摘要 |
The load P on an artificial hip joint produces a bending moment on the endoprosthesis shaft composed of a shaft proper (1), a collar (2) fitting the resection plane and a cone (3) for carrying the femur ball (14). The extra load B thereby provided on the medial side of the femur is relieved by providing means for resisting the tension force A of the bending moment by providing the shaft with cavities (11) separated by ribs (12) as well as by a median longitudinal rib (broken lines).The bone grows into the cavities thus securing the area against the tension effects. Additional cavities (9) and wedge-shaped nubs (7) and (5) similarly oppose forces A and/or B. Hollows (10) on the underside of the collar (2), as well as the cavities (11) and (9), also oppose twisting forces.
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