Aoyama Ryoma, Shiraishi Tateru, Yamane Junichi, Ninomiya Ken, Takahashi Yuichiro, Kitamura Kazuya, Nori Satoshi, Suzuki Satoshi
Department of Orthopedics, Tokyo Dental College Ichikawa General Hospital, Chiba, Japan.
Department of Orthopedics, Murayama Medical Center, Tokyo, Japan.
Spine Surg Relat Res. 2021 Jun 30;6(2):115-122. doi: 10.22603/ssrr.2021-0076. eCollection 2022.
The present study aimed to understand the characteristics of adjacent segment stenosis post-surgery by examining the status of adjacent segment stenosis in patients with long-term follow-up after muscle-preserving selective laminectomy (SL).
We examined 43 patients who underwent muscle-preserving SL at a single academic institution and were followed up for >10 years. The C2-C7 angle, C2-C7 sagittal vertical axis, range of motion, and C7 slope were measured using an X-ray lateral view. The anterior-posterior diameter of the spinal cord (AP of SC) and anterior-posterior diameter of the dural tube (AP of dura) at adjacent segment were measured using magnetic resonance imaging T2-weighted sagittal section. Residual space for the spinal cord at the adjacent segment (SAC) was calculated as the difference between AP of SC and AP of dura.
Four cases had cephalad adjacent segment stenosis at the last follow-up (upper stenosis (US) group), 9 cases had caudal adjacent segment stenosis ( lower stenosis (LS) group), and 30 cases had no stenosis (none (N) group). AP of SC, AP of dura, and SAC at the upper adjacent segment were significantly lower in the US group. AP of dura and SAC at the lower adjacent segment were significantly lower in the LS group. Multivariate logistic regression analysis revealed that the small AP of dura in the upper adjacent segment and small SAC in the lower adjacent segment were risk factors for developing a new stenosis.
Decompression should be considered beforehand in adjacent segments with small AP of SC and small AP of dura when performing cervical decompression.
本研究旨在通过检查保留肌肉选择性椎板切除术（SL）后长期随访患者的相邻节段狭窄情况，了解手术后相邻节段狭窄的特征。
我们检查了在单一学术机构接受保留肌肉SL手术并随访超过10年的43例患者。使用X线侧位片测量C2-C7角、C2-C7矢状垂直轴、活动范围和C7斜率。使用磁共振成像T2加权矢状位测量相邻节段脊髓前后径（SC的AP）和硬脊膜管前后径（硬脊膜的AP）。相邻节段脊髓残余空间（SAC）计算为SC的AP与硬脊膜的AP之差。
在最后一次随访时，4例出现头侧相邻节段狭窄（上狭窄（US）组），9例出现尾侧相邻节段狭窄（下狭窄（LS）组），30例无狭窄（无（N）组）。US组上相邻节段的SC的AP、硬脊膜的AP和SAC显著更低。LS组下相邻节段的硬脊膜的AP和SAC显著更低。多因素逻辑回归分析显示，上相邻节段硬脊膜的AP小和下相邻节段SAC小是发生新狭窄的危险因素。
在进行颈椎减压时，对于SC的AP小和硬脊膜的AP小的相邻节段应预先考虑减压。
