why would a muscle biopsy be done?

Answer 1

To test the internal muscle. I got them done in my legs when I was used as a guinea pig at university. Got paid $70 and ended up with a damaged nerve, all in the name of science! But I know women with breast cancer have had to have biopsies done too.

Answer 2

A muscle biopsy may be performed for many reasons, including the following:

To distinguish between neurogenic (nerve) and myopathic (primarily muscle) disorders
To identify specific muscular disorders such as muscular dystrophy or congenital myopathy
To identify metabolic defects of the muscle
To diagnose diseases of the connective tissue and blood vessels (such as polyarteritis nodosa)
To diagnose infections that affect the muscles (such as trichinosis or toxoplasmosis)

A muscle biopsy can reveal conditions such as the following:

Atrophy (loss of muscle mass)
Necrosis (tissue death) of muscle fibers
Inflammation of the muscle
Necrotizing vasculitis
Myopathic changes (destruction of the muscle)
Muscular dystrophy, indicated by antibody staining of the muscle biopsy specimen that can show deficient dystrophin
Traumatic muscle damage
Duchenne's muscular dystrophy
Polymyositis
Dermatomyositis

Additional conditions under which the test may be performed include the following:

Becker's muscular dystrophy
Charcot-Marie-Tooth disease (hereditary)
Common peroneal nerve dysfunction
Eosinophilic fasciitis
Facioscapulohumeral muscular dystrophy (Landouzy-Dejerine)
Familial periodic paralysis
Friedreich's ataxia
Polymyalgia rheumatica
Senile cardiac amyloid
Thyrotoxic periodic paralysis

What the risks are

The risks are minimal and may include the following:

Infection (a slight risk any time the skin is broken)
Bleeding of the site
Bruising of the area
Damage to the muscle tissue or other tissues in the area (very rare)

Answer 3

This biopsy is done for a variety of reasons: to distinguish between nerve and muscle disorders, to identify specific muscular disorders such as muscular dystrophy, to probe muscle metabolic activities, and to detect muscle infections such as trichinosis and toxoplasmosis. Biopsy of a muscle necessarily involves nerves, as muscle is highly infused by nerves. The small amount of muscle that is extracted during a muscle biopsy does not damage nerves to such an extent that muscle function is affected