Sacrolumbar intersegmental reflex circuit in men and its relation to the ejaculatory process.
OBJECTIVE
We aimed to investigate electrophysiologically the intersegmental reflex circuit from sacral to lumbar cord segments in normopotent adult men, in patients with spinal cord injury and in patients with premature ejaculation.


METHODS
Reflex EMG activity of the cremasteric (CM) and bulbocavernosus (BC) muscles was recorded simultaneously by needle electrodes during electrical stimulation of the upper lumbar and sacral dermatomes, respectively. Thirty-three healthy male volunteers, 16 patients with spinal cord injury (SCI) at the thoracic or cervical levels, and 26 men with premature ejaculation (PME) were included in the study.


RESULTS
In controls, upper lumbar dermatomal stimulation (ULS) at the inner side of thigh only elicited a reflex response from the CM muscle and did not produce a regular response from the lower sacral myotomes such as in the BC muscle. However lower sacral dermatomal stimulation (LSS) at the dorsal nerve of penis consistently evoked reflex responses from both CM and BC muscles. These basic electrophysiological features were not different in patients with SCI. LSS did not elicit a reflex response from the CM muscle in about 39% of patients with PME, while the BC reflex was obtained from all patients with PME.


CONCLUSIONS
The neurophysiological pattern in BC and CM muscles during sacral or lumbar dermatomal stimulation reflects the sacrolumbar intersegmental reflex linkage that may be related to the ejaculatory process in men. The intersegmental sacrolumbar reflex circuit may be functionally disturbed in some patients with PME.


CONCLUSIONS
Interaction between the reflex activity of sacral to lumbar dermatomes could prove useful in defining electrophysiological mechanisms related to ejaculation in men.
Ertekin
Cumhur
C
Department of Clinical Neurophysiology, Ege University, Medical School Hospital, Izmir, Turkey. erteker@unimedya.net.tr
Uysal
Hilmi
H
Bademkiran
Fikret
F
Altay
Baris
B
D000328:Adult; D004542:Ejaculation / Q000502:physiology* / Q000528:radiation effects; D004558:Electric Stimulation / Q000379:methods; D004576:Electromyography / Q000379:methods; D006801:Humans; D008160:Lumbosacral Plexus / Q000503:physiopathology* / Q000528:radiation effects; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D011930:Reaction Time; D012021:Reflex, Abnormal / Q000502:physiology*; D012735:Sexual Dysfunction, Physiological / Q000503:physiopathology; D013119:Spinal Cord Injuries / Q000503:physiopathology