Of all the overuse problems associated with physical activity, tendinitis is among the most common forms of knee trauma. In the past, all conditions have been termed tendinitis and treated accordingly. There now are several different pathological entities. These are: tendinitis, paratendinitis, tendinosis, partial and complete rupture.
Tendinitis is a catch term for inflammation of the tendon itself, and can often co-exist with paratendinitis.

The cause of tendinitis usually results from microscopic tears within the tendon and triggering an inflammatory response within the tendon. Common areas susceptible to tendinitis are; achilles, patella, adductor longus, supraspinatus, biceps, tibialis posterior and flexor hallucis longus tendons.

The first signs of tendinitis are usually noticed following exercise and especially first thing in the morning. During the warm-up phase of exercise the pain frequently disappears and only returns after the cool down period. Consequently, the sportsperson can train through the pain in the early stages and therefore interfering with the healing process.