Patellar tendon rupture. The importance of timely recognition and repair.

Patellar tendon rupture is not uncommon in active adults, although it occurs less often than rupture of the ligaments. The diagnosis is easily missed on initial examination. Delay of surgical treatment leads to a complicated repair and a less functional outcome. The key physical finding is inability to actively extend the affected leg. Patients may also have severe, rapid swelling and depression in the infrapatellar region. The mechanism of injury usually involves forced hyperflexion or rapid extension from a weight-bearing position. Radiographic findings include patella alta and possible subluxation. This case report described an infrapatellar tendon rupture in a patient with no underlying systemic disease or history of repetitive trauma.