What is Muscular Fibrosis?

Muscular fibrosis is the excessive formation of fibrous bands of scar tissue in between muscle fibers. Although fibrosis may develop in any organ, the only two known kinds of muscular fibrosis are skeletal muscle fibrosis and cardiac muscle fibrosis. The abnormal development of fibrosis may cause muscle weakness, fatigue, and an inability to perform simple daily activities.

When fibrous connective tissue is formed in moderate amounts, it is a normal part of the muscle’s healing process. Fibrous scar tissue develops after the muscle has been damaged to fill in the open spaces in the injured muscle, providing more surface area for the regenerating muscle fibers to adhere to. The connective tissue cells that comprise scar tissue are unable to contract and relax to enable movement. Once the overproduction of fibrous scar tissue begins, the muscle becomes progressively weaker.

Cardiac fibrosis occurs when abnormal amounts of fibrous scar tissue are formed within the heart muscle. The overgrowth of the scar tissue may happen after a heart attack or occur as heart disease progresses, and the heart muscle becomes stiff and unable to pump blood efficiently. Many people commonly experience chest pain and fatigue after cardiac fibrosis begins.

Skeletal muscle fibrosis may be a symptom of a muscle disorder. Some people with Duchenne or Becker muscular dystrophy develop large amounts of fibrous tissue as the healthy muscle tissue degrades. Lou Gehrig’s disease, or amyotrophic lateral sclerosis (ALS), is a disabling condition that causes the formation of large amounts of muscular fibrosis after denervation, or separation of the nerve, and atrophy of skeletal muscle.

Diagnosis of skeletal muscular fibrosis may be done after a series of tests are administered. A biopsy of muscle tissue can be screened for the presence of fibrous tissue within the muscle. Physical evaluation of functional muscle strength may indicate abnormal weakness common after the formation of fibrosis. Other factors that may indicate fibrosis in the muscle are poor posture and reduced coordination when walking or performing daily activities.

The pain and limited mobility caused by muscular fibrosis may be treated by a combination of methods. Physical therapy may be advised to stretch the muscle affected by fibrosis, which may build up strength and promote easier movement of the muscle. Non-steroidal anti-inflammatory drugs (NSAIDs) and the application of ice packs may be recommended to relieve any pain and stiffness in the muscle.

Surgery may be necessary to remove the fibrous bands of scar tissue from the skeletal muscle. Removal of the fibrosis may allow healthy muscle fibers to develop. The procedure may include a proximal resection of the muscle or surgical release of the fibrous band. After the surgery, the muscle will be immobilized for several weeks to allow for optimal muscle fiber regeneration.