Intrinsic Healing of the Anterior Cruciate Ligament in an Adolescent.

The anterior cruciate ligament (ACL) is an important ligamentous stabilizer of the knee. The natural primary healing potential of the ACL has been shown to be extremely poor. We report the case of a 12-year-old boy who was involved in a motor vehicle collision and sustained a grade IIIB open tibial fracture, distal fibula fracture, medial and lateral meniscus tears, avulsion fracture of the femoral metaphysis, and anterior and posterior cruciate ligament tears. Because of delayed union of his tibia fracture, treatment of the ligamentous injuries was postponed to 16 months after initial injury. However, magnetic resonance imaging at that time showed complete healing. At 20 months, the patient returned to competitive hockey. Based on this case, we believe there is some natural primary healing potential within the ACL.