Arthroscopically Confirmed Complete Healing of Anterior Cruciate Ligament Avulsion Fracture Following Four-Corner...

We report a case of tibial insertion avulsion fracture of the anterior cruciate ligament (ACL). A 10-year-old boy who fell from a skateboard was diagnosed with a tibial insertion avulsion fracture of the ACL and was treated arthroscopically. The avulsed fragment was provisionally fixed with guide pins inserted into its four corners, and the lateral view was checked to avoid penetration of the growth plate. Two ultrahigh-molecular-weight polyethylene tapes were passed through the ACL just above its tibial insertion, pulled through the four-corner bone tunnels in an X-shaped configuration, and tightened. The patient was immobilized for 3 weeks, and partial weight bearing was initiated at 4 weeks. Bone union was confirmed at 6 months using plain radiographs, and second-look arthroscopy and implant removal were performed 8 months postoperatively. During arthroscopy, complete union with smooth continuity of the articular cartilage at the fracture site and a stable ACL were observed. The patient had a full knee range of motion and no pain at the final follow-up.