The effect of different lumbar segmental fixation on lumbar activity and intervertebral pressure / 重庆医学

ABSTRACT

Objective To study the changes of inferior adjacent segmental after different segmental fixation ,and to analyze the accelerating mechanism of the adjacent segment degeneration .Methods Sixty sheep lumbar spine specimens (Waist 1 vertebral body-S5) with pedicle screws were collected ,according to the different fixed section ,they were divided into complete control group(not fixed) ,L6-L7 single segment fixed group ,L5-L7 short segmental fixed group ,L3-L7 long segmental fixed group .The biomechan-ical experiment was measured in the 6 N · m torque loading ,L7-S1 sacral vertebra clearance were measured in different fixed sec-tion .Results Applied in fixed ,beneath the adjacent segment in the stretch direction of angular displacement ,intervertebral disc pressure was increased significantly ,amplitude in creased with the increase of fixed range .The difference between groups was sta-tistically significant(P< 0 .05) .Conclusion After fixing spine in pedicle screws ,the longer the segmentation is fixed ,the more effect it has on subjacent segment degeneration .