What are the Different Types of Tendon Diseases?

Tendons are the thick, fibrous tissues that connect muscle to nearby body parts, usually bone, and assist with range of motion. Tendon disease results in the tendons not working properly, which is typically indicated by pain, swelling in the area, and reduced range of motion. Some tendons are covered by sheaths; some are not. The two main types of tendon diseases are tendinitis, or inflammation of the tendon itself, which affects tendons without sheaths, and tenosynovitis, inflammation of the tendon sheath, which affects tendons with sheaths.

Tendon diseases can affect any joint in the body. Common areas of tendon diseases in the upper body include the following: rotator cuff tendinitis, which affects the shoulder; bicipetal tendinitis, which affects the upper arm; lateral epicondylitis, otherwise known as tennis elbow; flexor or extensor tendinitis or tenosynovitis, each of which affects the wrist; de Quervain’s disease — sometimes spelled DeQuervain's disease — which affects the thumb joint; and Dupruytren’s Contracture, which affects the palm of the hand. The most common tendon diseases that affect the lower body include illotibial tendinitis, which affects the hip, pattelar tendinitis, which affects the knee and is sometimes called jumper’s knee, and peroneal tendinitis in the ankle.

For tendons without sheaths, tendinitis occurs when the tendon begins to shred, usually as the result of repetitive motion overuse, causing inflammation of the tendon itself. Tenosynovitis of tendons with sheaths, also most often the product of repetitive motion overuse, results when the synovial fluid that lubricates the tendon sheath fails. Sometimes the body does not produce enough synovial fluid or produces poor quality synovial fluid. This allows friction to occur between the tendon and the sheath, leading to swelling and thickening of the tendon that impairs proper function.

Bursitis is not a tendon disease per se but does affect tendon health. Bursitis occurs when the bursae, or fluid-filled sacs between the skin and tendons, become inflamed due to repetitive motion overuse, overexertion, or non-ergonomically correct posture. The most common sites where bursitis occurs are the shoulders, elbows, and hips.

Home treatment for tendon diseases includes resting the affected joint, applying ice to the affected joint, compression, or wrapping the joint with an elastic bandage, and elevating the affected joint above heart level. When home treatment fails to produce a reduction of symptoms, medical treatment may be required and could, depending on the nature of the tendon disease, involve surgery, casting, and physical therapy.