[Arthroplasty of the hip using a double cup].

In this double-cup arthroplasty, only the acetabular cup is sealed with cement; the femoral cup is simply implanted into the femoral head and neck. This operation was performed on 67 hips. Complications were limited to one hip dislocation, one break in cemented seal with ossification, one isolated massive ossification, and one fracture of the femoral neck in a case of polyarthritis. In 45 of these cases, follow-up has been continued for at least one year. X-ray signs of injury are frequent and seen in one out of two cases, but are no more frequent than in classical total prothesis and are therefore not alarming. The result of this technique with respect to pain is the same as for total prothesis. Mobility of the hip is maintained and is markedly improved when the hip was stiff prior to the operation. The major indication for this operation is osteoarthritis of the hip in patients 40 to 65 years of age for whom medical treatment is ineffective and where osteotomy cannot be performed. One fundamental point must be underlined: this technique must not jeopardize possible later surgery for total prothesis, and surgical technique must therefore be adapted with this in mind.