A new case of congenital, hypotonic-sclerotic muscular dystrophy is presented. The patient showed congenital hyperlaxity and looseness of distal joints, muscle weakness, and spur-like protrusion of the calcaneus. Afterwards rapid progressive contractures of both knees and hip joints developed. Muscle biopsies revealed unequivocal dystrophic abnormalities and small atrophic fibers with numerous foldings of basal lamina suggestive of a neurogenic lesion. The disease presents clinical variability but the diagnosis is possible when a newborn shows: no dominant family history, slender body, marked distal joint laxity and hyperflexibility, proximal joint contractures and normal or slightly increased serum enzymes.