Muscle and Nerve Biopsies
The Neuromuscular Center at Phoenix Neurological Associates offers
state of the art facilities for the performance and processing of muscle
and nerve biopsies.
A biopsy is a surgical procedure in which one or more small pieces of
muscle or nerve tissue are removed for further microscopic or biochemical
examination. The procedure, often used in the diagnosis of a neuromuscular
disorder, is considered "minor" surgery and can usually be
performed using a local anesthetic. We are able to perform these
biopsies in our Neuromuscular Center, so patients do not need to go to
a hospital. The procedure takes less than an hour and patients can go
home right after the biopsy.
Muscle Biopsy Procedure (24kb
Nerve Biopsy Procedure (38 kb PDF)
Post Biopsy Instructions (40
A doctor is likely to call for a muscle biopsy after looking at preliminary
blood tests, performing an electromyogram (EMG) and physical examination,
and determining that the patient's symptoms indicate an underlying neuromuscular
disorder. The muscle biopsy can help distinguish between muscular and
neurological problems and can help pinpoint the exact neuromuscular disorder
The neuromuscular specialist selects a muscle, usually the biceps, triceps,
deltoid or quadriceps muscle, that should yield the most information
about the disease. Usually moderately affected muscles are chosen, the
weakest muscles may already be too degraded for analysis. The procedure
involves a 2-to-3-inch incision, which is then closed with stitches and
may feel sore for a few days.
Most of the time, nerve disorders can be diagnosed without the need
for a nerve biopsy. However, a nerve biopsy can be a necessary and valuable
test in some patients, such as those suspected of having inflammation
of their nerves. As is the case for muscle biopsies, nerve biopsy is
an outpatient procedure that can be performed in our Neuromuscular Center.
Analyzing the Sample
All of the biopsies performed in our Neuromuscular Center are processed
in our CLIA certified pathology laboratory. This means the samples do
not have to be shipped to outside labs. Our highly trained technicians
cut them into many thin sections for examination. Using different tests
on different sections, we look at the tissue's overall appearance, chemical
activities in the tissue, and the presence or absence of critical proteins.
This analysis can yield information about muscle degeneration and regeneration,
fiber type abnormalities mitrochondrial abnormalities, scar tissue, inflammation
and other clues to specific disorders.The information these tests provide
helps determine exactly what disease and what form of it the person has.
Finally, a DNA analysis can be performed on a muscle sample to detect
a genetic mutation. Although a blood sample is usually adequate for a
DNA test, a muscle sample may be needed to test for mitochondrial DNA
Your doctor may occasionally recommend a new biopsy even though you've
had one in the past, especially if you've been given a tentative diagnosis
or now suspect your diagnosis was incorrect. With many new muscle-protein
antibodies now available for testing biopsy samples, as well as new understanding
of mitochondrial disorders and new DNA tests, a new biopsy may be desirable.
The analysis of a muscle biopsy sample is a very tedious and labor-intensive
process in which many sections of the muscle must be cut, many different
types of procedures performed, and the results carefully analyzed. Our lab
usually performs a few basic histology tests immediately after the biopsy
and then, based on these results, determines what further tests should
be conducted. The report is usually available within two weeks of the biopsy.