Harvard University, Cambridge, USA.
J Neurosurg Spine. 2013 Apr;18(4):340-6. doi: 10.3171/2013.1.SPINE12537. Epub 2013 Feb 1.
It is not known whether adding fusion to lumbar decompression is necessary for all patients undergoing surgery for degenerative lumbar spondylolisthesis with symptomatic stenosis. Determining specific radiographic traits that might predict delayed instability following decompression surgery might guide clinical decision making regarding the utility of up-front fusion in patients with degenerative Grade I spondylolisthesis.
Patients with Grade I degenerative lumbar spondylolisthesis (3-14 mm) with symptomatic stenosis were prospectively enrolled from a single site between May 2002 and September 2009 and treated with decompressive laminectomy without fusion. Patients with mechanical back pain or with gross motion (> 3 mm) on flexion-extension lumbar radiographs were excluded. The baseline radiographic variables measured included amount of slippage, disc height, facet angle, motion at spondylolisthesis (flexion-extension), and sagittal rotation angle. Data were analyzed using multivariate forward selection stepwise logistic regression, chi-square tests, Student t-test, and ANOVA.
Forty patients were enrolled and treated with laminectomy without fusion, and all patients had complete radiographic data sets that were available for analysis. Reoperation was performed in 15 (37.5%) of 40 patients, with a mean follow-up duration of 3.6 years. Reoperation was performed for pain caused by instability at the index level in all 15 cases. Using multivariate stepwise logistic regression with a threshold p value of 0.35, motion at spondylolisthesis, disc height, and facet angle were predictors of reoperation following surgery. Facet angle > 50° was associated with a 39% rate of reoperation, disc height > 6.5 mm was associated with a 45% rate of reoperation, and motion at spondylolisthesis > 1.25 mm was associated with a 54% rate of reoperation. Patients with all 3 risk factors for instability had a 75% rate of reoperation, whereas patients with no risk factors for instability had a 0% rate of reoperation (p = 0.14).
Patients with motion at spondylolisthesis > 1.25 mm, disc height > 6.5 mm, and facet angle > 50° are more likely to experience instability following decompression surgery for Grade I lumbar spondylolisthesis. Identification of key risk factors for instability might improve patient selection for decompression without fusion surgery.
对于退行性腰椎滑脱伴症状性狭窄的患者，是否所有接受减压手术的患者都需要融合固定，目前尚不清楚。确定特定的影像学特征，这些特征可能预测减压手术后的迟发性不稳定，这可能有助于指导临床决策，即对于退行性 I 度滑脱的患者，在初次手术时是否使用融合固定。
前瞻性地纳入 2002 年 5 月至 2009 年 9 月期间在一个单中心接受减压手术的 I 度退行性腰椎滑脱（3-14mm）伴症状性狭窄的患者，这些患者接受单纯减压手术，未行融合固定。排除有机械性腰痛或屈伸位腰椎侧位片上有明显活动度（>3mm）的患者。基线影像学变量包括滑脱程度、椎间盘高度、关节突角、滑脱节段屈伸位活动度和矢状面旋转角度。使用多变量向前选择逐步逻辑回归、卡方检验、学生 t 检验和方差分析进行数据分析。
40 例患者接受了单纯减压手术，所有患者均有完整的影像学资料可供分析。40 例患者中有 15 例（37.5%）接受了翻修手术，平均随访时间为 3.6 年。所有翻修病例的手术原因均为失稳引起的疼痛。使用多变量逐步逻辑回归，阈值 p 值为 0.35，滑脱节段活动度、椎间盘高度和关节突角是术后翻修的预测因素。关节突角>50°与 39%的翻修率相关，椎间盘高度>6.5mm 与 45%的翻修率相关，滑脱节段活动度>1.25mm 与 54%的翻修率相关。有 3 个不稳定危险因素的患者翻修率为 75%，而无不稳定危险因素的患者翻修率为 0%（p=0.14）。
对于退行性腰椎滑脱 I 度患者，若减压术后滑脱节段活动度>1.25mm、椎间盘高度>6.5mm 和关节突角>50°，则更容易发生失稳。识别不稳定的关键危险因素可能有助于改善对退行性 I 度滑脱患者减压手术而不融合固定的手术选择。
