Robert Wood Johnson University Hospital

Muscle Biopsy

Muscle Biopsy


Procedure overview

A muscle biopsy is a procedure used to diagnose diseases involving muscle tissue. Tissue and cells from a specific muscle are removed and viewed microscopically. The procedure requires only a small piece of tissue to be removed from the designated muscle.

The tissue sample is obtained by inserting a biopsy needle into the muscle. If a larger sample is required, your doctor may make an incision in the skin (open biopsy) and remove a larger section of muscle.

The muscle selected for the biopsy depends on the location of symptoms which may include pain or weakness. The muscles often selected for sampling are the bicep (upper arm muscle), deltoid (shoulder muscle), or quadriceps (thigh muscle).

A related procedure that may be used to diagnose neuromuscular problems is electromyography (EMG). EMG measures the electrical activity of muscle during rest, slight contraction, and forceful contraction. Please see this procedure for additional information.

Reasons for the procedure

A muscle biopsy is performed to assess the musculoskeletal system for abnormalities. Various disease processes can cause muscle weakness or pain. These conditions may be related to problems with the nervous system, connective tissue, vascular system, or musculoskeletal system.

A muscle biopsy helps to determine the source of the disease process ensuring initiation of appropriate treatment.

Muscle biopsies may be performed to diagnose neuromuscular disorders, infections that affect the muscle, and other abnormalities in the muscle tissue. The following is a list of some conditions diagnosed by muscle biopsy.

There may be other reasons for your doctor to recommend a muscle biopsy.

Risks of the procedure

As with any surgical procedure, complications can occur. Some possible complications may include, but are not limited to, the following:

There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.

Before the procedure

During the procedure

A muscle biopsy may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your doctor’s practices.
Generally, a muscle biopsy follows this process:

  1. You will be asked to remove clothing and will be given a gown to wear.
  2. During the procedure, you will need to lie as still as possible.
  3. The skin over the biopsy site will be cleansed with an antiseptic solution.
  4. As the doctor injects a local anesthetic to numb the area, you will feel a needle stick and a brief stinging sensation.
  5. Your doctor will insert the biopsy needle through the numbed skin, and into the muscle where the sample is taken. You may feel some pressure or pulling sensation during the procedure.
  6. If a larger sample is required, a small incision will be made into the skin’s surface. Sections of the muscle tissue may be cut using small, sharp scissors instead of a biopsy needle. You may feel mild discomfort when the muscle is cut.
  7. The biopsy needle will be withdrawn and firm pressure will be applied to the biopsy site for a few minutes, until the bleeding has stopped.
  8. The doctor will close the opening in the skin with adhesive strips or stitches, if necessary.
  9. A sterile bandage or dressing will be applied.
  10. The muscle tissue sample will be sent to the lab for examination.

After the procedure

Once you are home, it is important to keep the biopsy area clean and dry. Your doctor will give you specific bathing instructions. If stitches are used, they will be removed during a follow-up office visit. If adhesive strips are used, they should be kept dry and generally will fall off within a few days.

The biopsy site may be tender or sore for two to three days after a muscle biopsy. Take a pain reliever for soreness as recommended by your doctor. Aspirin or certain other pain medications may increase the chance of bleeding. Be sure to take only recommended medications.

Notify your doctor to report any of the following:

You may resume your usual diet and activities unless your doctor advises you differently. Your doctor may restrict your activity for 24 hours following the procedure and ask that you avoid excessive use of the biopsied muscle.

Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.

Online resources

The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease, or replace the professional medical advice you receive from your doctor. Please consult your health care provider with any questions or concerns you may have regarding your condition.

This page contains links to other websites with information about this procedure and related health conditions. We hope you find these sites helpful, but please remember we do not control or endorse the information presented on these websites, nor do these sites endorse the information contained here.

American Academy of Orthopaedic Surgeons

Muscular Dystrophy Association

Myositis Association

National Institute of Child Health and Human Development

National Institute of Neurological Disorders and Stroke

National Institutes of Health (NIH)

National Library of Medicine


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