We made a prospective arthroscopic study of 106 skeletally mature male sportsmen with an average age of 28.35 years (16.8 to 44) who presented with an acute haemarthrosis of the knee due to sporting activities. We excluded those with patellar dislocations, radiographic bone injuries, extra-articular ligamentous lesions or a previous injury to the same joint. The anterior cruciate ligament (ACL) was intact in 35 patients, partially disrupted in 28 and completely ruptured in 43. In the patients with an ACL lesion, associated injuries included meniscal tears (17 patients), cartilaginous loose bodies (6), and minimal osteochondral fractures of the patella (2), the tibial plateau (3) or the femoral condyle (9). We found no age-related trend in the pattern of ACL injuries. Isolated injuries included one small osteochondral fracture of the patella, and one partial and one total disruption of the posterior cruciate ligament. Three patients had cartilaginous loose bodies, and no injury was detected in five. Acute traumatic haemarthrosis indicates a serious ligament injury until proved otherwise, and arthroscopy is needed to complement careful history and clinical examination. All cases with a tense effusion developing within 12 hours of injury should have an aspiration. If haemarthrosis is confirmed, urgent admission and arthroscopy are indicated.

The moulded baby syndrome comprises: head moulding (plagiocephaly); pelvic obliquity with unilateral loss of hip abduction in flexion; and occasionally scoliosis, torticollis and bat ears. The hips, however, are radiologically normal and do not require the treatment used in the management of congenital dislocation or dysplasia. A review of 67 hips confirms this finding.

We describe two boys with bilateral deformity of the upper end of the radius. The condition appears to predispose to non-traumatic posterior dislocation of the radial head and is associated with posterior bowing of the upper end of the ulna. This problem has not been previously described.