Tendonitis Facts and Statistics: What You Need to Know

Tendonitis is a clinical condition characterized by inflammation to a muscle’s tendon. Tendons connect muscles to bones, and tendon inflammation is often caused by too much activity with not enough rest. Symptoms of tendonitis include tendon pain, soreness, and tenderness that worsen with contraction of the associated muscle and generally improve with rest.

This article will review important facts and statistics about tendonitis, including causes, risk factors, and screening methods. 

How Common Is Tendonitis?

About 30% of all healthcare visits for musculoskeletal conditions (those that affect muscles, bones, joints, tendons, and ligaments) affect the tendon, including tendonitis.

Some areas of the body are more likely to develop tendonitis, such as the:

• Common tendon of the wrist extensors (tennis elbow)
• Common tendon of the wrist flexors (golfers elbow) 
• Achilles’ tendon (Achilles' tendinitis)
• Patellar tendon (jumper's knee)
• Tendons of the thumb (deQuervain's tenosynovitis)

The most common type of tendonitis of the upper body affects the wrist extensors at the elbow while the most common type of tendonitis of the lower body affects the Achilles’ tendon of the ankle and the patellar tendon of the knee.

Causes of Tendonitis and Risk Factors

Tendonitis is an overuse injury in which a tendon becomes repeatedly stressed through repetitive muscle contraction. This stress occurs when muscles contract for a high amount of repetitions and/or with a large amount of resistance, which causes micro-tearing of the muscle and tendon fibers. Without adequate rest from activity to allow the micro-tears to heal, the tendon becomes inflamed, causing pain and swelling that requires rest to heal.

Tendons are specialized forms of connective tissue that can transmit forces from contracting muscles. Healthy tendons grow stronger when collagen is initially broken down with exercise and then built up as the body recovers. If the tendon does not receive adequate rest, the collagen is broken down at a faster rate than it can heal and rebuild, resulting in tendonitis from tendon inflammation.

Other risk factors that can cause the collagen of tendons to break down faster than it can heal include:

• Smoking
• Obesity
• High cholesterol

Tendonitis by Age and Gender

The rate at which collagen is rebuilt within tendons is also heavily influenced by age and gender. There is an increased risk of tendon injuries with older age due to the body’s slower healing rate and decreased activity of tendon cells to rebuild collagen.

Also, decreased synthesis of collagen and rebuilding of tendon fibers after exercise is more likely to affect females than males due to hormonal differences.

Screening and Early Detection

Early screening can help prevent tendonitis from getting worse and causing permanent damage to the structure of the affected tendon. Tendon pain that worsens with muscle contraction is the main symptom that should alert you to rest from aggravating movements until your symptoms subside. 

If symptoms continue after resting from aggravating movements for more than four weeks, you should schedule an appointment with a healthcare provider for further diagnosis and treatment. Your healthcare provider may use ultrasound to diagnose your tendonitis and determine if it is progressing to tendinosis, a chronic condition that causes degeneration of tendon fibers.

If tendonitis is caught early on, rest and physical therapy to rebuild strength in the tendon and associated muscle can help heal tendonitis and prevent it from coming back. Eccentric exercises, which are those that involve a slow and controlled relaxation of muscle contraction under tension, are most often used to improve tendon strength.

Treatment

Treatment for tendonitis initially involves rest from aggravating activities. Pain-relieving methods like ice and medications like nonsteroidal anti-inflammatory drugs (NSAIDs), such as Advil or Motrin (ibuprofen) and Aleve (naproxen), can be used to reduce pain and swelling, decrease inflammation, and reduce muscle spasm.

If chronic pain persists, a cortisone injection into your affected tendon may help decrease pain and inflammation. Once the severity of your symptoms starts to subside, a structured physical therapy program focusing on stretching and strengthening of surrounding muscles can help you to recover.

For chronic forms of tendonitis that do not heal with conservative treatment methods, a surgical procedure called a tenotomy may be performed. A tenotomy involves cutting into a tendon to promote increased healing. This may require completely cutting a tendon in two, which separates it from where it attaches to bone, or making tiny cuts along the length of the tendon while still keeping the attachment of the tendon intact.

Summary

Tendonitis is a condition that develops when a tendon becomes inflamed from too much activity without enough rest. This causes the collagen within tendons to break down at a faster rate than it can heal and rebuild.

Tendonitis is more likely to affect older individuals than younger ones, females than males, and people who smoke, have obesity, or have high cholesterol as opposed to those who do not share these factors. Resting from aggravating activities and strengthening the tendon and its muscle through eccentric exercises can help treat tendonitis and prevent it from recurring.