Patent ID: 7462180

Claim:
An insertion instrument for a flexible prosthetic acetabular cup, the acetabular cup having a part-spherical outer shell and an inner bearing element with the shell and inner bearing element having at least one opening therein extending from an open end of the shell and bearing element toward a polar area of the shell comprising the opening having a curved periphery: a shaft having a mounting element for contacting the open end of the shell at a first end of said shaft; a retractable rod element connected to at least one engagement element for resiliently engaging side walls of the opening in the shell and bearing element, the engagement element having curved outer periphery and edges for engaging the curved periphery of the outer shell and bearing element sidewalls, the engagement element having a width greater than a non-expanded width of the opening in a direction parallel to a circumference of the open end and the edges of the engagement element are chamfered; and a retractor mounted adjacent a second end of the shaft for moving said engagement element on said rod out of engagement with the sidewalls of the shell while maintaining the mounting element in engagement with the open shell end.