颈椎后路减压术后脊髓后移的临床意义

Clinical significance of posterior spinal cord shifting after open-door laminoplasty

目的探讨颈椎后路全椎板减压和椎管成形术后脊髓后移对多节段脊髓型颈椎病的临床意义。方法回顾性分析2004年6月至2007年9月65例多节段脊髓型颈椎病患者的病例资料，男41例，女24例；年龄39-75岁，平均56_3岁。33例采用颈后路选择性椎板切除术（切除组），32例采用颈后路单开门椎管成形术（开门组）。两组患者术前日本矫形骨科学会（Japanese Orthopaedics Association，JOA）评分、颈椎曲度指数的差异无统计学意义。术后1年，评估两组的脊髓后移距离、神经功能（JOA评分）改善率、颈椎曲度指数丢失及轴性症状评分。结果全部病例均获得26-47个月的随访，平均34个月。切除组术后1年脊髓后移距离（1．4±0．6）mm，开门组（3．3±1．2）nlm，差异有统计学意义；切除组JOA评分改善率60．5％±21．3％，开门组61．1％±17．9％，差异无统计学意义；切除组颈椎曲度指数丢失3．3％±1．7％，开门组3．1％±2．4％，差异无统计学意义；切除组18．2％（6／33）的患者术后有明显轴性症状，开门组为33.3％（10／30），两组轴性症状临床评分的差异有统计学意义。结论选择性椎板切除术后脊髓后移距离小于单开门椎管成形术。脊髓后移程度与术后功能恢复程度及颈椎曲度无关，而与轴性症状有关。

Objective To investigate the clinical significance of posterior spinal cord shifting after two different types of laminoplasty for multilevel cervical myelopathy. Methods From June 2004 to September 2007, 65 patients with cervical spondylotic myelopathy were reviewed in this study, including 41 males and 24 females with an average age was 56.3 years （range, 39-75）. Among them, 33 patients underwent selective laminoplasty and 32 patients underwent open-door laminoplasty. There were no significant differences of preoperative JOA scores and cervical curvature index between two groups. After one year follow - up, the posterior shifting of spinal cord, Japanese Orthopaedics Association （JOA） recovery rate, loss of curvature index and axial symptom for each patient were calculated. Results All cases were fallowed up for average 34 months （range, 26-47）. There was significant difference of the postoperative posterior shifting between the two groups, which was （1.4±0.6） mm in selective laminoplasty group and （3.3±1.2） mm in opendoor laminoplasty group, respectively. The average JOA recovery rate was 60.5%±21.3% and 61.1%±17.9% in selective laminoplasty and open-door laminoplasty group, respectively. There was no significant difference of JOA recovery rate between the two groups. Loss of cervical curvature indices was 3.3%±1.7% and 3.1%± 2.4% in selective laminoplasty and open-door laminoplasty group, respectively, with no significant difference between the two groups. The rate of patients with evident axial symptoms was 18.2% and 33.3% in selective laminoplasty group and open-door laminoplasty group, and the difference of the scores of cervical axial symptom was statistically significant. Conclusion The degree of the postoperative posterior shifting of the spinal cord in open-door laminoplasty group was greater than that in selective laminoplasty group. The poste- rior shifting of the spinal is correlated with cord,axial symptom but not the recovery rate and curvature index.