Conversion of hip fusion to Charnley low-friction arthroplasty.

Spontaneous fusion of the hip following infection or surgical procedures can result in deformity that causes degenerative change in the associated joints. Loss of function can cause pain in adjacent joints. Conversion of hips fused in a deformed position to low-friction arthroplasty reduces shearing strain and improves walking function. Conversion of the fused hips constitutes a technically difficult procedure; adequate exposure with trochanteric osteotomy with the patient in the supine position is strongly advocated.