The effects of sacral denervation on bladder and urethral function.

Complete sacral denervation resulted in loss of anal sphincter, detrusor and urethral skeletal muscular activity, but resting urethral smooth muscular sphincter tone was unaffected. The Credé and Valsalva maneuvers in the patients studied did not produce voiding. Spinal anesthesia, however, resulted in a loss of urethral smooth muscular activity. These results affirm the importance of an intact sympathetic nerve supply in maintaining urinary continence.