Avulsion of the cartilaginous femoral origin of the anterior cruciate ligament in a three-year-old child. A case report with a thirteen-year follow-up.

Abstract

Rupture of the anterior cruciate ligament is rarely seen in children because the ligament is stronger than the physes during childhood, meaning that trauma to the knee will more likely result in a physeal fracture1-3. DeLee and Curtis, in 1983, reported only three cases of midsubstance rupture of the anterior cruciate ligament in their study of 388 knee ligament injuries in children4. Although some recent studies have demonstrated an increasing prevalence of midsubstance rupture of the anterior cruciate ligament in children and adolescents, most of those ruptures occurred during puberty or adolescence5-7. Conversely, osteochondral avulsion fractures of the tibial origin of the anterior cruciate ligament in children are relatively common8-11. Injuries that stress the anterior cruciate ligament most often result in an osteochondral avulsion fracture of the tibial eminence. Although there have been many studies of osteochondral avulsion fracture of the tibial eminence in children, only four cases of osteochondral avulsion fracture of the femoral origin of the anterior cruciate ligament have been reported12-15. It is also known that cartilaginous avulsion fractures of the tibial eminence can occur but are very rare16,17. Furthermore, a review of the orthopaedic literature revealed only one report of an isolated cartilaginous avulsion fracture of the femoral origin18. That fracture occurred in a three-year-old boy, but the duration of follow-up was only ten weeks. Therefore, we are aware of no reports regarding the long-term effects of cartilaginous avulsion fractures of the femoral origin of the anterior cruciate ligament. It is known that residual anterior laxity occurs after an osteochondral fracture of the tibial eminence19-21. Growth disturbance is also a concern. Mylle et al. reported on the premature …