Constrained orthopaedic implants and methods of repair

Inventors

Zubizarreta, Joel • Guederian, Gregory

Assignees

Arthrex Inc

Abstract

This disclosure relates to orthopaedic implants and methods for restoring functionality to a bone and/or joint. The implants disclosed herein may be dimensioned and/or positioned relative to a bone to establish a constraint. The implants may include an articular surface establishing the constraint. The articular surface may have different radii of curvature to establish a non-spherical contour.

Core Innovation

The invention relates to an orthopaedic implant for shoulder arthroplasty having an implant body extending along a central axis between a front face and a rear face, where the rear face is dimensioned to abut bone and an anchor member extends outwardly from the rear face to secure the implant body to bone. The front face includes a concave articular surface dimensioned to mate with an opposed convex articular surface of an implant or bone.

The concave articular surface includes first and second non-spherical contours extending across a length and across a width of the front face, respectively, and the first non-spherical contour is defined between first and second lips that establish a perimeter of the implant body. A trough of the first contour is established between the central axis and the second lip, and the radius of curvature of the first contour decreases from the trough towards the first lip.

A second non-spherical contour extends across a width of the front face at the trough, and the radius of curvature of the second contour decreases from the trough towards a perimeter of the articular surface. The geometry further defines a maximum depth position of the articular surface at the trough and a tangent line relative to the first contour at the trough, wherein the tangent line is inclined toward the first lip and is transverse to the central axis.

In further embodiments, the first contour extends along a reference plane that intersects the first and second lips, and the central axis extends along the reference plane. A perimeter of the articular surface between the first and second lips projected onto the reference plane establishes an arcuate peripheral contour with ends joined with respective ends of the first contour, and a trough of the peripheral contour is established between, but spaced apart from, the first lip and the trough of the first contour.

Claims Coverage

The independent claims provide an orthopaedic shoulder arthroplasty implant and implant kits defined by a bone-abutting rear face with an outward anchor member, and a front-face concave articular surface with non-spherical contours characterized by lips, a trough, curvature that decreases from the trough toward the lips/perimeter, and constraint-defining tangent/reference-plane geometry. Across the independent claims, the main inventive features are concentrated into about six core geometric and structural aspects.

Across the independent claims, the claim coverage is directed to shoulder arthroplasty implants and kits that combine a bone-abutting rear face with an outward anchor member and a concave articular surface having non-spherical contours defined by lips and a trough, with radii of curvature decreasing from the trough toward the lips/perimeter. Additional independent-claim coverage defines a maximum depth at the trough, a tangent line at the trough inclined toward the lip and transverse to the central axis, and in some embodiments reference-plane-based arcuate peripheral contouring with a peripheral trough spaced apart from the first lip and the trough of the first contour. Kit claims also add pairing with a convex humeral implant and a superior constraint to limit superior movement.

Stated Advantages

Documented Applications