Normal proximal and delayed distal conduction in the pudendal nerves of patients with idiopathic (neurogenic) faecal incontinence.

The latency of the response in the external anal sphincter muscle following transcutaneous stimulation of the cauda equina at the L1 vertebral level was measured in nine women with neurogenic faecal incontinence (mean 7.3 SD 0.7 ms) and 11 normal subjects (mean 5.6 SD 0.6 ms) (p = 0.01). There was no difference in conduction velocity between the L1 and L4 vertebral levels thus supporting the suggestion that conduction delay in faecal incontinence occurs distally.