In order to better understand patellar tendinitis it is important to understand the anatomy and function of the knee and the patellar tendon. Please review the section on knee anatomy before reviewing this section.
The kneecap (patella) is a small bone in the front of the knee. It glides up and down a groove in the thigh bone (femur) as the knee bends and straightens. The patellar tendon is a thick, ropelike structure that connects the bottom of the patella to the top of the large shin bone (tibia). The powerful muscles on the front of the thigh, the quadriceps muscles, straighten the knee by pulling at the patellar tendon via the patella. Patellar tendinitis is the term used to describe inflammation of the patellar tendon.
Patellar tendinitis usually occurs as a result of overdoing an activity and placing too much stress on the patellar tendon before it is strong enough to handle the stress. This overuse results in "micro tears" in the patellar tendon which leads to inflammation and pain. Over time damage to the patellar tendon can occur. In extreme cases, the patellar tendon may become damaged to the point of complete rupture.
Patellar tendinitis is common in people involved in activities that include a lot of running, jumping, stopping and starting. Pain from patellar tendinitis is felt in the area just below the patella. There may be swelling in and around the patellar tendon and it may be sensitive to touch. The pain can be mild or in some cases the pain can be so bad that it prevents athletes from playing their sport. This condition is also known as "jumper's knee" because it is frequently seen in sports that require a lot of jumping.
Examination techniques that detect tenderness and swelling in or around the patellar tendon are helpful in determining if someone has patellar tendinitis. X-rays are occasionally done to make sure that the patellar tendon does not have any calcium in it. Other tests such as diagnostic ultrasound or Magnetic Resonance Imaging (MRI) are sometimes used to rule out more extensive damage to the patellar tendon.
Treatment of patellar tendinitis may include relative rest, icing, medications to reduce inflammation and pain, stretching, strengthening exercises or a patellar tendon strap. Patellar tendinitis may be prevented by easing into jumping or running sports and by using good training techniques. Off-season strength training of the legs, particularly the quadriceps muscles, can also help. Doctors and physiotherapists trained in treating this type of overuse injury can outline a treatment plan specific to each individual.
Please visit the links section for additional information on patellar tendinitis. Links have been provided to other websites as well as online medical journals. Other knee injury topics can also be accessed.