Ito Kenyu, Yukawa Yasutsugu, Ito Keigo, Machino Masaaki, Kanbara Shunske, Nakashima Hiroaki, Hida Tetsuro, Ishiguro Naoki, Imagama Shiro, Kato Fumihiko
Department of Orthopaedic Surgery, Chubu Rosai Hospital, 1-10-6 Koumei Minato-ward, Nagoya-city, Aichi 444-8530, Japan; Department of Orthopaedic Surgery, Nagoya University Hospital, Graduate School of Medicine, 65 Tsurumai Showa-ward, Nagoya-city, Aichi 466-8550, Japan.
Department of Orthopaedic Surgery, Chubu Rosai Hospital, 1-10-6 Koumei Minato-ward, Nagoya-city, Aichi 444-8530, Japan.
Spine J. 2015 Mar 1;15(3):461-6. doi: 10.1016/j.spinee.2014.10.001. Epub 2014 Oct 14.
Dynamic changes in the spinal cord cross-sectional area due to cervical ossification of the posterior longitudinal ligament (C-OPLL) are unknown, but dynamic multidetector-row computed tomography (MDCT) may be a useful tool.
The purpose of this study was to evaluate the influence of dynamic factors on the spinal cord in patients with C-OPLL using MDCT during flexion and extension after myelography.
STUDY DESIGN/SETTING: This was a prospective cohort study.
Participants included 107 prospectively enrolled consecutive patients with C-OPLL and myelopathy.
The outcome measure was the extension/flexion ratio at the spinal cord cross-sectional area at the most stenotic cervical level (SCASL).
Dynamic MDCT was performed, and the SCASL was measured. Patients were divided into the kyphosis group or lordosis group according to C2-C7 alignment. They were divided further into the K-line (-) group or K-line (+) group. The Japanese Orthopedic Association (JOA) score was used to determine myelopathy severity.
All patients with C-OPLL had myelopathy, with a mean JOA score of 10.7 and mean disease duration of 16.7 months. The average extension/flexion ratio at all disc levels was less than 100%, suggesting that the spinal cord was compressed more during extension. In the kyphosis group, the spinal cord was compressed slightly more during flexion than during extension. In the K-line (-) group, the spinal cord was compressed more during flexion, although C2-C7 alignment was slightly lordotic on average. Large changes in the spinal cord cross-sectional area during extension-flexion and disease duration significantly influenced the severity of myelopathy.
Dynamic MDCT was useful for evaluating dynamic changes in the spinal cord. At the most stenotic level, the spinal cord became narrower during extension at all disc levels. In the kyphosis group and K-line (-) group, it became narrower during flexion. Cervical flexion may induce greater spinal cord compression in patients with kyphosis and K-line (-).
由于颈椎后纵韧带骨化（C-OPLL）导致的脊髓横截面积动态变化尚不清楚，但动态多排螺旋计算机断层扫描（MDCT）可能是一种有用的工具。
本研究的目的是使用MDCT在脊髓造影后的屈伸过程中评估动态因素对C-OPLL患者脊髓的影响。
研究设计/地点：这是一项前瞻性队列研究。
参与者包括107例前瞻性纳入的连续性C-OPLL和脊髓病患者。
观察指标是最狭窄颈椎节段脊髓横截面积的伸展/屈曲比（SCASL）。
进行动态MDCT并测量SCASL。根据C2-C7对线情况将患者分为后凸组或前凸组。再进一步分为K线（-）组或K线（+）组。采用日本骨科协会（JOA）评分来确定脊髓病的严重程度。
所有C-OPLL患者均患有脊髓病，平均JOA评分为10.7分，平均病程为16.7个月。所有椎间盘节段的平均伸展/屈曲比均小于100%，表明脊髓在伸展时受压更严重。在后凸组中，脊髓在屈曲时比伸展时受压略多。在K线（-）组中，尽管C2-C7平均对线略呈前凸，但脊髓在屈曲时受压更严重。伸展-屈曲过程中脊髓横截面积的大幅变化和病程显著影响脊髓病的严重程度。
动态MDCT有助于评估脊髓的动态变化。在最狭窄节段，所有椎间盘节段的脊髓在伸展时变窄。在后凸组和K线（-）组中，脊髓在屈曲时变窄。颈椎屈曲可能在患有后凸和K线（-）的患者中导致更大的脊髓压迫。
