Sexual function after major resections of the sacrum with bilateral or unilateral sacrifice of sacral nerves.

The sexual function of nine patients with severance of sacral nerves bilaterally (five patients) or unilaterally (four patients), performed during operations for radical extirpation of tumors of the sacrum or its vicinity, was studied. Sexual histories were obtained and sensibility tests were performed. In four of the five male patients an attempt was made to collect electromyographic recordings from the external urethral and anal sphincters during ejaculation. Bilateral loss of S3 to S5 nerves in two women seemed not to affect their sexual function. Bilateral loss of S2 to S5 nerves in one man was compatible with gratifying sexual intercourse, the stimulation for erection being purely psychogenic, and "ejaculation" of a dripping nature. Unilateral loss of all sacral nerves did not impair previously normal sexual function, although the penises and vulvae of these patients were anesthetic on one side. The sensibility of the penis seemed to be subserved by the second sacral nerve. The myoelectric activity of the striated urethral and anal sphincters during ejaculation recorded in one patient with unilateral total loss of sacral nerves was normal bilaterally considering the duration of, and intervals between, the clonic contractions.