Recurrent Dislocation of the Patella

This small series would seem to show that almost any operative technique adequately performed will prevent redislocation and give good early results. The long-term results, however, are very disappointing. A sturdy of the natural history of the condition suggests that the reason for these poor results is that operations are performed late in the presence of unsuspected but severe degenerative changes. It is suggested that the damage sustained by the articular surface of the patella is due much more to the abnormal excursions of the patella which occur with normal flexion and extension of the knee than to the occassional episodes of dislocation. In view of this, it is felt that surrgical intervention should be undertaken early, in the hope that movement of the patella can be restored to normal before the articular cartilage is destroyed. As it is impossible to assess accurately the degree and extent of articular degeneration by clinical means, it is surggested that the knee joint be opened and inspected in patients on whom operation is performed and, if there is marked damage, the patella should be excised, and the pull of the quadriceps should be re-aligned. Probably the easiest way of re-aligning the pull of the quadriceps is to transplant the tibial tubercle medially. This operation is very successful in adults but has certain hazards when performed on children. If the severe damage to the patellar cartilage which frequrently occurrs is unnnoticed or is ignored, the patient will probably be condemned to an early onset of osteo-arthritis in the knee, with a final result as disappointing as those in patients on whom no operation has been performed.