Postural effects on lung and chest wall volumes in late onset type II glycogenosis patients

Respiratory failure (weak diaphragm) is lethal in late-onset type II glycogenosis. We aimed to study diaphragmatic weakness and the respiratory muscles impairment. Seated and supine spirometry and optoelectronic plethysmography were performed. The supine fall of vital capacity is due to diaphragm and abdominal weakness. Supine abdominal contribution to tidal volume is an index of diaphragmatic weakness.