The aim of this study was to evaluate the functional and clinical outcome following medial patello-femoral ligament reconstruction using autogenous hamstring tendon grafts for patellar instability.

Over a 4 year period the senior author operated on 35 patients for lateral instability of the patella. The predominant initiating event was a sporting injury. Each patient had either failed conservative management including physiotherapy, or failed surgical management including tibial tuberosity transfer.

Post-operatively, all patients were allowed full flexion and extension. Sporting activity was restricted until 4-6 months post-operatively. Patients were evaluated clinically and functionally. The Fulkerson score was utilised pre- and post-operatively. The minimum follow-up was 6 months, the mean follow-up was 20 months. There were 18 males and 17 females. The mean age was 24.6 years. The mean pre-operative Fulkerson score was 59.3 (range 6-100). The mean post-operative Fulkerson score was 83.6 (range 25-100), the mean improvement was 24.3. 24 patients returned to sporting activities.

The main complications were one patient with a patella fracture that was stabilised with internal fixation, one patient requiring exploration and reinforcing the ligament which had attenuated. Both patients finally had a good clinical outcome.

Our study has shown that symptomatic lateral instability of the patella can be effectively treated with a medial patello-femoral ligament reconstruction and result in overall good clinical and functional outcome.

We would recommend this technique.