胸腰段后路减压术对脊柱稳定性影响的生物力学分析

Biomechanical analysis of spinal stability after thoracolumbar posterior decompression

采用７具新鲜尸体脊柱标本（Ｔ８～Ｌ５），摹拟临床３种减压术，分别进行脊柱稳定性测试。得到脊柱各节段的运动范围（ＲＯＭ）、中性区（ＮＺ）和弹性区（ＥＺ）等参数。分析结果表明：侧前方环状次全减压术后，前屈和轴向旋转运动范围无显著性增加，但后伸及侧弯运动范围显著性加大（Ｐ＜０．０５）。侧方减压术后，损伤节段各向运动范围均显著性加大（Ｐ＜０．０５）。扩大椎板切除术后运动范围增加更为明显（Ｐ＜０．０１），脊柱严重失稳。

Seven fresh adult thoracolumbar spinal specimens (T8～L5) of human cadavers were used to evaluate the effects of three kinds of decompression at T12～L1 level on the spinal stability. Three-dimensional movements of spine were measured in each specimen with normal structure and following operations. Parameters of neutral zone (NZ),elastic zone (EZ)and range of motion(ROM)were calculated. The following results were concluded fome the present study:(1)ROMs increase slightly,while increasing significantly(P<O.05)in extension and lateral bending following the anterolateral subtotal spinal canal decompression(AD);(2)ROMs increase significantly(P<0.05) in flexion,extension,lateral bending and axial rotation following lateral decompression (LD) and extensive laminectomy (EL);(3)The ROM of thoracolumbar spine following EL is the biggest among the three kinds of decompression.Author’s address:(Department of Anatomy, the First Military Medical University,Guangzhou, 510515)