Biomechanical properties of lower anterior vertebral pedicle screw system and its effects on osteoporotic vertebral stability / 中国组织工程研究

ABSTRACT

BACKGROUND:Although the traditional surgical treatment can improve the symptoms of patients with senile osteoporotic vertebral fracture, the treatment easily produces bone graft fusion failure and pseudoarticulation formation and affects clinical effects. OBJECTIVE:To investigate biomechanical properties of anterior cervical pedicle screw and the effects on osteoporotic vertebral stability. METHODS:A total of 16 fresh cadaver cervical specimens contained 64 motion segments (C3-4, C4-5, C5-6 and C6-7). The 64 segments by the way of implantation were randomly divided into ordinary anterior locking screw fixation group and lower anterior vertebral pedicle screw system group (32 segments per group). The mechanical properties were determined on the biomechanical testing machine for each group. RESULTS AND CONCLUSION:(1) BiomechanicsCompared with the ordinary anterior locking screw fixation group, the maximum pul-out strength, screw path length, postoperative vertebral column height, the maximum surface strain, strain maximum and the range of maximum values were increased in the lower anterior vertebral pedicle screw system group (P<0.05). (2) Results suggest that compared with the ordinary anterior locking screw fixation group, lower cervical anterior pedicle screw required larger extraction force and was more stable for osteoporotic vertebrae.