Abstract
The hypothesis of the current study was that the loading of the proximal femur is altered significantly by the surgical approach. The change in long-term periprosthetic bone mineral density in relation to the alteration of the musculature after the anterolateral (Group A) and transgluteal approaches (Group B) has been compared. Group A comprised 35 hip joints (30 patients) and Group B 47 hip joints (37 patients). No significant differences were seen between groups in respect to age, gender, or diaphyseal BMD distribution and in respect to average stem size in a Wilcoxon test. Measurement of BMD in femoral Gruen Zones I, II, VI, and VII revealed a significant bone loss in Group B compared with Group A; however the functional outcome showed no significant differences between the two groups postoperatively. Analysis of proximal femoral loading by means of a validated musculoskeletal model showed a considerable redistribution of the musculoskeletal loading across the hip during walking and stair climbing after a transgluteal compared with an anterolateral surgical approach. The muscular damage caused by the surgical approach seems to have a significant influence on the long-term bone loss and the initial postoperative loading of the proximal femur.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
