Between October 1986 and November 1987, 208 total hip arthroplasties were
performed with use of the cementless Zweymüller stem and a threaded cup
in 200 consecutive patients. Of 102 patients (108 hips) who were available for
follow-up at a minimum of 180 months postoperatively, eighty-three
(eighty-nine hips) had the primary joint replacement still intact. No stem had
been revised because of aseptic loosening, but we found various degrees of
osteolysis around sixteen (18%) of the implants. The probability of survival
of the stem at fifteen years was 0.98 (95% confidence interval, 0.96 to 1.00).
The probability of survival of the cup was 0.85 (95% confidence interval, 0.79
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.