What is it?
A tendon is a thick band that attaches a muscle to a bone. The patellar tendon goes from the bottom of the kneecap (patella) to the top of the shinbone (tibia). Patellar tendinopathy, otherwise known as “jumper’s knee,” is an overuse injury caused by stress on the tendon that may end up causing tiny tears within the tendon leading to degeneration. The term “tendinopathy” or “tendinosis” is now preferred over “tendonitis.” Tendonitis suggests inflammation, but in this condition, very little true inflammation occurs.

Risk Factors
• Repetitive running and jumping • Repetitive cutting/pivoting, or changing direction in sport • Increase in training volume or intensity

Symptoms
Symptoms include pain at the front of the knee that is worse with jumping, changing direction, or slowing speed of activity. A sports medicine physician may find soreness along the bottom part of the kneecap and along the tendon with pressure. Sometimes, there is swelling along the tendon as well. X-rays may help investigate the problem to check how the kneecap lines up, as well as to look for calcium build-up, arthritis, or a fracture.

Sports Medicine Evaluation and Treatment
Patellar tendinopathy is treated first with rest. It is helpful to limit the stress on the tendon while it is trying to heal. Stretching and strengthening the buttocks and thigh muscles (front – quadriceps, back – hamstrings) are very important in the treatment. Knee braces, knee straps, and ice may help with pain and swelling and sometimes, anti-inflammatory medicine for pain relief is used as well. As the pain improves, a key part of treatment is working up to strengthening the muscles while they are being lengthened rather than being shortened (called “eccentric exercises”). Those types of exercises may help to strengthen the tendon and may even heal tiny tears. However, the tendon heals very slowly, so the rehabilitation often takes several months.

Injury Prevention
• Focus on proper leg strengthening exercises working the core muscles, buttocks, hips, and legs • Gradually increase training

Return to Play
Most athletes can return to sports when they are able to run, do squats, and hop on the injured leg without pain. It is important to keep up with some strengthening exercises going back to sports.

AMSSM Member Authors
Gloria G. Rho, MD and Susan M. Joy, MD

References
Brukner, Peter and Karim Kahn. Clinical Sports Medicine, 4th ed. Sydney, Australia: McGraw-Hill Australia Pty Ltd, 2012. Print.
Murtaugh, Bryan and Joseph Ihm. Eccentric Training for the Treatment of Tendinopathies. Current Sports Medicine Reports 2013: 175-182.