Knee or patellar tendonitis occurs when the patella tendon is overstressed, which can happen when jumping or landing heavily. The condition is often called jumper's knee. Patella is the medical term for the kneecap, and the patellar tendon connects the kneecap to the shinbone. Tendons are made up of strong tissue and join muscles to bones. If a person applies extra stress to a tendon, tiny tears can develop in the tissue causing inflammation, but the injury often heals quickly. However, repeated strains may cause tears to develop faster than the body can mend them.
Patellar tendonitis develops gradually. The condition becomes more severe each time the tendon is overstressed, so it is essential to rest the knee after each injury and see your primary doctor.
The main symptom of patellar tendonitis is pain and tenderness just below the kneecap. The pain usually starts after exercise, and continued exercise will likely increase the discomfort. Jumping, running, and landing are likely to make the pain worse. A person may begin to notice weakness in the knee, particularly during exercises that put pressure on this part of the body.