Purpose of the study A prospective observational study to ascertain any correlation between joint laxity and knee hyperextension to anterior cruciate ligament rupture.

Methods used Joint laxity as defined by Beighton’s method and hyperextension of uninjured knee in 169 patients with symptomatic isolated anterior cruciate ligament rupture was recorded in a prospective fashion. This was correlated to the scores obtained in a selected group of age and sex matched controls

Results 72 out of 169 of the patients had hyperlaxity in their joints and 133 out of 169 had knee hyperextension. In the control group 14 out of 65 had hyperlaxity in their joints and 24 out of 65 had knee hyperextension.

Statistical analysis showed that ACL injury was common in those with lax joints and with knee hyperextension with a p < 0.001

Conclusion ACL injury is common in patients with joint laxity especially in those with knee hyperextension.

We wish to report our observations on a prospective series of 22 patients with high energy posterolateral corner injuries undergoing surgery at our Unit.

Since 1997, all patients presenting to our Unit with posterolateral corner injuries were analysed prospectively. Twenty two patients are presented with a mean follow-up of two years. Thirteen patients underwent acute exploratory surgery within two weeks of injury. The majority of patients had four or more injured structures identified at operation. The surgery involved reattachment of the injured structures together with selective staged intra-articular reconstruction in high demand individuals. Nine patients were referred to our unit a number of years after their original accident. The majority of these chronic cases underwent popliteofibular reconstruction using semitendinosus. All patients from both groups returned to activities of daily living after surgery. Ten patients returned to sport after reconstruction. Eight out of ten of these had undergone acute reconstruction.

Posterolateral corner injuries are high-energy multiple ligament injuries. Acute repair with staged selective intra-articular reconstruction in our series led to 61% of the acute patients returning to sport. Only 22% of the patients presenting late, returned to sport after reconstruction. This suggests that patients are more likely to return to sport if their knees are reconstructed early and we would encourage an assertive approach to these high-energy injuries.