Biodegradable screw presents as a loose intra-articular body after anterior cruciate ligament reconstruction

We report a case of intra-articular movement of a broken piece of a poly-L-lactide (PLLA) bioabsorbable interference screw from the femoral tunnel in anterior cruciate ligament (ACL) reconstruction with quadrupled semi-tendinosus and gracilis tendon grafts. Eleven months after initially successful ACL surgery, the patient felt a sudden locking of the knee without associated trauma or injury. The patient experienced pain and swelling episodes after heavy lifting with knee flexion at work, but without symptoms of giving way or locking. On revision arthroscopy, a broken part of a bioabsorbable interference screw was seen in the lateral compartment, which was subsequently removed without incident. The semitendinosus-gracilis graft appeared intact without disruption. After revision surgery, the patient's recovery was uneventful, with return to activity within a few months. This case further shows the problem of biointerference screw breakage in ACL reconstructive surgery and the need to bury the femoral bioabsorbable interference screw on graft fixation.