Three groups of patients with upper motor neuron lesions were studied. A first group consisted of 19 patients with complete lesions and 3 patients with incomplete lesions. All had an unbalanced bladder function which required surgical interventions. A second group consisted of 9 patients with chronic complete lesions who achieved balanced bladder function spontaneously. A third group consisted of 11 patients in the acute stage of injury. Polygraph recordings of pressure within the bladder, urethra, rectum and external anal sphincter were carried out with the help of video-tape monitoring and radiographic image intensification. Special catheter ballons with radiopaque markings were employed for pressure measurements. The behavior of the external urethral sphincter during spinal shock and the sequence of return of sacral somatic and visceral motor reflexes during recovery from spinal shock were investigated. It was shown that in spinal shock, the majority of patients retained sacral segment somatomotor reflex activity, in the absence of visceromotor activity, and that resistance values at the external urethral sphincter remained high. The highest resistance recorded in the membranous urethra was found to be located at the distal external sphincter, just before the bulb of the urethra.