Study of reactions of the sensorimotor system in adolescents during and after surgical correction of spinal deformity

BACKGROUND: Little attention has been paid to the study of delayed sensory and motor reactions in adolescents with spinal deformities after surgical treatment.

AIM: To study the reactions of the sensorimotor system of adolescents after surgical correction of spinal deformity.

MATERIALS AND METHODS: The state of the sensory and motor spheres was analyzed in the immediate postoperative period in 21 adolescents with idiopathic scoliosis and in 13 with congenital deformities of the spine. A complex of methods involving global and stimulation electroneuromyography was used. The amplitude of motor, reflex potentials and interference electromyogram was evaluated at the maximum arbitrary tension of the lower limb muscles. Using an esthesiometer, thermal pain sensitivity in Th1–S2 dermatomes was explored. In the process of surgical correction, intraoperative neuromonitoring was performed with registration of motor evoked potentials of the lower limb muscles.

RESULTS: At the beginning of surgical intervention, high-amplitude, well-reproducible motor evoked potentials were obtained in all patients. In the group of patients with idiopathic scoliosis, compared with those with congenital deformities, smooth flow of surgery prevailed (p > 0.05) without significant changes in motor potentials relative to the baseline (p > 0.05). The number of observations of motor potentials decreased in the both groups and did not exceed 10%; the differences were not significant (p > 0.05). The study of the reactions of the sensorimotor system in the immediate postoperative period triggered an increase in the amplitude of M-responses of m. rectus femoris, m. flexor digitorum brevis, m. gastrocnemius, and a decrease in the amplitude of the total EMG of m. rectus femoris. Values of H-reflexes remained at the preoperative level. The analysis of thermal pain sensitivity demonstrated the presence of a more pronounced reaction than that of the motor component. Changes in indicators of this type of sensitivity in groups of adolescents with idiopathic and congenital scoliosis were opposite. In idiopathic scoliosis, negative dynamics of the values prevailed, while in adolescents with congenital deformities of the spine, positive dynamics prevailed. This was because the amount of correction of the main and compensatory curves of the deformity in the group with idiopathic scoliosis was 48% greater (p = 0.0004) and 51% greater (p = 0.011), respectively.

CONCLUSIONS: After surgical correction of spinal deformities in adolescents, the reactions of the sensory system of thermal pain sensitivity were more pronounced than those of the motor sphere.