Comparative analysis of the effect of decompression techniques on the range of motion of the vertebrae in the thoracolumbar spine in dogs

Abstract

The work was carried out with the aim of conducting a comparative analysis of the effect of hemilaminectomy and mini-hemilaminectomy on the range of motion of the vertebrae in the thoracolumbar spine in dogs and to establish a correlation between changes in the range of motion of the vertebrae at the site of decompression and in adjacent spinal motion segments with the incidence of relapses of intervertebral disc extrusions and the emergence of a «domino effect». The research was carried out in 2023 on the basis of the Department of Veterinary Surgery of the Federal State Budgetary Educational Institution of Higher Education MGAVMiB – MBA named after K. I. Scriabin. The object of the study was sectioned material from dogs of chondrodystrophic breeds (n=5), the subject of the study was the thoracolumbar section of the spinal column Th10-S1. The range of motion of the vertebrae in each individual spinal motion segment was studied by comparing their positions in the neutral position, during flexion and during extension: in the native state – 3 samples, in the native state and after hemilaminectomy at the Th13-L1 level – 1 sample, in in the native state and after performing a mini-hemilaminectomy at the Th13-L1 level – 1 sample. At the site where the decompression technique was applied, the range of Th13-L1 vertebral motion increased by 51,66 % with hemilaminectomy and decreased by 0,76 % with mini-hemilaminectomy (the difference is statistically significant, p=0.001). In the adjacent spinal motion segment Th12– Th13, the range of vertebral motion increased by 22,25 % with hemilaminectomy and by 8,39 % with mini-hemilaminectomy (the difference is statistically significant, p=0,01). The correlation coefficient between the frequency of relapses of extrusions and changes in the range of motion of the vertebrae at the site of decompression is 0,71, which indicates a relationship between the average tightness between the analyzed indicators. The correlation coefficient for the risk of the «domino effect » and changes in the range of motion of the vertebrae in spinal motion segments adjacent to the site of decompression is 0,77, which indicates a strong correlation between the analyzed indicators.