To compare the influence of classical and modified partial lateral corpectomy in vertebral instability biomechanical studies was performed. The study was carried out on fresh sectional material (9 specimens each with two spinal segments L2-L3) from dogs of non-chondrodystrophic breeds, weighing from 25 to 35 kg, who died from causes that did not cause any pathological changes in the thoracolumbar spine. Fragments of the spinal column were isolated by anatomical preparation, after which the soft tissue structures were removed as much as possible. Computed tomography was performed to exclude any structural changes in the vertebral column. Biomechanical studies were carried out on laboratorial modified UTS 110M-100 and KTS 403-100 universal testing machine. The areas of elastic and plastic deformation, maximum torque, resistance of samples in different parts of the graph, residual deformation were determined. When comparing the areas of elastic deformations in different groups, the following data were obtained. In all groups of samples, a directly proportional relationship between the load and resistance of the samples was obtained. Native vertebral specimens are the most resistant to stress, the next in strength are specimens with modified partial lateral corpectomy, the least durable ones with classical partial lateral corpectomy. The greatest resistance was exerted by native spinal specimens. The maximum torque values were (44.5 ± 1.5) N∙m. To reduce stability, the groups were arranged in the following order: the group with a classical partial lateral corpectomy [maximum value (44.5 ± 1.5) N∙m], with a modified partial lateral corpectomy [maximum value (49.5 ± 0.5) N∙m]. The difference in indicators indicates the possibility of both changing the modulus of the radius vector and the angle between the vector indicated and the direction of the acting force. The values of rotation angles at which a transition from elastic to plastic deformation was observed were also different and amounted to 22.0º ± 1.0º and 28.0º ± 1.0º degrees. The native specimens of the spine proved to be the most resistant to force applied; specimens with modified partial lateral corpectomy were less resistant than native specimens but more resistant then specimens with partial lateral corpectomy. At the same time, the samples with modified partial lateral corpectomy differed little from the native samples.

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N.A. Kozlov, A.A. Oleshkevich, B. Bhattarai, S.V. Pozyabin, "Biomechanics of vertebral column after performing modified partial lateral corpectomy," RAD Conf. Proc, vol. 4, 2020, pp. 113–117, http://doi.org/10.21175/RadProc.2020.24