Tendons are tough, flexible bands of tissue that connect muscles to bones. Tendons can be small, like the delicate bands in the hands, or large, like the ropelike cords that anchor the calf or thigh muscles.
When tendons become inflamed, irritated or suffer microscopic tears, the condition is called tendonitis. In most cases, the cause of tendonitis is unknown; when a cause can be identified, the condition usually happens for one of two reasons:
- overuse – a particular body motion is repeated too often.
- overload – the level of a certain activity, such as weightlifting, is increased too quickly.
Common locations of tendonitis
Shoulder. The most common form of tendonitis in the shoulder is rotator cuff tendonitis. It involves the tendon of the supraspinatus muscle, which attaches to the upper portion of the upper arm bone at the shoulder joint. Sometimes the tendon of the infraspinatus muscle is affected. The injury usually occurs from overuse, typically in an occupation or sport that requires the arm to be elevated repeatedly. People at risk include carpenters, painters, welders, swimmers, tennis players, and baseball players.
Elbow. Two forms of tendonitis commonly involve the elbow.
- Lateral epicondylitis (tennis elbow) causes pain on the outer side of the elbow joint. This condition probably affects 40% to 50% of all adult athletes who play racquet sports. It also can be caused by any activity that repeatedly twists and flexes the wrist, such as pulling weeds, using a screwdriver or even carrying a briefcase.
- Medial epicondylitis (golfer's elbow) causes pain on the inner side of the elbow. Despite its name, it is more likely to be related an occupation that requires repeated elbow movements, such as construction work, than to sports. When it does occur as a sports injury, medial epicondylitis can be triggered by repeatedly swinging a golf club or throwing a baseball.
Knee. Jumper's knee, the most common form of knee tendonitis, involves either the patellar tendon at the lower edge of the kneecap or the quadriceps tendon at the upper edge of the kneecap. It is a common overuse injury, especially in basketball players and distance runners.
Wrist. Wrist tendonitis usually appears in the form of de Quervain's disease, a condition that causes pain in the back of the wrist at the base of the thumb. Although de Quervain's disease usually occurs in people who repeatedly grasp or pinch with the thumb, it sometimes develops during pregnancy or for no known reason.
Achilles tendonitis. This form of tendonitis affects the Achilles tendon, the large ropelike tendon attached to the heel bone at the back of the foot. Achilles tendonitis usually is caused by overuse, especially in sports that require running or repeated jumping, and it accounts for 15% of all running injuries. Achilles tendonitis also may be related to faulty running technique or to poorly fitting shoes, if the back of the shoe digs into the Achilles tendon above the heel. Sometimes Achilles tendonitis is caused by an inflammatory illness, such as ankylosing spondylitis, reactive arthritis, gout, or rheumatoid arthritis.
Tendonitis usually causes pain in the tissues surrounding a joint, especially after the joint is used too much during play or work. In some cases, the joint may feel weak, and the area may be red, swollen, and warm to the touch.
Other symptoms vary according to which tendon is affected:
- rotator cuff tendonitis: usually dull, aching shoulder pain that can't be tied to one location. The pain often extends into the upper arm toward the chest, and may be worse at night and interfere with sleep.
- tennis elbow: pain in the outer side of the elbow. Sometimes the pain extends down to the forearm and wrist.
- golfer's elbow: pain in the inner side of the elbow
- jumper's knee: pain is usually below the kneecap but sometimes above it
- de Quervain's disease: pain at the back of the wrist, near the base of the thumb
- Achilles tendonitis: pain at the back of the heel or 2 to 4 inches above the heel
Your description of your symptoms is an important part of diagnosing tendonitis. To get a complete picture, your doctor will probably ask you questions about your pain:
What does your pain feel like (sharp, dull, burning)?
Where is your pain located? Is it limited to one area or does it spread away from the joint to involve a wider area?
Do you have tingling, numbness, or weakness near where the pain is?
When did your pain start? Did it begin after a sudden increase in your work activities or exercise? Might it be related to any new sport or exercise that you've recently tried?
What makes it feel better, and what makes it worse?
Does the pain disappear when you rest the area, or is it present even at rest?
A physical exam is also important. During it your doctor will look for tenderness, swelling, redness, muscle weakness, and limited motion near the sore tendon. He or she may ask you to move in certain ways, such as raising your arm above your head or bending your wrist. These moves may hurt, but they are very important to help figure out which tendon is affected. In most cases, a diagnosis can be made based on your answers to your doctor's questions and a physical examination.
Some people need blood tests to look for other causes of inflammation around the joints, such as gout or rheumatoid arthritis. X-rays also may be taken to confirm that there is no fracture, dislocation, or bone disease. In people with Achilles tendonitis or rotator cuff tendonitis, ultrasound or MRI scans can help evaluate the extent of tendon damage.
The quicker tendonitis is treated, the sooner recovery can begin.
A first step in treatment may rest. Not using the affected muscles and tendons for a few days to a few weeks gives the body time to repair itself. For example, people with golfer's elbow usually need to rest the affected elbow for at least one month.
Ice is another treatment. Apply ice packs to the painful area for 20-minute periods, three or four times a day. You also should ice the area immediately after any activity that aggravates your pain, such as tennis or running.
Taking a nonsteroidal anti-inflammatory drug such as ibuprofen, naproxen, or aspirin can relieve pain and swelling.
Depending on the location and severity of the tendonitis, you may to wear a splint, brace, or sling for a short time. It is important to gently and regularly move the joint to avoid getting a stiff, or "frozen," joint. This is particularly important for tendonitis involving the shoulder.
If your tendonitis is serious, a physical therapist may be able to give you specialized local treatments such as deep heat treatments using ultrasound, friction massage, or water therapy to improve joint mobility. A physical therapist can also guide you through a rehabilitation program to help you to regain strength, motion, and function.
Surgery is rarely needed to treat tendonitis. It is an option mainly when tendonitis doesn't respond to other treatments or when there is significant tendon damage that is unlikely to improve with any other treatment.