Muscle biopsy
Biopsy - muscleA muscle biopsy is the removal of a small piece of muscle tissue for examination.
How the Test is Performed
This procedure is usually done while you are awake. The health care provider will apply a numbing medicine (local anesthesia) to the biopsy area.
There are two types of muscle biopsy:
- A needle biopsy involves inserting a needle into the muscle. When the needle is removed, a small piece of tissue remains in the needle. More than one needle stick may be needed to get a large enough sample.
- An open biopsy involves making a small cut in the skin and into the muscle. The muscle tissue is then removed.
After either type of biopsy, the tissue is sent to a laboratory for examination.
How to Prepare for the Test
No special preparation is usually needed. If you will have anesthesia, follow instructions on not eating or drinking anything before the test.
How the Test will Feel
During the biopsy, there is usually little or no discomfort. You may feel some pressure or tugging.
The anesthetic may burn or sting when injected (before the area becomes numb). After the anesthetic wears off, the area may be sore for about a week.
Why the Test is Performed
A muscle biopsy is done to find out why you are weak when the doctor suspects you have a muscle problem.
A muscle biopsy may be done to help identify or detect:
- Inflammatory diseases of muscle (such as polymyositis or dermatomyositis)
Polymyositis
Polyarteritis nodosa is a serious inflammatory blood vessel disease. The small and medium-sized arteries become swollen and damaged.
Read Article Now Book Mark ArticleDermatomyositis
Polymyositis and dermatomyositis are rare inflammatory diseases. (The condition is called dermatomyositis when it involves the skin. ) These disease...
Read Article Now Book Mark Article - Diseases of the connective tissue and blood vessels (such as polyarteritis nodosa)
- Infections that affect the muscles (such as trichinosis or toxoplasmosis)
Trichinosis
Trichinosis is an infection with the roundworm Trichinella spiralis.
Read Article Now Book Mark ArticleToxoplasmosis
Toxoplasmosis is an infection due to the parasite Toxoplasma gondii.
Read Article Now Book Mark Article - Inherited muscle disorders such as muscular dystrophy or congenital myopathy
Muscular dystrophy
Muscular dystrophy is a group of inherited disorders that cause muscle weakness and loss of muscle tissue, which get worse over time.
Read Article Now Book Mark Article - Metabolic defects of the muscle
- Effects of medicines, toxins, or electrolyte disorders
Electrolyte
Electrolytes are minerals in your blood and other body fluids that carry an electric charge. Electrolytes affect how your body functions in many ways...
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A muscle biopsy may also be done to tell the difference between nerve and muscle disorders.
A muscle that has recently been injured, such as by an EMG needle, or is affected by a pre-existing condition, such as nerve compression, should not be selected for a biopsy.
EMG
Electromyography (EMG) is a test that checks the health of the muscles and the nerves that control the muscles.
Read Article Now Book Mark ArticleNormal Results
A normal result means the muscle is normal.
What Abnormal Results Mean
A muscle biopsy can help diagnose the following conditions:
- Loss of muscle mass (atrophy)
Atrophy)
Muscle atrophy is the wasting (thinning) or loss of muscle tissue.
Read Article Now Book Mark Article - Muscle disease that involves inflammation and a skin rash (dermatomyositis)
Dermatomyositis
Dermatomyositis is a disease that involves muscle inflammation and a skin rash. Polymyositis is a similar inflammatory condition that also involves ...
Read Article Now Book Mark Article - Inherited muscle disorder (Duchenne muscular dystrophy)
Duchenne muscular dystrophy
Duchenne muscular dystrophy is an inherited disorder. It involves muscle weakness, which quickly gets worse.
Read Article Now Book Mark Article - Inflammation of the muscle
- Various muscular dystrophies
- Destruction of the muscle (myopathic changes)
Myopathic changes
A muscle disorder includes patterns of weakness, loss of muscle tissue, electromyogram (EMG) findings, or biopsy results that suggest a muscle proble...
Read Article Now Book Mark Article - Tissue death of the muscle (necrosis)
(necrosis)
Necrosis is the death of body tissue. It occurs when too little blood flows to the tissue. This can be from injury, radiation, or chemicals. Necro...
Read Article Now Book Mark Article - Disorders that involve inflammation of the blood vessels and affect muscles (necrotizing vasculitis)
Necrotizing vasculitis
Necrotizing vasculitis is a group of disorders that involve inflammation of the blood vessel walls. The size of the affected blood vessels helps to ...
Read Article Now Book Mark Article - Traumatic muscle damage
- Paralyzed muscles
- Inflammatory disease causing muscle weakness, swelling tenderness, and tissue damage (dermatomyositis or polymyositis)
Polymyositis
Polymyositis and dermatomyositis are rare inflammatory diseases. (The condition is called dermatomyositis when it involves the skin. ) These disease...
Read Article Now Book Mark Article - Nerve problems that affect the muscles
- Muscle tissue under the skin (fascia) becomes swollen, inflamed, and thick (eosinophilic fasciitis)
Eosinophilic fasciitis
Eosinophilic fasciitis (EF) is a syndrome in which tissue under the skin and over the muscle, called fascia, becomes swollen, inflamed and thick. Th...
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There are additional conditions under which the test may be performed.
Risks
The risks of this test are small, but may include:
- Bleeding
- Bruising
Bruising
Bleeding into the skin can occur from broken blood vessels that form tiny red dots (called petechiae). Blood also can collect under the tissue in la...
Read Article Now Book Mark Article - Damage to the muscle tissue or other tissues in the area (very rare)
- Infection (a slight risk any time the skin is broken)
References
Shepich JR. Muscle biopsy. In: Fowler GC, ed. Pfenninger and Fowler's Procedures for Primary Care. 4th ed. Philadelphia, PA: Elsevier; 2020:chap 188.
Warner WC, Sawyer JR. Neuromuscular disorders. In: Azar FM, Beaty JH, eds. Campbell's Operative Orthopaedics. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 35.
Muscle biopsy - illustration
A muscle biopsy involves removal of a plug of tissue usually by a needle to be later used for examination. Sometimes more than one needle insertion may be needed to obtain a large enough specimen. If there is a patchy condition expected an open biopsy may be used. Open biopsy involves a small incision through the skin and into the muscle, so that a sample of muscle tissue can be removed from the affected area. There may be some slight bruising or bleeding at the site but the risks are minimal with the procedure.
Muscle biopsy
illustration
Muscle biopsy - illustration
A muscle biopsy involves removal of a plug of tissue usually by a needle to be later used for examination. Sometimes more than one needle insertion may be needed to obtain a large enough specimen. If there is a patchy condition expected an open biopsy may be used. Open biopsy involves a small incision through the skin and into the muscle, so that a sample of muscle tissue can be removed from the affected area. There may be some slight bruising or bleeding at the site but the risks are minimal with the procedure.
Muscle biopsy
illustration
Review Date: 7/21/2022
Reviewed By: Diane M. Horowitz, MD, Rheumatology and Internal Medicine, Northwell Health, Great Neck, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.