Single-incision combination biopsy (muscle and nerve) in the diagnosis of neuromuscular disease in children.

The diagnosis of specific neuromuscular diseases in infants and children is often suspected clinically and confirmed histologically by muscle biopsy. In relatively few cases, the differential diagnosis includes hereditary or acquired peripheral neuropathies, and nerve biopsy is required for diagnosis. Historically, children who needed both muscle and nerve biopsies have had two separate incisions at the thigh (muscle) and ankle (nerve) to obtain the specimens. A procedure has been developed that employs a single incision on the posterior aspect of the calf, which allows for simultaneous muscle (soleus or peroneals) and nerve (sural) biopsies. A retrospective study of 22 patients who underwent single-incision combination biopsy was performed. Age at time of biopsy ranged from 2 months to 14 years. Adequate specimens for histologic analysis were obtained in all but one case. Histologic diagnoses were made in 32% of the muscle biopsies and 29% of the nerve biopsies. Mean follow-up after biopsy was 3 years 6 months. Potentially significant complications of nerve biopsy were not seen in this cohort. Single-incision combination biopsy is the preferred technique when simultaneous muscle and nerve biopsies are required. Knowledge of the location of the sural nerve in the calf is essential. This technique is relatively less invasive than separate muscle and nerve biopsies, allows for the harvest of adequate muscle and nerve specimens, is minimally morbid, and can be performed on very young infants.