Is a Muscle Biopsy?
A muscle biopsy is a procedure that removes a small sample of
tissue for testing in a laboratory. The test can help your doctor to see if you
have an infection or disease in your muscles.
A muscle biopsy is a relatively simple procedure. It is usually
done on an outpatient basis, which means you will be free to leave on same day
as the procedure. You may receive local anesthesia. This will numb the area
where the doctor is removing the tissue from, but you will remain awake for the
Is a Muscle Biopsy Done?
A muscle biopsy is performed if you are experiencing problems
with your muscle and your doctor suspects an infection or disease could be the
cause. The biopsy can help your doctor rule out a certain condition as a cause
for your symptoms. It can also help them make a diagnosis and initiate a
Your doctor may order a muscle biopsy for various reasons. They
may suspect you have:
- defects in the way your muscles metabolize, or
- diseases that affect blood vessels or connective
tissue, such as polyarteritis nodosa (which causes the arteries to become
- infections related to the muscles, such as trichinosis
(an infection caused by a type of roundworm)
- muscular disorders, including types of muscular
dystrophy (genetic disorders that lead to muscle weakness and other symptoms)
Your doctor might also use this test to tell if your symptoms are
being caused by one of the muscle-related conditions above, or by a problem
with your nerves.
Risks of a Muscle Biopsy
Any medical procedure that breaks the skin carries some risk of
infection or bleeding. Bruising is also possible. However, since the incision
made during a muscle biopsy is small — especially in needle biopsies — the risk
is much lower.
Your doctor will not take a biopsy of your muscle if it was
recently damaged in another procedure — for instance, by a needle during an
electromyography (EMG) test — or if it’s already known to have nerve damage.
There is a small chance of damage to the muscle where the needle
enters, but this is rare. Always talk with your doctor about any risks before a
procedure and share your concerns.
to Prepare for a Muscle Biopsy
You don’t need to do much to prepare for this procedure.
Depending on the type of biopsy you will have, your doctor may give you some
instructions to carry out before the test. These instructions typically apply
to open biopsies.
It’s always a good idea to tell your doctor about any
prescription drugs, over-the-counter medications, and herbal supplements you
are taking prior to a procedure. You should discuss with them whether you
should stop taking them before and during the test, or if you should change the
a Muscle Biopsy Is Performed
There are two different ways to perform a muscle biopsy.
The most common method is called a needle biopsy. For this
procedure, your doctor will insert a thin needle through your skin to remove your
muscle tissue. Depending on your condition, the doctor will use a certain type
of needle. These include:
- core needle biopsy: a medium-sized needle
extracts a column of tissue, similar to the way core samples are taken from the
- fine needle biopsy: a thin needle is
attached to a syringe, allowing fluids and cells to be drawn out
- image-guided biopsy: this kind of needle
biopsy is guided with imaging procedures — like X-rays or computed tomography (CT)
scans — so your doctor can avoid specific areas like your lung, liver, or other
- vacuum-assisted biopsy: this biopsy uses
suction from a vacuum to collect more cells
You will receive local anesthesia for a needle biopsy, and should
not feel any pain or discomfort. In some cases, you may feel some pressure in
the area where the biopsy is being taken. Following the test, the area may be
sore for about a week.
If the muscle sample is hard to reach — as may be the case with
deep muscles, for instance — your doctor may choose to perform an open biopsy.
In this case, your doctor will make a small cut in your skin and remove the
muscle tissue from there.
If you are having an open biopsy, you may receive a general
anesthesia. This means you will be sound asleep throughout the procedure.
a Muscle Biopsy
After the tissue sample is taken, it’s sent to a laboratory for
testing. It could take up to a few weeks for the results to be ready.
Once the results are back, your doctor may call you or have you
come to their office for a follow-up appointment to discuss the findings.
If your results come back abnormal, it could mean you have an
infection or disease in your muscles, which may be causing them to weaken or
die. Your doctor may need to order more tests to confirm a diagnosis or see how
far the condition has gone. They will discuss your treatment options with you
and help you plan your next steps.