Life-threatening respiratory failure due to a previously undescribed myopathy.

The case of a young man with a previously undescribed myopathy associated with polydactyly is reported. Although both limb girdles were affected, the major effect of the disease was upon the respiratory muscles leading to his presentation with life-threatening respiratory failure. A further feature was pronounced stiffness of the vertebral column and limb girdles, similar in some respects to the 'rigid spine syndrome'. Muscle biopsy appearances were unique but showed some similarities to both nemaline myopathy and myotonic dystrophy. Ventilatory assistance at night using a rocking bed led to a marked improvement and has enabled the patient to return to full-time employment.