Overview
Patellar tendonitis is an injury that affects the tendon connecting the kneecap (patella) to the shinbone. The patellar tendon, along with the quadriceps muscle and tendon, allows the knee to be straightened out, and provides strength for this motion. Patellar tendonitis is a common overuse injury that occurs when repeated stress is placed on the patellar tendon. The stress results in tiny tears in the tendon, which the body attempts to repair. But as the tears in the tendon become more numerous, the body can’t keep up, causing the inflammation in the tendon to worsen. When overuse is the cause of patellar tendonitis, patients are usually active participants in jumping types of sports, such as basketball or volleyball. Patellar tendonitis also may be seen with sports such as running and soccer. Also, some patients develop patellar tendonitis after sustaining an acute injury to the tendon, and not allowing adequate healing. This type of traumatic patellar tendonitis is much less common than in overuse syndromes.
Causes
Overuse
Participation of jumping sports
Tight leg muscles
Muscular imbalance
Symptoms
Pain between the kneecap (patella) and shin bone (tibia)
Diagnosis
Physical examination and medical history consultation
X-rays
Blood tests
Aspiration
MRI
Treatment
Rest
Anti-inflammatory medications
Stretching exercise
Support straps or braces
Surgery
Source: http://www.upmc.com/Services/sportsmedicine/injuries/knee/Pages/patellar-tendonitis.aspx ; http://www.mayoclinic.com/health/patellar-tendinitis/DS00625