Congenital muscular dystrophy: case reports and reappraisal.

We report four cases of congenital muscular dystrophy; all demonstrated hypotonia and multiple contractures at birth. Strength remained stationary or improved, but the tendency for contracture formation persisted. Brief small amplitude polyphasic potentials were recorded on electromyography, and muscle biopsy revealed extensive fat and/or collagen replacement, which was out of proportion to fiber necrosis or patient strength. The consistent clinical and pathologic features of these patients and others described in the literature justify considering this disorder to be a specific nosologic entity.