Patellar tendonitis is characterized by inflammation and irritation of the patellar tendon, which connects the kneecap to the shin bone and works with the quadriceps (thigh muscle) and quadriceps tendon to allow the knee to straighten. This group of tissues also is responsible for allowing the knee to perform a kicking motion. Because patellar tendonitis most commonly affects athletes whose sports require repetitive jumping—including basketball, volleyball, and certain track and field events—it often is referred to as jumper’s knee. The pain associated with this condition usually occurs directly over the patellar tendon and may be worse with certain activities, especially jumping or kneeling. Many people affected by patellar tendonitis experience a crunching sensation known as crepitus when the knee is in motion. Diagnosis of this condition may involve the use of X-ray tests to rule out bone issues. In patients with chronic tendinitis, calcium deposits may be present. Patients may also undergo MRI testing to identify inflammation. Treatment of patellar tendonitis will vary depending on the type and severity of the inflammation and may include rest, administration of anti-inflammatory medications, application of ice, use of various supportive devices, and physical therapy to restore range of motion and normal movement. Surgery is very rarely used unless tendon damage is present.