单侧小关节分级切除对腰椎稳定性影响的三维运动研究

Three Dimensional Movement Evaluation on the Effect of Unilateral Graded Facetectomy on lumbar Spinal Stability

本实验采用8具新鲜尸体腰椎功能单位,通过脊柱三维运动实验机施加最大载荷为10,ON.m的6种力偶,使脊柱产生前屈/后伸、左/右侧弯和左/右轴向旋转运动。经立体摄像计算机图像处理得到L2～3节段的运动范围(ROM),中性区(NZ)和弹性区(EZ)等参数。将完整标本测量的结果为自身对照组,然后在L2～3节段依次切除左侧小关节1/3、1/2和全部。作t检验和方差分析单侧小关节切除对腰椎三维运动的影响。结果表明:单侧小关节切除1/3后ROM增加不显著(P>0.05),不影响脊柱的稳定;小关节全切除后后伸、左侧弯和右旋的ROM增加显著(P<0.05)。小关节切除1/2后ROM虽然增加不显著,但经方差分析与小关节全切的结果无显著差异,说明小关节切除范围超过1/2将导致脊柱失稳。

The experimen t was carried out with 8 fresh humen lumbar functional spinal units. A three-dimensional movement device with the maximum loding of 10.ON.m was to produce six kinds of pure movement of force and to create six lands of movement of the lumbar spine in flection/ extension, left/right lateral bendings, left/right axial rotation. The range of movement(ROM), neutral zone(NZ)and elastic zone (EZ) of the lumbar 2-3 segments were determined by using stereophotogrammetric methods. The measurements were at first done on the intact lumbar spinal segments and data obtained were used as self-control study. Then 1/3,2/3,3/3 of the unilateral facets in the lumbar 2-3 segments were resected.At last three dimentional quantitative evaluation in analysis of the effect of graded facetectomy on the mobility of thte lumbar spinal segments was performed. The results revealed that:1.The range of motion was not affected by 1/3 facetectomy (P>0.05) 2. The range of motion increased obviously after unilateral medial and total facetectomy, and this made the lumbar spine unstable.