腰椎固定融合术后脊柱-骨盆矢状位序列对相邻节段退变的影响：6年以上随访研究

Effect of spinopelvic sagittal alignment on the development of adjacent segment degeneration after posterior lumbar fusion: investigation on cases with a minimum of 6 years of follow-up

中文关键词:  腰椎融合术  脊柱-骨盆矢状位  相邻节段退变

英文关键词:Lumbar fusion  Spino-pelvic sagittal alignment  Adjacent segment degeneration

中文摘要:

  【摘要】 目的：拟通过至少6年临床资料随访，探讨腰椎融合术后脊柱-骨盆矢状位序列因素对相邻节段退变（ASD）的影响。方法：回顾性分析2002年1月~2006年12月于我院骨科诊断为腰椎管狭窄症而行后路减压固定融合术患者72例，其中男33例，女39例，术时年龄55.9±9.2岁（31~71岁），术后平均随访86.8±7.5个月（72~120个月）。影像学资料包括术前腰椎MRI、正侧屈伸位X线片，末次随访腰椎MRI、全脊柱正侧位X线片；利用院内PACS系统测量骨盆入射角（PI）、骶骨倾斜角（SS）、骨盆倾斜角（PT）、腰椎前凸角（LL）、融合节段LL、剩余LL等。利用MRI与X线片判定术后ASD情况。以106例无症状中老年志愿者全脊柱X线片测量结果作为对照，比较腰椎管狭窄症患者术前及术后远期随访脊柱-骨盆矢状位序列参数，分析术后脊柱-骨盆矢状位序列的变化与ASD的相关性。结果：共50例患者（69.4%，50/72）末次随访时出现ASD；ASD组与无ASD组患者术前及末次随访骨盆矢状位参数（PI、SS、PT）与对照组比较均无显著性差异（P>0.05）。术前LL，ASD组患者（32.6°±15.4°）、无ASD组（37.3°±12.0°）显著小于对照组（49.2°±9.1°）（P<0.05）；末次随访时，无ASD组LL显著大于ASD组（42.8°±10.5° vs 36.3°±14.0°，P<0.05），但仍显著小于对照组（P<0.05）。42例未融合至S1节段的患者中31例末次随访时出现ASD，30例融合至S1节段的患者中19例出现ASD，尽管两组间ASD发生率并无显著性差异（P=0.341），但对于融合至S1组的患者，出现ASD的患者融合节段更长，LL显著减小，剩余LL显著减小。结论：①术后远期LL与ASD的发生存在相关性，充分改善LL可能会降低ASD发生率；②尽管融合至S1不是ASD发生率增加的独立危险因素，但对于融合至S1的患者，融合节段越长，术后腰椎前凸曲度越小，剩余的腰椎前凸曲度越平直，会增加ASD发生率。

英文摘要:

  【Abstract】 Objectives: To investigate the effect of postoperative spino-pelvic sagittal alignment on the development of adjacent segment degeneration(ASD) after posterior lumbar fusion in a long-term follow-up. Methods: By retrieving the medical records from January 2002 to December 2006 in our hospital, 72 patients [33 males, 39 females; mean age 55.9±9.2 years(31-71 years) at surgery] were enrolled, with mean 86.8±7.5 months(72-120 months) follow-up after surgery. Preoperative and final follow-up radiographs and MRI images were evaluated. Pelvic incidence(PI), sacral slope(SS), pelvic tilt(PT), lumbar lordosis(LL), fusion lumbar lordosis and residual lumbar lordosis were examined on radiographical images by using PACS. ASD were evaluated on MRI and X-ray radiographs. 106 asymptomatic middle-aged and elderly volunteers were recruited as control to analyze the characteristics of spinopelvic sagittal alignment after posterior lumbar fusion in a long-term follow-up. The correlation between ASD and changes of sagittal alignment were analyzed. Results: At final follow-up, degenerative changes of adjacent segment were found in 50 cases (69.4%, 50/72). There was no significant difference in pelvic sagittal parameters(PI, PT and SS) among ASD, N-ASD and control group. LL at preoperation and at final follow-up in both ASD(32.6°±15.4°) and N-ASD(37.3°±12.0°) group was significantly less than that in control group(49.2°±9.1°)(P<0.05). Significant difference between N-ASD and ASD group on final follow-up radiographs were seen for LL (42.8°±10.5° vs 36.3°±14.0°, P<0.05). Among the 42 patients who received lumbar floating fusion, 31 patients had ASD at final follow-up. Among the 30 patients received lumbosacral fusion, 19 patients had ASD at final follow-up. There was no significant difference between these two groups in ASD(P=0.341). For patients with lumbosacral fusion, ASD was seen for postoperative longer fusion segments, less total and residual lumbar lordosis. Conclusions: (1)There is correlation between the postoperative long-term lumbar lordosis and development of ASD. Obtaining appropriate lumbar lordosis is important for preventing ASD. (2)Extended fusion to the sacrum does not independently enhance the risk of ASD. But for patients with lumbosacral fusion, longer fusion segments, less total and residual lumbar lordosis will increase the risk.