Hyun Seung-Jae, Kim Ki-Jeong, Jahng Tae-Ahn
J Neurosurg Spine. 2021 Apr 2;34(6):839-848. doi: 10.3171/2020.9.SPINE201309. Print 2021 Jun 1.
No reports have investigated how cervical reconstructive surgery affects global sagittal alignment (GSA), including the lower extremities, and health-related quality of life (HRQOL). The study was aimed at elucidating the effects of cervical reconstruction on GSA and HRQOL.
Twenty-three patients who underwent reconstructive surgery for cervical kyphosis were divided into a head-balanced group (n = 13) and a trunk-balanced group (n = 10) according to the values of the C7 plumb line, T1 slope (T1S), and pelvic incidence minus lumbar lordosis (PI-LL). Head-balanced patients are those with a negative C7 sagittal vertical axis (SVA), a larger LL than PI, and a low T1S. Trunk-balanced patients are those with a positive SVAC7, a normal PI-LL, and a normal to high T1S. Various sagittal Cobb angles, SVA, and lower-extremity alignment parameters were measured before and after surgery using whole-body stereoradiography.
Cervical malalignment was corrected to achieve cervical sagittal balance and occiput-trunk (OT) concordance (center of gravity [COG]-C7 SVA < 30 mm). Significant changes in the upper cervical spine and thoracolumbar spine were observed in the head-balanced group, but no significant change in lumbopelvic alignment was observed in the trunk-balanced group. Lower-extremity alignment did not change substantially in either group. HRQOL scores improved significantly after surgery in both groups. SVACOG-C7 and SVAC2-7 were negatively and positively correlated with the 36-Item Short-Form Health Survey physical component score and Neck Disability Index, respectively. The visual analog scale for back pain, Oswestry Disability Index, and PI-LL mismatch improved significantly in the head-balanced group after cervical reconstruction surgery.
Patients with cervical kyphosis exhibited compensatory changes in the upper cervical spine and thoracolumbar spine, instead of in the lower extremities. These compensatory mechanisms resolved reciprocally in a different fashion in the head- and trunk-balanced groups. HRQOL scores improved significantly with GSA restoration and OT concordance following cervical reconstruction.
尚无报告研究颈椎重建手术如何影响包括下肢在内的整体矢状位排列（GSA）以及健康相关生活质量（HRQOL）。本研究旨在阐明颈椎重建对GSA和HRQOL的影响。
23例行颈椎后凸重建手术的患者根据C7铅垂线、T1斜率（T1S）以及骨盆入射角减去腰椎前凸角（PI-LL）的值分为头部平衡组（n = 13）和躯干平衡组（n = 10）。头部平衡的患者是指C7矢状垂直轴（SVA）为负、腰椎前凸大于骨盆入射角且T1S较低的患者。躯干平衡的患者是指C7 SVA为正、PI-LL正常且T1S正常至高的患者。术前和术后使用全身立体放射摄影测量各种矢状位Cobb角、SVA和下肢排列参数。
颈椎排列不齐得到纠正，实现了颈椎矢状位平衡和枕部-躯干（OT）协调一致（重心[COG]-C7 SVA < 30 mm）。头部平衡组在上颈椎和胸腰椎观察到显著变化，但躯干平衡组在腰骶骨盆排列方面未观察到显著变化。两组下肢排列均未发生实质性改变。两组患者术后HRQOL评分均显著改善。COG-C7 SVA和C2-7 SVA分别与36项简短健康调查身体成分评分和颈部残疾指数呈负相关和正相关。颈椎重建手术后，头部平衡组的背痛视觉模拟量表、Oswestry残疾指数和PI-LL不匹配情况均显著改善。
颈椎后凸患者在上颈椎和胸腰椎出现代偿性变化，而非下肢。这些代偿机制在头部平衡组和躯干平衡组中以不同方式相互解决。颈椎重建后，随着GSA恢复和OT协调一致，HRQOL评分显著改善。
