ACL Tear Or Not (Differential Diagnosis)

ACL tears can sometimes be confused with other injuries, especailly when it happens to a younger athletes. Even though increased number of ACL injuries in younger athletes are seen, it is still rare compared to older population. Since, in those younger athletes, the weak link is their growth plate instead of the ligament itself, an injury to open growth plate (physis) becomes more common. The ligament can pull a piece of bone off of tibial plateau, which can happen by the same mechanisms of injury as an ACL tear. This can be detected by plain films. This injury is also different from ACL tears in that this can be repaired surgicaly not having to have it reconstructed.

Another injury that can be confused with ACL tears is petalla subluxation. This is due to similarities of both injuries. They both happen from similiar mechanisms of injury. Clinical presentations are similiar, such as immediate swelling, loss of motion, etc. Another reason for this is that medical professionals have to a tendency to think "knee injury = ligament injury?!" Those medical professionals need to do a thourough evaluation of the injury to avoid misdiagnosis.

A key to a quick recovery from an injury that has happended is to find out what the injury is and have it taken care of early and appropriately.

With patellar subluxation, the patella (knee cap) dislocates and it goes back in place by itself. So, there is no need for reduction. It may need to be immobilized, however. Most of the times, the patella dislocates/subluxes lateraly.