We measured the effect of arthroscopic lavage and debridement of the osteoarthritic knee by comparing objective measurements of thigh muscle function before and after operation. There was some improvement in quadriceps isokinetic torque at six and 12 weeks after joint lavage but not after debridement. Neither method significantly relieved the patients' symptoms.

1. Correction of hallux valgus by spike osteotomy of the neck of the first metatarsal is described, and the results in eighty-two feet are presented.

2. A high proportion of satisfactory results can be obtained, but great care is needed in both selection and technique.

3. The ideal case is one of moderate deformity, without degenerative arthritis, and with symptoms referable to increased width of the forefoot; the operation should not be performed in cases with obvious degenerative change, nor when metatarsalgia is a prominent symptom.

4. It is important to displace the metatarsal head as far laterally as possible, and vital to avoid dorsal angulation or displacement.

5. It is suggested that enough is now known about the natural evolution of hallux valgus and the results of some operations for prophylactic surgery to be undertaken in carefully selected cases.