| 摘要 |
Wrist joint prosthesis. As a replacement for the joint in a human wrist, there is provided a prosthesis permitting both vertical motion, sidewise motion and rotary motion but preventing twisting motion around an axis projecting from and parallel with the lower forearm. For this purpose, there is provided a metal socket fitted with a prong receivable into a bone of the forearm. A plastic cup made of material self-lubricating with respect to such metal socket is fitted within said socket, snappable thereinto to resist but not prevent withdrawal therefrom and having a rectangular projection-and-slot relationship with said metal socket to permit relative motion with respect thereto in only a single plane. A metal ball is receivable into the recess of said plastic cup, snappable therewith to resist but not prevent withdrawal therefrom and has a rectangular projection-and-slot relationship with the inside of said plastic cup to permit relative movement with respect thereto in only a single plane, said plane being substantially perpendicular to said first-named plane. Suitable projections are provided on said ball for reception into the bones of selected fingers, normally the index and middle finger. Placement of said prosthesis in one position or a mirror image thereof will render said prosthesis without other change adaptable for use with one hand or the other hand as desired. |
