Tendonitis

Chronic, or long-term, tendon problems are common among athletes. Tendonitis is especially common in people who play certain types of sports. Tendon problems account for almost 30 percent of all running injuries and 40 percent of all tennis injuries.

We use the term tendonitis, which means inflammation of the tendon, to refer to these chronic tendon problems. Sports medicine specialists now know that tendons do not always become inflamed when injured. Other changes in the tendon can cause tendon pain. However, tendonitis is still the most commonly used term.

What are Tendons?

Tendons connect muscle to bone. A tendon is made of material called collagen. Collagen is considered a connective tissue, because it forms tough strands that are like the strands of a nylon rope. Like the strands in a rope, the strands of collagen line up. The more strands, and the better they line up, the stronger they are. The tendon is wrapped in a thin, slippery covering called the tendon sheath. The tendon sheath allows the tendon to slide easily against the tissues around it.

Many parts of a tendon can be injured. Tendon problems can involve the area where the tendon attaches to the bone, the tissue that surrounds the tendon (the sheath), or the main tissues of the tendon. Sports medicine specialists use different terms to refer to injuries of different parts of the tendon.

Symptoms of Tendonitis

Tendonitis causes pain. This is the primary symptom of tendonitis and tendonosis. The affected tendons are sometimes swollen. In some cases this swelling occurs from actual thickening of the tendon itself. In other cases the swelling comes from thickening or swelling of the tendon sheath. Tendon problems often cause pain after resting, such as when you first get up in the morning. This pain usually goes away within minutes, or even seconds.

The pain or swelling of tendonitis may make the joint hard to move. Some types of tendon problems cause crepitus, a crackling feeling when the joint moves. In rare instances, the weakened tendon may actually rupture or break with a sudden force.

Where do most tendon problems develop?

Tendon problems can develop in any tendon of the body. Repetitive stress on the tendon is the most common cause. Some tendons are more susceptible to tendonitis than others.

Achilles Tendon

The Achilles tendon sheath, the tissues of the tendon, and the attachment to the heel bone can all become injured. Damaged Achilles tendons carry a higher risk of rupturing due to the weight they bear. See Achilles Tendon Problems for more information.

Biceps Tendon

Inflammation in the main tendon that attaches the top of the biceps muscle to the shoulder is caused by continuous or repetitive shoulder actions. See Biceps Tendonitis.

Posterior Tibial Tendon

Tendonitis along the inside edge of the ankle and into the instep of the foot is called posterior tibial tendonitis. It is usually caused by age-related degeneration and overuse.

Patellar and Quadriceps Tendon

Problems in the tendons of the knee occur mostly in people whose exercise involves running or jumping. Patellar tendonitis is also called jumper's knee.