Peng Y J, Wang Y, Ma W H, Shi K R, Xu D L, Li H J, Zhou S Y, Zhao X C
Medical School of Ningbo University, Ningbo 315211, China.
Department of Spinal Surgery, Ningbo Sixth Hospital Affiliated to Ningbo University Medical School, Ningbo 315040, China.
Zhonghua Yi Xue Za Zhi. 2021 Aug 3;101(29):2299-2303. doi: 10.3760/cma.j.cn112137-20210204-00355.
To analyze the feasibility of anterior occipitocervical fusion biomechanical characteristic of craniovertebral reconstruction by anterior occipital condyle screw plate system. Six cervical vertebra specimens including 4 males and 2 females were enrolled, whose mean age of death was (49.3±7.5) years. The normal models were established by soft tissue dissection, and the instability models were established by destroy bone and ligament structure including, anterior arch of the atlas, part of the lateral mass of the atlas, the odontoid process, the odontoid apical ligament, the pterygoid ligament, the transverse ligament of the atlas the joint capsule. The clivus screw fixation models were established by anterior clivus screw fixation, and then those models were performed by anterior occipital condyle screw fixation. All four groups were loaded with a 1.5 N·m continuous pure force in flexion-extension, lateral bending, and axial rotation. Then measured the range of motion of specimen C-C and C-C. And the pull-out force test was conducted to compare the effects of unicortical and bicortical fixation on the pull-out force of screws. In the C-C segment, the range of motion in flexion-extension (forward and posterior), lateral bending and axial rotation in the clivus group was 6.46°±0.85°, 5.14°±0.76°, 2.73°±0.36°, 1.12°±0.41°, respectively; and it was 5.92°±0.90°, 4.16°±1.06°, 2.86°±0.50°, 1.05°±0.27°, respectively in the occipital condyle group. As for C-C segment, the range of motion in the clivus group was 9.55°±1.99°, 10.46°±2.03°, 6.90°±1.29°, 13.51°±1.37°, respectively; and it was 8.14°±1.38°, 9.53°±1.55°, 4.75°±1.06°, 7.90°±1.68°, respectively, in the occipital condyle group. The ranges of motion in the occipital condyle group were significantly lower than clivus group (all <0.05). The maximum pull out force by bicortical fixation was significantly better than unicortical fixation ((439±33) N vs (408±28) N, <0.05). The anterior occipital condyle screw plate system provides better stability especially in anti-bending and anti-rotation than the anterior clival screw fixation.
分析前路枕髁螺钉钢板系统进行颅颈重建的前路枕颈融合生物力学特性的可行性。纳入6例颈椎标本，其中男性4例，女性2例，平均死亡年龄为（49.3±7.5）岁。通过软组织解剖建立正常模型，通过破坏包括寰椎前弓、部分寰椎侧块、齿突、齿突尖韧带、翼状韧带、寰椎横韧带、关节囊在内的骨和韧带结构建立不稳定模型。通过斜坡螺钉固定建立斜坡螺钉固定模型，然后对这些模型进行前路枕髁螺钉固定。所有四组均在屈伸、侧弯和轴向旋转时施加1.5 N·m的连续纯力加载。然后测量标本C-C和C-C的活动范围。并进行拔出力测试，比较单皮质和双皮质固定对螺钉拔出力的影响。在C-C节段，斜坡组屈伸（前后）、侧弯和轴向旋转的活动范围分别为6.46°±0.85°、5.14°±0.76°、2.73°±0.36°、1.12°±0.41°；枕髁组分别为5.92°±0.90°、4.16°±1.
