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Translumbar and transsacral motor-evoked potentials: a novel test for spino-anorectal neuropathy in spinal cord injury.

ABSTRACT: Spinal cord injury (SCI) causes anorectal problems, whose pathophysiology remains poorly characterized. A comprehensive method of evaluating spino-anorectal function is lacking. The aim of this study was to investigate the neuropathophysiology of bowel dysfunction in SCI by evaluating motor-evoked potentials (MEP) of anus and rectum following transspinal magnetic stimulation and anorectal physiology.Translumbar and transsacral magnetic stimulations, anorectal manometry, and pudendal nerve terminal motor latency (PNTML) were performed in 39 subjects with SCI and anorectal problems and in 14 healthy controls, and data were compared. MEPs were recorded with an anorectal probe containing bipolar ring electrodes.The MEPs were significantly prolonged (P<0.05) bilaterally, and at lumbar and sacral levels, as well as at rectal and anal sites in SCI subjects compared with controls. A total of 95% of SCI subjects had abnormal MEPs and 53% had abnormal PNTML. All subjects with abnormal PNTML also demonstrated abnormal MEP, but 16/17 subjects with normal PNTML had abnormal MEP. Overall, SCI patients had weaker anal sphincters (P<0.05), higher prevalence of dyssynergia (85%), and altered rectal sensation (82%).Translumbar and transsacral MEPs revealed significant and hitherto undetected lumbosacral neuropathy in 90% of SCI subjects. Test was safe and provided neuropathophysiological information that could explain bowel dysfunction in SCI subjects.

SUBMITTER: Tantiphlachiva K

PROVIDER: S-EPMC3883059 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Translumbar and transsacral motor-evoked potentials: a novel test for spino-anorectal neuropathy in spinal cord injury.

Tantiphlachiva Kasaya K Attaluri Ashok A Valestin Jessica J Yamada Thoru T Rao Satish S C SS

The American journal of gastroenterology 20110125 5

<h4>Objectives</h4>Spinal cord injury (SCI) causes anorectal problems, whose pathophysiology remains poorly characterized. A comprehensive method of evaluating spino-anorectal function is lacking. The aim of this study was to investigate the neuropathophysiology of bowel dysfunction in SCI by evaluating motor-evoked potentials (MEP) of anus and rectum following transspinal magnetic stimulation and anorectal physiology.<h4>Methods</h4>Translumbar and transsacral magnetic stimulations, anorectal m ...[more]

PMID: 21266960

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Project description:Fine motor skills are thought to rely on the integrity of ascending sensory pathways in the spinal dorsal column as well as descending motor pathways that have a neocortical origin. However, the neurophysiological processes underlying communication between the somatosensory and motor pathways that regulate fine motor skills during spontaneous recovery after spinal cord contusion injury remain unclear. Here, we established a rat model of cervical hemicontusive injury using C5 laminectomy followed by contusional displacement of 1.2 mm (mild injury) or 2.0 mm (severe injury) to the C5 spinal cord. Electrophysiological recordings were performed on the brachial muscles up to 12 weeks after injury to investigate the mechanisms by which spinal cord pathways participate in motor function. After spinal cord contusion injury, the amplitudes of somatosensory and motor-evoked potentials were reduced, and the latencies were increased. The forelimb open field locomotion test, grooming test, rearing test and Montoya staircase test revealed improvement in functions. With increasing time after injury, the amplitudes of somatosensory and motor-evoked potentials in rats with mild spinal cord injury increased gradually, and the latencies gradually shortened. In comparison, the recovery times of somatosensory and motor-evoked potential amplitudes and latencies were longer, and the recovery of motor function was delayed in rats with severe spinal cord injury. Correlation analysis revealed that somatosensory-evoked potential and motor-evoked potential parameters were correlated with gross and fine motor function in rats with mild spinal cord contusion injury. In contrast, only somatosensory-evoked potential amplitude was correlated with fine motor skills in rats with severe spinal cord injury. Our results show that changes in both somatosensory and motor-evoked potentials can reflect the changes in gross and fine motor functions after mild spinal cord contusion injury, and that the change in somatosensory-evoked potential amplitude can also reflect the change in fine motor function after severe spinal cord contusion injury. This study was approved by the Animal Ethics Committee of Nanfang Hospital, Southern Medical University, China (approval No. NFYY-2017-67) on June 11, 2017.

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Dataset Information

Translumbar and transsacral motor-evoked potentials: a novel test for spino-anorectal neuropathy in spinal cord injury.

Publications

Translumbar and transsacral motor-evoked potentials: a novel test for spino-anorectal neuropathy in spinal cord injury.

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