Neurophysiological approach to the assessment of spinal cord function in kyphotic spinal deformity

The results of a comprehensive (clinical-radiological and neurophysiological) study performed in two clinical groups of patients (n = 64) with kyphotic spinal deformity of II–IV degree of severity of the thoracic and lumbar spine of various etiologies were analysed. With the progression of kyphotic spine deformity, the spinal cord (SC) located inside the spinal canal becomes involved in the pathological process. This period of dysfunction is preceded by a state of latent SM changes that are not detected clinically (prodromal period). The presence of neurological disorders is considered as a factor of increased risk of intra- and postoperative complications in the surgical treatment of kyphosis. Based on the registration and analysis of the parameters of somatosensory evoked potentials and motor responses during transcranial magnetic stimulation, electrophysiological signs of sensorimotor insufficiency of the SС nerve tracts were revealed, which correlate with the kyphotic arch value. The established electrophysiological criteria allow to verify the level of conductive lesion at the level of thoracic and lumbar SC segments, to determine its severity, to monitor recovery processes and to predict the functional outcome.

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