Biomechanical characteristics of lumbosacral vertebra with unidirectional axial fusion fixation system / 中国组织工程研究

ABSTRACT

BACKGROUND: It is very important to apply a new technique of minimally invasive, firm fixation and antirotation in the treatment of lumbosacral degenerative diseases. OBJECTIVE: To provide theoretical basis for clinical application by biomechanical study on the treatment of lumbosacral vertebra instability with unidirectional axial fusion internal fixation system. METHODS: Six fresh adult lumbosacral specimens were selected, and the lumbosacral motion segments (L3-S5) were intercepted and divided into the following five groups The intact normal control group (N group), bilateral isthmus fissure group (UN group), bilateral isthmus fissure + spur axial fusion internal fixation group (A group), bilateral isthmus fissure + axial screw fixation group (B group), bilateral spondylolysis + axial screw fixation alone + pedicle screw fixation on both sides group (C group). The three-dimensional motion range of flexion, lateral bending and rotation of segment L5/S1 in each group of internal fixation was compared with the axial compression resistance. RESULTS AND CONCLUSION: (1) The stability of fixed mode in A, B and C groups was better than that in the N group and the UN group under different directions of motion, and there were statistically significant differences between the groups (P 0.05). (3) In the left and right direction of rotation, the three-dimensional motion range of rotation in the A group was significantly reduced compared with that in the B group, and there was no significant difference between A group and C group (P > 0.05). (4) The lumbosacral vertebra unidirectional axial fusion internal fixation system has good biomechanical stability and strong anti-rotation ability, and is expected to be used in clinic.