We measured torsion of the humeral head in 38 patients (40 shoulders) with recurrent anterior dislocation of the shoulder (RADS) and in 40 normal subjects. We found a reduced mean retroversion in the patients with RADS at 4.3 +/- 10.56 degrees (17 degrees anteversion to 32 degrees retroversion) as compared with 16.1 +/- 11.07 degrees in the control group (0 degrees to 49 degrees) (p = 0.0001). There was anteversion in 11 of the 40 shoulders in the RADS group (27.5%) and in none of the control group. The first dislocation had occurred after minimal force in 18 of 25 patients with less than 10 degrees retroversion, but in only three of 15 with over 10 degrees retroversion. We conclude that decreased retroversion of the humeral head is often associated with RADS and with first dislocation of the shoulder caused by minimal force.

The significance of the posterior cruciate ligament in the stability of the knee was investigated in dogs and it was compared with that of the anterior cruciate ligament by studying the changes produced in the knee after transection of either ligament. Osteophyte formation and changes in articular cartilage were less prominent after division of the posterior cruciate ligament. A complete longitudinal tear of the medial meniscus was found in eight out of the 10 dogs who had undergone section of the anterior cruciate but in none of the 10 with section of the posterior cruciate. It appears that, in dogs at least, the posterior cruciate ligament is less important than the anterior in the stability of the knee.

A high stress fracture of the fibula which occurred in 48 out of a class of 120 recruits doing a difficult jumping exercise is described. No more were seen when the exercise was stopped. The importance of this report is that it confirms the theory that different muscular activities cause different stress fractures.