| 摘要 |
A ball-and-socket joint prosthesis, e.g. a hip joint prosthesis, which comprises an outer shell element (34), a ball component (42), and a replaceable bearing insert element (10) positioned between the shell and the ball component. The bearing insert has a generally spherical inside surface which encompasses more than half of the ball component to thereby retain it. The insert has an outside surface (12) shaped to mate with the inside surface of the shell (35), and the shell element and the insert element have a locking mechanism consisting of a protruding portion (18) which extends a major distance around a side surface (142) of one element which locks into a mating depression (38) in the other element. In a preferred embodiment, the insert is horizontally slotted (16) around a major portion, but less than the entire distance around the insert, above that portion of the locking mechanism present on the insert and is vertically slotted (26) from the bottom of the insert to the horizontal slot thereby forming at least one, but preferably two, movable finger(s) (20, 20'). The flexibility of the finger(s) allows the ball component to be inserted into and removed from the insert. Once the insert containing the ball component is locked into the shell, the vertical slot may be at least partially closed by moving the finger(s) to disengage the locking mechanism and allow removal of the insert and the ball component from the shell. |
