed member for articulation with an ulnar bone and a floating member for articulation with a humeral bone.

Claims

1. A method of replacing an end of a radial bone with a radial head prosthesis having a stem portion and a head portion, the head portion connected or connectable to the stem portion, the head portion comprising a fixed member and a floating articular member, the method comprising:

operatively installing the prosthesis such that the stem portion of the prosthesis is attached to a radial bone, the fixed member directly articulates with an ulnar bone, and the floating articular member directly articulates with a humeral bone and is operatively movable translationally with respect to the fixed member in a direction transverse to a long axis defined by the radial bone when the radial head prosthesis is finally implanted and fully operational,

wherein the fixed member includes a cup portion, and wherein the floating articular member is disposed in the cup portion after the step of installing.

2. The method of claim 1, wherein at least one of the ulnar bone and the humeral bone includes a prosthetic region, and wherein at least one of the fixed member and the floating member articulates at least in part with a prosthetic region.

3. The method of claim 1, wherein a majority by volume of the floating member is disposed in the cup portion after the step of installing.

4. The method of claim 1, wherein the floating member is rotatable with respect to the fixed member during movement of the radial bone with respect to the ulnar bone and/or humeral bone after the step of operatively installing.

5. The method of claim 1, wherein wherein the head portion includes at least one resilient member that is deformable to bias a position of the floating member with respect to the fixed member.

6. A method of replacing a proximal end of a radial bone with a radial head prosthesis having a stem portion and a head portion, the head portion connected or connectable to the stem portion, the method comprising:

installing the prosthesis in an operative configuration, with the stem portion mounted to a radial bone, a first member of the head portion directly articulating with an ulnar bone and fixed with respect to the stem portion, and a second member of the head portion directly articulating with a humeral bone and operatively movable translationally with respect to the first member in a direction transverse to a long axis defined by the stem portion when the radial head prosthesis is finally implanted and fully operational,

wherein the second member is a floating articular member,

wherein the first member includes a cup portion, and wherein the floating articular member is disposed in the cup portion after the step of installing.

7. The method of claim 6, wherein the second member is rotatable with respect to the first member in the operative configuration.

8. The method of claim 6, wherein at least one of the ulnar bone and the humeral bone includes a prosthetic region, and wherein at least one of the first member and the second member articulates at least in part with said prosthetic region.

9. The method of claim 6, wherein the second member is connected to the first member by a movable joint that permits translational motion and rotational motion of the first and second members relative to each other.

10. The method of claim 6, wherein the second member is connected to the stem portion by a slidable joint and a pivotable joint that are distinct from each other.

11. The method of claim 6, wherein the step of installing permits the floating articular member to rotate as a unit with respect to the stem portion to change a tilt of the floating articular member with respect to the stem portion.

12. The method of claim 6, wherein the floating articular member is operatively connected to the stem portion by a movable joint including a spherical surface region corresponding to no more than one-half of a complete sphere.