We report observations in a 32-year-old man with the following characteristics of rigid spine syndrome: humero-peroneal muscular atrophy and weakness; bradycardia, dilated cardiomegaly and complete cardiac conduction block; and severe fatty degeneration of the paravertebral and calf muscles. The latter showed a predominance of type 1 fibers, a deficiency of type 2A fibers, and an increase in type 2C fibers. The patient had no familial background of the disease. There was no contracture of the elbows. These findings, especially the severe cardiac involvement, suggest that the rigid spine syndrome can be difficult to distinguish from the Emery-Dreifuss form of muscular dystrophy.