Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital, Harvard Medical School, Newton, MA, USA; Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital, Harvard Medical School, Newton, MA, USA; Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China.
J Biomech. 2020 Jan 2;98:109418. doi: 10.1016/j.jbiomech.2019.109418. Epub 2019 Oct 15.
The in vivo intervertebral range of motion (ROM) is an important predictor for spinal disorders. While the subaxial cervical spine has been extensively studied, the motion characteristics of the occipito-atlantal (C0-1) and atlanto-axial (C1-2) cervical segments were less reported due to technical difficulties in accurate imaging of these two segments. In this study, we investigated the intervertebral ROMs of the entire cervical spine (C0-T1) during in vivo functional neck motions of asymptomatic human subjects, including maximal flexion-extension, left-right lateral bending, and left-right axial torsion, using previously validated dual fluoroscopic imaging and model registration techniques. During all neck motions, C0-1, similar to C7-T1, was substantially less mobile than other segments and always contributed less than 10% of the cervical rotations. During the axial rotation of the neck, C1-2 contributed 73.2 ± 17.3% of the cervical rotation, but each of other segments contributed less than 10% of the cervical rotation. During both lateral bending and axial torsion neck motions, regardless of primary or coupled motions, the axial torsion ROM of C1-2 was significantly greater than its lateral bending ROM (p < 0.001), whereas the opposite differences were consistently observed at subaxial segments. This study reveals that there are distinct motion patterns at upper and lower cervical segments during in vivo neck motions. The reported data could be useful for the development of new diagnosis methods of cervical pathologies and new surgical techniques that aim to restore normal cervical segmental motion.
在体椎间活动度（ROM）是脊柱疾病的重要预测指标。虽然下颈椎（C3-7）已经得到了广泛的研究，但枕-寰（C0-C1）和寰-枢（C1-C2）颈椎段的运动特征由于这两个节段的精确成像技术困难而报道较少。在这项研究中，我们使用先前验证的双荧光透视成像和模型配准技术，研究了无症状人体在进行活体颈部功能运动时整个颈椎（C0-T1）的椎间 ROM，包括最大屈伸、左右侧屈和左右轴向扭转。在所有的颈部运动中，C0-C1 与 C7-T1 相似，其活动度明显小于其他节段，且始终不到颈椎旋转的 10%。在颈部轴向旋转时，C1-C2 贡献了颈椎旋转的 73.2±17.3%，但其他节段的贡献均小于 10%。在颈部左右侧屈和轴向扭转运动中，无论主运动还是耦合运动，C1-C2 的轴向扭转 ROM 均明显大于其侧屈 ROM（p<0.001），而在下颈椎段始终观察到相反的差异。本研究揭示了活体颈部运动中，上颈椎和下颈椎节段具有明显不同的运动模式。报告的数据可能有助于开发新的颈椎病变诊断方法和旨在恢复正常颈椎节段运动的新手术技术。
