[Isolated congenital aplasia of the anterior cruciate ligament treated by reconstruction in a 5-year-old boy].

Agenesia of the anterior cruciate ligament is a rare entity which is exceptionally symptomatic. We report a case observed in a 5-year-old boy who presented an unstable knee which was treated by Clocheville ligamentopàlasty. At five years followup, the functional outcome was satisfactory. The patient was symptom free and practiced sports activities. He did not develop any complications excepting flexion which was limited to 130 degrees . Magnetic resonance imaging demonstrated good integration of the autograft. Anterior instability in the child limits physical activity and can cause meniscal injury and early osteoarthritis. The Clocheville technique is adapted for pediatric patients with knee instability caused by a congenital defect or injury.