Spherical joint for hip joint prosthesis - includes cup shaped half with tapered metal shell carrying cutting thread formed by saw teeth

摘要

The cup shaped half (1) of a hip joint prosthesis has a part conical metal shell (2) containing a core (7) with a half spherical recess (4) for the ball end of the other half. The sloping external surface of the shell includes a helical thread (10) formed by short sawtoothed sections, which may be of briar tooth type. The clearance angle of each tooth is between 5 and 15 degrees and the cutting angle is less than 15 degrees. ADVANTAGE - Strong connection with the pelvis.