Endoprosthesis shaft
US4535487A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1984 |
| Grant date | Aug 20, 1985 |
| Priority date | — |
| Expiry date | Jan 13, 2004 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F2230/0034
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.