3D modeling and biomechanical study of the lumbar spine in children with congenital scoliosis after surgical treatment

In domestic and foreign publications, there are no biomechanical studies of the correction of the structures of the musculoskeletal system in patients of early childhood. In addition to the frequency of congenital deformities of the spine, the relevance of the work is due to the progressive nature of the course of the disease, the severity and rigidity of deformities, as well as the formation of compensatory curvature arcs. The most frequent complications associated with metal structures are their destabilization due to endofixator fatigue fractures, bone resorption around screws, destruction of the cortical tissue of the arch roots. The construction of computer three-dimensional models is based on the data of computed tomography of patients with congenital deformity of the lumbar spine. Computer geometric models include the bodies of four vertebrae. Models are built in the computer programs Mimics Medical and 3-matic Medical, then exported to the SolidWorks software package. It assembles all the individual elements, and adds: ligamentous apparatus, intervertebral discs, and metal structures. Bone structures are schematized by two homogeneous isotropic layers: cortical and spongy. A method for studying the stress-strain state in the lumbar spine-endofixator system has been developed for different motor modes and different bone resorption around the screws. Biomechanical studies of the state of the lumbar spine in a three-year-old patient after surgery with an installed endofixator were carried out.

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