Fast bowling in the game of cricket requires repetitive spinal extension, lateral deviation, lumbar flexion and thoracodorsal rotation. Back pain is common, and it has been shown that pars interarticularis defects had occurred in over 50% of a group of teenage fast bowlers. Many of these defects will heal, but some cause chronic pain which prevents bowling, although other activities may be painless. We report the successful results of local screw fusion of the pars interarticularis defects in ten bowlers, and recommend this method for this small group of sportsmen.

The action of fast bowling in the game of cricket is known to cause injuries to the lumbar spine. We studied a group of 16- to 18-year-old fast bowlers, selected for special training in Western Australia. All 24 had MR scans of the spine, 22 had radiographs and CT scans; in 20 the bowling technique was analysed biomechanically. There was a high incidence of back pain and this was always associated with a radiological abnormality. Pars interarticularis defects were diagnosed in 54% and intervertebral disc degeneration in 63%. Bowling actions which involved counter-rotation were associated with a higher incidence of both injuries.

Trendelenburg's test of function of the hip joint was first reported before radiology was available. At least four methods of performing it have since been described in the literature. We examined 50 normal subjects and 103 people with disorders affecting either the spine or the hip, in order to determine the different responses that occurred when they were asked to stand on one leg. This has enabled us to define a standard method of performing the Trendelenburg test, and to interpret the test as a method of assessing hip abductor function. The major pitfalls that result in misinterpretation, or false-positive responses, are pain, lack of cooperation from the patient, and impingement between the rib cage and the iliac crest. False-negative responses result from the patient using muscles above and below the pelvis, and from leaning beyond the hip on the standing side.

One hundred patients with acute ruptures of the lateral ligaments of the ankle were randomly allocated either to conservative treatment in a plaster cast or to operative repair. With the aid of stress tenography, the extent of the injury was established. There were 30 patients with isolated anterior talofibular ruptures and 20 with additional calcaneofibular ligament ruptures in each treatment group. Operative repair was associated with a higher incidence of complications in the first weeks, and slightly delayed the patients' return to work. At an independent two-year review there was no evidence that operative repair offered improved symptomatic or functional benefit.

Injuries to the tarsometatarsal (Lisfranc) joint are not common, and the results of treatment are often unsatisfactory. Since no individual is likely to see many such injuries, we decided to make a retrospective study of patients from five different centres. In this way 119 patients with injuries of the Lisfranc joint have been collected. This paper classifies these injuries and describes their incidence, mechanism of production, methods of treatment, results and complications. Sixty-nine of the patients attended for review: 35 of these had been treated by closed methods, 27 had had an open reduction and seven patients had had no treatment. On the basis of our study we suggest that these injuries should be classified according to the type of injury rather than the nature of the deforming force and that their treatment be based upon this classification. It seems that, whatever the severity of the initial injury, prognosis depends on accurate reduction and its maintenance.

A study was undertaken to assess the degree of inter-observer error when a panel of observers classified the radiographs of patients with early Perthes' disease, using Catterall grouping and "at risk" signs. The anteroposterior and lateral radiographs, taken within three months of diagnosis of Perthes' disease, were available for 69 hips and were shown in turn to 10 observers. The radiological end-results were assessed at least four years from diagnosis. The results showed a poor ability of the observers to delineate Groups 1, 2 and 3, with a more satisfactory performance in Group 4 and when Groups 2 and 3 were combined. Interpretation of "at risk" signs was unsatisfactory except when there was an increase in medial joint space greater than two millimetres. The end-results correlated well with early Catterall grouping and "at risk" signs when these were correctly interpreted.