Abstract
A mild degree of femoral deformity can be accommodated in total hip replacement by using a small, cemented stem, but this results in abnormal mechanics and potentially early failure. Minor degrees of rotatory and angular deformity proximal to the lesser trochanter can be handled by a custom or modular implant, which will allow changes in version and offset. Deformities below the lesser trochanter should be corrected by osteotomy. This is true of rotational and angular deformity. Where there is a leg length problem, a shortening osteotomy can be carried out at the subtrochanteric region.
To achieve angular stability after osteotomy, full canal fill over 5 cm or more is preferable. The rotational stability can be achieved by step cuts, side plates, etc. If the implant is distally fluted with thin, sharp flutes and if it is capable of giving proximal rotational control then simple horizontal butt joint osteotomy is all that is required. The osteotomy should be carried out at the summit of the deformity and proximal and distal prophylactic cerclage wiring is advised.
If the gluteal muscles are weak as they may be in a high DDH case, a subtrochanteric osteotomy will allow leg length balancing, correction of proximal anteversion, and if the proximal fragment is retrograde reamed exiting through the neck cut rather than the periform fossa, lateralisation to increase the gluteal power can be achieved.
The abstracts were prepared by Mrs Dorothy L. Granchi, Course Coordinator. Correspondence should be addressed to her at PMB 295, 8000 Plaza Boulevard, Mentor, Ohio 44060, USA.
