Isolated iliotibial band rupture after corticosteroid injection as a cause of subjective instability and knee pain in a military special warfare trainee.

Iliotibial band friction syndrome (ITBFS) of the knee is a common overuse injury in athletes, especially in runners. The syndrome occurs when the ITB, a lateral thickening of the fascia lata of the thigh moves repetitively over the lateral femoral condyle. A variety of nonoperative measures are used for ITBFS treatment, including stretching, core strengthening, and therapeutic injection. Isolated distal ITB rupture is a rare entity and has never yet to be reported in the orthopedic literature. We present a case of isolated ITB rupture as a cause of varus instability and knee pain in a Naval Special Warfare candidate diagnosed with ITBFS and previously treated with several local corticosteroid injections before ITB rupture. Because of continued knee pain and a sense of instability, along with an inability to return to his military special warfare duties, the ITB was surgically repaired. This case highlights the presentation and management of isolated distal ITB rupture and discusses some of the potential risk factors for rupture, including prior local corticosteroid injection.