The quadriceps tendon is located just above the kneecap (patella) and connects the quadriceps muscles in the front of the thigh to the top of the kneecap. The patellar tendon is located just below the kneecap. It connects the kneecap to the shinbone (tibia). The function of the quadriceps tendon and patellar tendon is to work with the muscles in the front of the thigh to straighten the knee. Therefore, both tendons are instrumental in allowing people to perform activities such as climbing stairs, walking, running, and jumping.
Tendinopathy is a common overuse injury caused by repeated and prolonged stress on a tendon. This repeated stress (micro-trauma) on the tendon can lead to the tendon becoming thickened and tiny tears developing in the tendon. The body attempts to repair these tiny tears, but if the rate of breakdown within the tendon exceeds the rate of repair, this can lead to pain and dysfunction.
Patellar tendinopathy is a common disorder in athletes who participate in sports that require jumping such as volleyball and basketball and has been labeled “jumper’s knee.” It is also commonly seen in athletes involved in sports such as track and field, gymnastics, and tennis. However, quadriceps and patellar tendinopathy can occur in any individual who is active, especially those who may have recently increased their physical activity.