US 5,702,469 A · Thumb joint prosthesis and related method of implantation

Abstract

A trapezium-metacarpal thumb joint prosthesis having a metacarpal component for insertion into a metacarpal bone of a human thumb and a trapezium component for insertion into a trapezium bone of a human thumb. The metacarpal component has a forward end of generally truncated hemispherical shape with a convex surface and a rear end having a base and a stem. The trapezium component has a forward end of a generally cylindrical shape with a concave surface with a radially built up shoulder and a rear end having a base and a stem. The concave surface is adapted for non-captive rotational abutment with the convex surface. Also, a related method for implantation of the prosthesis into the metacarpal and trapezium bones of a human thumb, wherein the two components are respectively inserted into a pre-cut void in each of the respective bones from a direction above the radial side of the thumb substantially transverse to the longitudinal axis of each respective bone of the thumb.

Claims10

Dependent claims

A trapezio-metacarpal thumb joint prosthesis adapted for implantation into a metacarpal bone and a trapezium bone of a trapezio-metacarpal thumb joint a human thumb, the thumb having a radial side and the metacarpal and trapezium bones each having a longitudinal axis, said prosthesis comprising:

(a) a metacarpal component having (i) a forward end of a generally truncated hemispherical shape and having a convex surface, and (ii) a rear end having a stem, and the stem being adapted for insertion into a pre-cut void in a pre-selected thumb metacarpal bone from a direction above the radial side of the thumb substantially transverse to the longitudinal axis of the metacarpal bone;
and
(b) a trapezium component having (i) a forward end of a generally cylindrical shape and having a generally concave surface, the concave surface being adapted for non-captive rotational abutment with the convex surface of the metacarpal component, and (ii) a rear end having a stem, and the stem being adapted for insertion into a pre-cut void in a pre-selected thumb trapezium bone from a direction above the radial side of the thumb substantially transverse to the longitudinal axis of the trapezium bone.

A method for implantation of a trapezio-metacarpal thumb joint prosthesis into a trapezium bone and a metacarpal bone of a trapezio-metacarpal thumb joint of a human thumb, the thumb having a radial side and the metacarpal and trapezium bones each having a longitudinal axis, said method comprising:

(a) providing a hand having a pre-selected thumb metacarpal bone and a pre-selected thumb trapezium bone;
(b) cutting a void in the metacarpal bone and a void in the trapezium bone;
(c) implanting a trapezio-metacarpal thumb joint prosthesis comprising:
(I) a metacarpal component having
(i) a forward end of a generally truncated hemispherical shape and having a convex surface, and
(ii) a rear end having a stem, and
(II) a trapezium component having (i) a forward end of a generally cylindrical shape and having a concave surface, the concave surface being adapted for non-captive rotational abutment with the convex surface of the metacarpal component, and (ii) a rear end having a base and a stem,
by inserting the stem of the metacarpal component into the void in the metacarpal bone from a direction above the radial side of the thumb substantially transverse to the longitudinal axis of the metacarpal bone and the stem of the trapezium component into the void in the trapezium bone from a direction above the radial side of the thumb substantially transverse to the longitudinal axis of the trapezium bone;
and
(d) placing the convex surface of the metacarpal component against the concave surface of the trapezium component.

7 more elements

Dependencies are inferred from the claim text.

Thumb joint prosthesis and related method of implantation

Life of this patent

Thumb joint prosthesis and related method of implantation

Life of this patent

Abstract

Claims10