Risks and alternatives
The risks associated with muscle biopsies are very small. The commonest problem after needle biopsy is bleeding, usually resulting in some localised bruising. Rarely the bruising may be more extensive causing swelling of the region and very rarely this may require medical attention. With all neuromuscular conditions, care must be taken when using general anaesthetics, and for this reason local anaesthetics are preferred where possible. For all muscle biopsies it is assumed that the patient is at risk for malignant hyperthermia (an adverse reaction) and the precipitating anaesthetic agents are avoided, so the risk is negligible There is a small risk of muscle damage and infection, but these are very rare. It is not uncommon to have a patch of numbness around the scar which may last for a few weeks.
Special arrangement are required for patients on Warfarin or other anticoagulants, and a clear plan made prior to biopsy.
Is there an alternative?
A muscle biopsy is a standard procedure when testing for most muscle conditions. Molecular genetic testing is available for some conditions and a muscle biopsy may not be necessary, but this applies to only a few disorders. It is common for these conditions to be excluded using a blood sample before a muscle biopsy is performed.