后路枕骨髁螺钉内固定系统的生物力学研究

Biomechanical study of posterior occipital condylar screw internal fixation system

中文关键词:  枕颈融合  枕骨髁螺钉  生物力学

英文关键词:Occipitocervical fusion  Occipital condyle screws  Biomechanics

中文摘要:

  【摘要】 目的：通过对后路枕骨髁螺钉内固定系统治疗枕颈部不稳的生物力学研究，为其临床应用提供理论依据。方法：选取6具年龄32~55岁，身高155～180cm的颈椎尸体标本，不做手术处理建立正常模型，切断标本的寰椎横韧带、齿状突尖韧带、翼状韧带，制作枕颈不稳模型，枕骨髁螺钉的置钉固定建立枕骨髁螺钉内固定模型，分别给予三个模型枕骨1.5N·m的屈伸、侧弯、旋转力矩，测量标本C0~C1与C0~C2的前屈后伸、侧弯、旋转的运动范围（range of motion，ROM），分析比较正常模型、失稳模型及内固定模型的运动范围改变，评价枕骨髁螺钉内固定系统的生物力学有效性。结果：在C0~C1节段上，正常模型的前屈、后伸、侧弯、旋转活动度分别为：14.13°±0.71°、7.60°±0.43°、3.77°±0.27°、5.42°±0.44°，失稳模型的活动度分别为23.57°±2.26°、11.96°±1.44°、5.21°±0.29°、7.13°±0.67°，枕骨髁螺钉内固定模型的活动度分别为7.53°±0.77°、3.79°±0.64°、2.56°±0.34°、0.89°±0.31°；而在C0~C2节段上，正常模型的前屈、后伸、侧弯、旋转活动度分别为：19.72°±0.71°、17.62°±0.97°、7.55°±0.51°、51.46°±3.11°，失稳模型的活动度分别为30.57°±2.32°、23.85°±0.91°、9.37°±0.55°、68.91°±6.25°，枕骨髁螺钉内固定模型的活动度分别为11.30°±0.66°、9.19°±0.63°、5.12°±0.59°、7.39°±0.76°。失稳模型的活动度大于正常模型，正常模型的活动度大于固定模型。结论：枕骨髁螺钉内固定系统能有效减少枕颈部的前屈、后伸、侧弯、旋转的运动范围，充分证明了该固定技术具有可靠的生物力学稳定性。

英文摘要:

  【Abstract】 Objectives: To provide experimental basis for the occipital condyle screw technique through a biomechanical analysis. Methods: The normal model, instability model and occipital condyle screw fixation model were built respectively, 6 fresh craniocervical(C0-C4) specimens were screened by CT scan. 1.5 N·m torque was added at flexion, extension, lateral flexion and rotation direction, and then their relative range of motion(ROM) was measured. Finally, the validity of the occipital condylar screw fixation techniques was evaluated by comparing their range of motion(ROM). Results: The ROMs(C0-C1) of the normal model were 14.13°±0.71°, 7.60°±0.43°, 3.77°±0.27°, 5.42°±0.44° in flexion, extension, lateral bending and rotation, respectively. The ROMs of instability model were 23.57°±2.26°, 11.96°±1.44°, 5.21°±0.29°, 7.13°±0.67°, and those of the occipital condyle screw fixation model were 7.53°±0.77°, 3.79°±0.64°, 2.56°±0.34°, 0.89°±0.31°.Similarly in the C0-C2 segments, the ROMs of the normal model were 19.72°±0.71°, 17.62°±0.97°, 7.55°±0.51°, 51.46°±3.11° respectively, the instability model′s were 30.57°±2.32°, 23.85°±0.91°, 9.37°±0.55°, 68.91°±6.25°, and those of the occipital condyle screw fixation model were 11.30°±0.66°, 9.19°±0.63°, 5.12°±0.59°, 7.39°±0.76°. The ROM of the instability model is largest and the normal model is larger than the occipital condyle screw fixation model. Conclusions: The occipital condyle screw fixation technology can reduce the ROM(C0-C1, C0-C2), which is reliable in clinical practice.