摘要
目的:探讨L5/S1和骶髂关节对腰-髂固定稳定性的影响,为腰-髂稳定性理想重建提供生物力学依据。方法:7具成年新鲜尸体L2-骨盆标本,先行L3~L5椎弓根螺钉固定,并将此结构定义为腰-髂部稳定初始状态。初始状态测试后,在同一标本上实施连续性操作如下:使用髂骨钉的L3-髂骨固定(A组)、L5/S1双侧关节突关节切除(B组)、L5/S1椎间盘切除(C组)、左侧骶髂关节切除(D组)。在MTS材料实验机上,给标本头侧分别施加600N轴向压缩和7Nm轴向扭转载荷,计算并比较各组结构压缩和扭转刚度。结果:初始状态组的压缩刚度值为(332±103)N/mm,A^D组腰-髂固定结构的压缩刚度分别为初始状态组的(122±15.5)%、(118.3±10.5)%、(81.1±7.7)%和(59.2±8.6)%。A和B组间无显著性差异(P>0.05),两组的压缩刚度均显著高于初始状态组(P<0.05);C组和D组的压缩刚度均显著低于A、B组及初始状态组(P<0.05),C组和D组间的差异也具有显著性(P<0.05)。初始状态组的扭转刚度值为(2.47±0.88)Nm/deg,A^D组固定结构的扭转刚度分别为初始状态组的(128±14.3)%、(120±12.6)%、(78.4±13.2)%和(62.9±11.3)%,A组和B组获得同等的扭转刚度(P>0.05),而且此两组的扭转刚度均显著高于初始状态、C组和D组(P<0.05),C、D组和初始状态三组彼此间的差异均具有显著性(P<0.05)。结论:L5/S1椎间盘切除和单侧骶髂关节切除均显著降低腰-髂固定结构的稳定性,在腰-髂稳定性重建中,获得脊柱前方支撑和恢复骨盆环完整性是提高腰-髂固定结构稳定性的关键。
Objectives： To explore the biomechanical effects of L5/S1 complex and sacroiliac joints on the stability of lumbo-iliae fixation construct, and to provide evidences for the rational reconstruction. Methods： Seven fresh L2-pelvic specimens harvested from donated adult cadavers were used in this study. After testing the initial state simulated by L3-L5 pedicle screw fixation, L3-iliae fixation and sequential joint resections were performed on the same specimen as follows： group A, L3-iliac fixation using bilateral iliac screws; group B, bilateral L5/S1 facetectomy; group C, LS/S1 discectomy; group D, left side sacroiliac joint resection. Biome- ehanieal testing was performed on a material testing machine under 600N compression and 7Nm torsion loading modes for construct stiffness evaluation. Results： The compressive stiffness of initial state was （332＋ 103）N/ram, group A-D obtained（122±15.5）%, （118.3±10.5）%, （81.1±7.7）% and （59.2±8.6）% of the initial com- pressive stiffness, respectively. No significant difference was detected between group A and B（P〉0.05）; further- more, the two groups showed significantly higher compressive stiffness than the initial state（P〈0.05）; group C and D exhibited lower compressive stiffness than group A, B and the initial state（P〈0.05）; there was signifi- cant difference between group C and D（P〈0.05）. The torsional stiffness of initial state was （2.47±0.88）Nm/deg. Group A-D acquired （128±14.3）%, （120±12.6）%, （78.4±13.2）% and （62.9±11.3）% of the initial torsional stiff ness, respectively. Group B obtained sufficient torsional stiffness compared to group A（P〉0.05）; both group A and B exhibited notably higher torsional stiffness than all the other three groups （P〈0.05）. Significant differ- ences were demonstrated among group C, D and initial state （P〈0.05）. Conclusions： LS/S1 discectomy and one-side sacroiliac joint resection significantly decrease the stability of lumbo-iliac fixation construct. There- fore, anterior support of spine and pelvic continuity reconstruction is important in the lumbo-iliac stability.
出处
《中国脊柱脊髓杂志》
CAS
CSCD
北大核心
2013年第9期837-841,共5页
Chinese Journal of Spine and Spinal Cord
基金
国家自然科学基金面上项目(编号:31170902)
关键词
腰骶部失稳
骶髂关节切除
髂骨钉固定
腰-髂固定
生物力学
Lumbo-sacral instability
Sacroiliac joint resection
Iliac screw fixation
Lumbo-iliac fixation
Biomechanics
