Article Details

The management of chronic patellar tendon tears is challenging because of the unopposed proximal migration resulting from the action of the Quadriceps muscles. This retraction makes it difficult to reduce and maintain the patella in its original location. This condition is rare and is seen among individuals who present late to the hospital after a knee injury. The injury usually affects patients in their third and fourth decades of life [1]. In older patients, these injuries are commonly the result of isolated trauma with a forceful indirect contraction of the quadriceps. In patients under 40, there is often an underlying microtrauma from repetitive injury [2]. A force of 17.5 times body weight is estimated to cause a rupture; by comparison, the patellar tendon experiences a force of 3.2 times body weight while ascending stairs. Forces on the patella are greatest at 60 degrees of flexion, and ruptures are most common at the distal pole of the patella as the tensile load is greatest at the insertion site [3].