[Finite element analysis of the treatment of cervical spondylotic radiculopathy with three dimensional balanced manipulation].

OBJECTIVE: To explore the biomechanical characteristics of "three-dimensional balanced manipulation" for the treatment of cervical spondylotic radiculopathy(CSR). METHODS: A CSR patient was treated with "three-dimensional balanced manipulation", and the mechanical changes during the manipulation were monitored by mechanical testing system. Using spiral CT to scan the neck of the patient to obtain DICOM data. The three-dimensional finite element model of cervical spondylotic radiculopathy was established by using Mimics software, Geographic Studio software. The "three-dimensional balance manipulation" was simulated and loaded, and the mechanical parameters of each part were replaced into the finite element model, and the finite element analysis was carried out by using ANSYS software to study the internal stress changes and displacement deformation of vertebral body and intervertebral disc under the action of "three-dimensional balance manipulation". RESULTS: The established C3-C7 finite element model of the CSR patient consisted of 5 vertebrae, 4 intervertebral discs and 3 ligaments, involving 153 471 nodes and 64 978 units. The stress of C3-C7 vertebral body was mainly located in anterior and root of C5 spinous processes, arch, vertebral arch and the combination of the two after full loading of manipulation, and the maximum stress was 17.781 MPa. The deformation sites were mainly concentrated in articular processes and anterior transverse processes of C3, superior articular processes and transverse processes of C4, articular processes of C5. The stress of C3-C7 intervertebral disc mainly distributed in the anterior part of C3, 4 intervertebral disc and the nucleus pulposus of C4, 5 and C5, 6. The displace mentextended to the middle and posterior part of C3, 4 nucleus pulposus, around the nucleus of C4, 5 and C5, 6 and anterior part of cervical intervertebral disc. CONCLUSION: The establishment of three-dimensional finite element model of C3-C7 cervical spondylotic radiculopathy can simulate the geometry and material properties of cervical spine, and also accurately reflects the biomechanical characteristics of cervical spine, verifys the internal mechanism of "three-dimensional balanced manipulation" on CSR, proves the safety and effectiveness of treatment, guides more standardized manipulation, and avoids medical accidents.