Piontkovskyі V. Transpedicular fixing at a lumbar spine osteochondrosis

Object: surgical treatment of degenerative diseases of lumbar spine. Aim: to improve results of operative treatment of lumbar spine osteochondrosis with a use of transpedicular fixing by creating and clinical introduction of new constructive solutions. Methods: clinical, radiological, mathematical modeling, experimental, statistic. For the first time on basis of clinical and radiological researches, experimental modeling on the laboratory animals, mathematical modeling with a use of finite element method it was determined that introduction of transpedicular screws into the intervertebral disc subchondral area provokes an appearance and progressing of dystrophic and degenerative changes of cranial adjacent intervertebral disc. First new parametric approach to the study of an influence of location parameters and fixing device orientation on characteristics of the spine stability and traumatic was created during mathematical and experimental modeling of the reconstructive surgery. Developed parametric model of biomechanical system (spinal segments with fixing device) enables to define a dependence of integral characteristics of mode of deformation from alterable parameters. New rated experimental technology of researches for construction of authentic high-precision estimated models of biomechanical system elements was developed. New polyaxial screw for transpedicular fixing and guidelines for efficient choice of variable parameters of fixing elements and binding at surgery were worked out. The boundary value of variable parameters was determiner. On approximation of its traumatization after the screws use increases dramatically. The change of screws length and screw mounting angles allows take into account some individual features at the operative treatment of patients having degenerative diseases of the lumbar spine. First during prospective clinical and radiological investigation it was shown that the use of new scientific knowledge, developments and improvement of technology of transpedicular fixing allows to increase effectiveness of surgery treatment of lumbar spine degenerative diseases appreciably. Notable decrease a number of events of false introducing screws by following recommendation for efficient choice of alterable fixing elements parameters (recommended angle of cephalad-caudal rejection of screw is 0° or 5–7° but not more than 7°, recommended distance from threaded screw part to superior end-plate and frontal vertebra part ? 5 mm); decrease the traumatic changes and the risk of trophic abnormalities progress in adjacent end-plates and intervertebral discs, decrease appearance of bone resorption near the screws, the slackening or fracture of device elements. The use of developed polyaxial screw allows decrease time of surgery. Thereby it allows decrease intraoperative blood loss at the expense of the facilitation of rigging device, avoid uncontrolled changes of lumbar lordosis size and ensure spondylarthrosis progress in adjacent segments, ensure proper screws introducing and sure fixing at hyperlordosis, spondylolisthesis, degenerative scoliosis. Adoption of received new scientific knowledge and improved transpedicular fixing technology into clinical practice allows improve the results of surgical treatment of patients with a degenerative diseases of lumbar spine. New constructive solutions of transpedicular fixing were introduced into clinical practice Public Institution “Sytenko Institute of Spine and Joint Pathology, Ukrainian Academy of Medical Sciences”; Town Clinical Hospital of Emergency, Kyiv; Regional Clinical Hospital, Ivano-Frankivsk; Town Hospital, Khmelnitski; Regional Municipal Institution “Hospital of Emergency”, Chernivtsi. Traumatology and orthopaedy.