[A case of sciatica with hypertrophy of the calf].

Hypertrophy of the calf associated with sciatica is rare. In the present case there was hypertrophy, predominantly of type I fibers, which showed a high percentage to the detriment of type II fibers. In the previously reported cases, the type of hypertrophied fibers was variable and pseudomyotonic discharges were inconstantly recorded. The mechanism underlying the hypertrophy is unknown. Inequality of size of muscle fibers could result from proximity of atrophic fibers and those with compensatory hypertrophy. The increased proportion of type I fibers could be the consequence of compensatory hypertrophy induced by lesions of synergic muscles and/or muscle compartments.