摘要 |
An acetabular implant of a hip joint prosthesis comprising a metal cup shell (2) having an external self-tapping thread extending around the circumference of the shell. The thread is divided into a plurality of segments (8, 10) by a plurality of tapping grooves (16). The thread radius (Ra, Rb, Rc, Rd) of the thread segments (8, 10) progressively decreases from the leading end (12) to the trailing end (14) of a segment (8 or 10). The tapping grooves (16) are preferably arranged in pairs dividing the thread into alternating long (8) and short (10) segments. The construction of the thread reduces the propensity of the implant to jam during insertion.
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