EMG, single fibre EMG and sacral reflexes in assessment of sacral nervous system lesions

Abstract

EMG of pelvic floor muscles, single fibre EMG of external anal sphincter and both bulbocavernous and anal reflexes were investigated in 31 men without sacral nervous system lesions and in 12 patients with neurogenic erectile impotence, of whom one had slight loss of sensitivity to pinprick in the lower sacral dermatomes. EMG and single fibre EMG abnormalities have been found concomitantly in 8 patients and 6 of these had also prolonged bulbocavernosus reflex latencies. In 2 patients the prolonged bulbocavernosus reflex latency was the only abnormality. Single fibre EMG of anal sphincter muscle seems to be superfluous in routine evaluation of sacral nervous system lesions.