Revision of Mueller total hip arthroplasties.

Experience with 65 revisions of Mueller total hip arthroplasties and a minimum of two years follow-up on 32 revised total hips showed that the results appear to be poor in a significant number (22%) of patients: 18% required additional surgery. Revision of total hip arthroplasties with recementing of one or both components carries a significant risk of intraoperative and postoperative complications. Since the introduction of femoral components with improved metallurgic properties, no stem failures have occurred. Varus position of the femoral stem predisposes for stem loosening. Aspiration arthrography is of limited value in the evaluation of a painful total hip. In cases of femoral component loosening with gross cystic changes on the roentgenograms, early revision is recommended as fracture of the femoral shaft may ensue. Late loosening of the acetabular cup as yet appears to be an uncommon cause of total hip arthroplasty failure. Attention to the details of surgical technique and more research on material selection in primary total hip replacement are important.

Removal of methylmethacrylate in failed total hip arthroplasties. An improved technique.

Extraction of methylmethacrylate from the proximal shaft of the femur following failure of total hip replacement arthroplasty can be accomplished efficiently by osteotomy of the greater trochanter and the use of variable sized carbide drills and a long flexible penlight.

Transient osteoporosis of the hip in pregnancy.

A patient is presented with transient osteoporosis of the hip occurring in the third trimester of pregnancy. This syndrome is characterized by hip pain, limited motion, and osteoporosis of the femoral head with preservation of the joint space. The syndrome is self-limited with full recovery in three months to one year. Treatment is symptomatic with bedrest, protected weight-bearing, and analgesics as needed. The cause of this syndrome remains unknown.