Lee Ming-Yang, Chang Guan-Liang, Chang Jia-Hao, Hung Yu-Chang, Chang Ching-Hong, Lee E-Jian
Department of Surgery & Institute of Biomedical Engineering, Neurophysiology Laboratory, Neurosurgical Service, National Cheng Kung University Medical Center & Medical School, Tainan, Taiwan.
J Trauma. 2006 Jun;60(6):1307-14. doi: 10.1097/01.ta.0000220438.61246.58.
We conducted biomechanical evaluation of the anterior plating and posterior wiring techniques for cervical spine stabilization after a course of healing in sheep.
Seventeen sheep were included, and six of which underwent sham operations (group A, n=6). The other eleven received complete C2-C3 destabilization, followed by intervertebral bone grafting and cervical stabilization either with anterior plating (group B, n=5) or posterior wiring (group C, n=6) techniques. These animals were killed 6 months later. Ligamentous spines (C1-C5) were subjected to the relevantly applied loads. The load-deformation data of the C2-C3 and C3-C4 functional units were recorded and analyzed.
At the C2-C3 functional unit, group B had the least motion ranges in flexion, lateral bending, and rotation loads than did the other two groups. Significantly smaller motion ranges of lateral bending and rotation loads were found in group B than in group C (p<0.05). Compared with group A, group C had a decreased motion range in flexion load but showed increased motion range in rotation load. Consequently, group B had superior intervertebral fusion and less osteophyte than did group C. At the C3-C4 functional unit, group B showed significantly decreased motion ranges in extension and lateral bending loads (p<0.05), while group C did not.
The results indicated that the anterior plate-stabilized spines were more stable over time than did the posterior-wired spines. This biomechanical advantage eventually resulted in superior intervertebral fusion masses in the former, although it also induced a slightly decreased motion range at the contiguous functional unit. In exclusively posterior wired-spines, the weakness for opposing rotation loads might contribute to the formation of osteophytes at the fusion functional unit. These data point out that the mode and stability of implant fixation systems greatly influence the biomechanical redistribution and bone-adaptive remodeling process during healing, which are closely related to the bone graft maturation and osteophytic formations at the fusion level and the occurrence of stiffening problems at the contiguous levels.
我们对绵羊经过一个愈合过程后颈椎稳定的前路钢板固定和后路钢丝固定技术进行了生物力学评估。
纳入17只绵羊，其中6只接受假手术（A组，n = 6）。另外11只接受C2 - C3完全失稳，随后进行椎间植骨，并采用前路钢板固定（B组，n = 5）或后路钢丝固定（C组，n = 6）技术进行颈椎稳定。6个月后处死这些动物。对韧带完整的脊柱（C1 - C5）施加相应的载荷。记录并分析C2 - C3和C3 - C4功能单元的载荷 - 变形数据。
在C2 - C3功能单元，B组在屈曲、侧弯和旋转载荷下的运动范围比其他两组最小。B组侧弯和旋转载荷的运动范围明显小于C组（p < 0.05）。与A组相比，C组在屈曲载荷下运动范围减小，但在旋转载荷下运动范围增加。因此，B组椎间融合优于C组，骨赘也更少。在C3 - C4功能单元，B组在伸展和侧弯载荷下运动范围明显减小（p < 0.05），而C组没有。
结果表明，随着时间推移，前路钢板固定的脊柱比后路钢丝固定的脊柱更稳定。这种生物力学优势最终导致前者椎间融合质量更好，尽管它也导致相邻功能单元的运动范围略有减小。在单纯后路钢丝固定的脊柱中，抵抗旋转载荷的弱点可能导致融合功能单元处骨赘的形成。这些数据指出，植入物固定系统的方式和稳定性在愈合过程中极大地影响生物力学再分布和骨适应性重塑过程，这与融合水平的骨移植成熟度和骨赘形成以及相邻水平僵硬问题的发生密切相关。
