10 Jahre zementfreie Implantation von Hüfttotalendoprothesen unter Verwendung des Zweymüller-Schaftes

Abstract

A retrospective study of the first consecutive 111 cementless Zweymüller Stems has been performed. 56 cases have been followed clinically and radiologically with an interval of 10-11 years. The average harris hip score was 90.7 pts, the cumulative success rate of the stem was 97.96% after 10-11 years. The frequency of bony reactions around the stem and their changes during the course of time could be followed in 40 implants with a complete radiologic documentation at 5 and 10 years postoperative. Hypertrophic changes of the bone around the tip of the stem remained unchanged from the fifth to the tenth year but there was an increase of proximal lucencies (27% at 5 yrs, 35 at 10 yrs), widening of the calcar (20% at 5 yrs, 25% at 10 yrs) and stress shielding (30% at 5 yrs, 47% at 10 yrs).

High 10-Year Survival Rate with an Anatomic Cementless Stem (SPS)

“…The rate of patients with thigh pain was low in our cohort, comparing well with the lower rates of thigh pain reported in the literature for uncemented stems, which, although not always reported in studies, varies from 0% to 17% [1, 25, 35, 39]. Naumann et al [31] reported 29% of patients had thigh pain during the first months after surgery and 5.6% had pain remaining afterward, for the first generation of the Zweymüller stem.…”

“…However, an incidence of thigh pain of 5.7% to 17% was reported with the early designs [25, 35, 39] contrasting with the absence of pain reported by Flecher et al [13, 14] with the anatomic custom stems. Therefore an anatomic cementless stem was designed, based on a computerized three-dimensional (3-D) analysis of a 300 CT scan database, which allowed defining an average metaphyseal femoral shape.…”

“…However, the lack of stability and fixation could be assessed clinically with the presence of thigh pain. Despite high survival rates, thigh pain has varied from 0% to 17% in patients [1, 25, 35, 39]. Many factors contributed to the long-term fixation and stability of the SPS stem.…”

Performance of the Zweymüller total hip arthroplasty system: a literature review including arthroplasty register data

“…As to the first generation of the Zweymüller system, four publications fulfilled the inclusion criteria [1][2][3][4]. Two studies [3,4] dealt with the whole system (cup and stem); the stem [1] and the cup [2] alone were treated in one study each.…”

“…Two studies [3,4] dealt with the whole system (cup and stem); the stem [1] and the cup [2] alone were treated in one study each.…”