Abstract：Objective To investigate the biomechanical stability of general pedicle screw (monoaxial screw) and multixial screws in treatment of thoracolumbar burst fractures.Methods Six calf fresh-frozen lumbar spines (L1-L5) were selected to produce models of L3 burst fractures.The specimens were assigned to none fracture fixation group,multiaxial screw group (fixation of the fractured vertebra and upper and lower adjacent vertebral bodies with monoaxial screws,) and combined screw group (fixation of the upper adjacent vertebral body with monoaxial screws and of the fractured vertebra and lower adjacent vertebral body with multiaxia[screw).Differences in range of motion and neutral zone at level of L2-L4 at six movement directions were compared between groups.Results Range of motion and neutral zone had insignificant differences between the two groups under anterior flexion,posterior extension,lateral bending,and rotation (P ＞ 0.05),but significant difference in comparison with none fracture fixation group (P ＜ 0.01).Conclusions Combined use of multixial and monoaxial screws produces no effect on biomechanical stability of the internal fixation.Multiaxial plus monoaxial screw fixation and monoaxial screw fixation can both provide reliable biomechanical stability.
. Biomechanical stability of combined use of multiaxial and monoaxial screws in fixation of thoracolumbar burst fractures[J]. CHINESE JOURNAL OF TRAUMA, 2014, 30(2): 160-163.
