A retrospective series of 272 operatively proven bucket-handle tears of the meniscus has been studied to define the natural history of the tear and to assess the accuracy of arthrography as a diagnostic technique. A simple twist, or a sporting injury accounted for most tears in the 196 patients on whom information was sufficient to allow analysis. There was, however, either no known trauma or merely a history of crouching in 20 per cent of patients. These were distributed evenly throughout the age range. Most of the 272 patients presented either with a locked knee (43 per cent) or with a history of locking (37 per cent). Fifty per cent of those with a previous history of locking but who were clinically unlocked at the time of operation, had displaced bucket-handle tears, indicating that unlocking of the knee joint frequently represents anterior extension of the tear, rather than relocation of the displaced fragment of meniscus. Significant meniscal tears were identified in 77 per cent of the 187 arthogram reports that were studied. Most errors in diagnosis seemed to occur when the separated fragment was hidden in the intercondylar notch and the peripheral rim was misinterpreted as an intact meniscus.

The effect of calcaneal traction on the compartmental pressure in the legs of five individuals with tibial fractures was studied. Mean resting pressures without traction were found to be 31.9 mmHg for the deep posterior compartment and 27.0 mmHg for the anterior compartment. For each kilogram weight of traction applied the deep posterior pressure rose by 5.7 per cent of the resting value and the anterior pressure by 1.6 per cent. It is suggested that the weight of traction should be only sufficient to render the patient comfortable and maintain alignment of the limb. Excessive traction is likely to increase the risk of compartmental ischaemia. The application of six kilograms of traction would raise the mean resting pressure by 34 per cent from 31.9 to 42.7 mmHg.