Aoyama Ryoma, Shiraishi Tateru, Yamane Junichi, Ninomiya Ken, Kitamura Kazuya, Nori Satoshi, Suzuki Satoshi
Department of Orthopaedics, Tokyo Dental College Ichikawa General Hospital, Chiba, Japan.
Department of Orthopaedics, Murayama Medical Center, Tokyo, Japan.
Spine Surg Relat Res. 2018 Aug 25;3(2):136-140. doi: 10.22603/ssrr.2018-0034. eCollection 2019 Apr 27.
The purpose of this study was to elucidate the duration for which the dural tube continues to expand after muscle-preserving cervical laminectomy and the extent to which the expansion affects surgical outcomes.
We analyzed 83 patients with cervical myelopathy who underwent muscle-preserving selective laminectomy of three consecutive laminae between C4 and C6. On the lateral radiographs, parameters considered were C2-7 Cobb angles, range of flexion-extension neck motions, and C2-7 sagittal vertical axis. Neck alignment was classified into four types with lateral radiographs. Anteroposterior (AP) diameter of the dural tube was measured at mid-level of the C5 vertebral body on T2 sagittal image. Expansion ratio (ER) was defined as the extent of expansion at a particular time divided by the final extent of expansion of the dural tube diameter. Operative outcomes were examined using the Japanese Orthopaedic Association scores.
The mean age was 62.3 years, and the mean follow-up period was 2 years and 9 months. AP diameter of the dural tube had been expanding until 1-year after surgery. ER in cases with kyphosis was lower at 6 months than that in cases without kyphosis, indicating that the speed of dural expansion was slower in cases with kyphosis. There was no correlation between the extent of expansion of the dural tube and neurological recovery.
The dural tube continued to expand for approximately 1-year after surgery. The dural tube of patients with kyphosis slowly expanded possibly because of the hardness of the dura mater. A small extent of dural expansion does not necessarily indicate bad surgical outcomes.
本研究的目的是阐明保留肌肉的颈椎椎板切除术后硬脊膜管持续扩张的时间以及扩张程度对手术结果的影响。
我们分析了83例患有颈椎病的患者，他们接受了C4至C6之间连续三个椎板的保留肌肉的选择性椎板切除术。在侧位X线片上，考虑的参数有C2 - 7 Cobb角、颈部屈伸活动范围以及C2 - 7矢状垂直轴。通过侧位X线片将颈椎排列分为四种类型。在T2矢状位图像上于C5椎体中部测量硬脊膜管的前后径。扩张率（ER）定义为特定时间的扩张程度除以硬脊膜管直径的最终扩张程度。使用日本骨科协会评分来检查手术结果。
平均年龄为62.3岁，平均随访期为2年9个月。硬脊膜管的前后径在术后1年一直处于扩张状态。后凸畸形患者在6个月时的扩张率低于无后凸畸形患者，表明后凸畸形患者硬脊膜扩张速度较慢。硬脊膜管的扩张程度与神经功能恢复之间没有相关性。
术后硬脊膜管持续扩张约1年。后凸畸形患者的硬脊膜管扩张缓慢可能是由于硬脊膜的硬度。硬脊膜扩张程度小并不一定意味着手术结果不佳。
