The development of an unconstrained elbow arthroplasty. A clinical review.

This paper describes the development, operative technique and results of an unconstrained total elbow arthroplasty. Forty-seven elbow replacements were carried out in 44 patients between 1974 and 1982. There was a high rate of loosening in the early condylar replacements. The results in patients with post-traumatic arthritis were poor. The later design employs an ulnar stem, with a humeral stem if the distal humeral bone stock is poor. When used in carefully selected patients with rheumatoid arthritis, pain is reduced significantly, stability and movement are preserved and function is improved.

Intertrochanteric fractures: a comparison between fixation with a two-piece nail plate and Ender's nails.

The progress of 182 patients who presented with intertrochanteric fractures was followed over a six month period. Eighty-seven patients were treated using Thornton/McLaughlin nail plates and 95 were treated using Ender's intramedullary nails. Each fracture was classified according to radiological position and mechanical stability. The results show that the more unstable fractures are more likely to develop unsatisfactory results. Post operatively, the different mechanical complications have been recorded at various stages. Those fractures fixed with a nail plate tended to develop varus deformity resulting from either bony collapse around the implant or implant failure, whereas those fixed with Ender's nails did not develop deformity at the fracture site but encountered distal migration of the nails at the knee. The use of a classification system in predicting post operative mechanical complications is considered, and the comparative merits and disadvantages of the two fixation systems is discussed, with suggestions for improvement in operative technique.

The assessment of adolescent hallux valgus before and after first metatarsal osteotomy--clinical and walkway studies.

A comprehensive method of evaluating the feet of patients with adolescent hallux valgus both before and after surgical correction is described. Serial clinical, photographic and radiological studies were made and a dynamic assessment of gait was carried out using a load-sensitive walkway. Observations were made on 36 feet in which hallux valgus was treated by a modification of the Wilson oblique metatarsal osteotomy, with removal of a wedge of bone and screw fixation. In the first six months after operation, there was a lateral shift of the weight-bearing pattern in the forefoot and less weight was taken on the toes, but there was a tendency to return to the pre-operative distribution of weight during the next four years. Persistence of the lateral shift of weight-bearing appeared to result from elevation of the first metatarsal head secondary to shortening of the first metatarsal during the osteotomy. This can be avoided by deliberate depression of the first metatarsal head at the time of operation and fixation of the fragments in the required position with a screw.

Forces under the hallux valgus foot before and after surgery.

Abnormalities in the hallux valgus foot and changes after surgery were investigated by measuring the distribuiion of load on the foot in walking. Hallux valgus was associated with reduced load imposed on the toes, and on the medial side of the forefoot, compared with a large sample of healthy feet. Abnormalities correlated with the degree of the deformity. Both Keller's operation and a wedge displacement osteotomy of the first metatarsal not only failed to restore normal loading but increased the abnormalities of loading seen preoperatively. A large decrease in the angle between first and second metatarsals as a result of surgery minimized this increase. A silastic arthroplasty did not carry high loads when used to treat hallux valgus, but near normal loads were imposed on it when used for hallux rigidus. Considerable variability was found in the loading distribution on the healthy feet. The distribution between first and second metatarsal heads was partially dependent upon their protrusions, relative to the direction of walking. The changes in the relationships between the loadings on the forefoot and skeletal shape in response to surgical operations are important for our understanding of treatment of the hallux valgus foot.