腰椎融合术后相邻节段退变的相关因素分析

Correlative factors for adjacent segment degeneration after lumbar spinal fusion

中文关键词:  腰椎融合术  相邻节段退变  骨盆入射角

英文关键词:Lumbar fusion  Adjacent segment degeneration  Pelvic incidence

中文摘要:

  【摘要】 目的：探讨腰椎融合术后影响相邻节段退变（adjacent segment degeneration，ASD）的因素。方法：回顾性分析北京大学第三医院骨科2009年1月~2011年1月因腰椎管狭窄症行腰椎后路融合手术患者109例，其中男39例，女70例，年龄24~79岁，平均54岁。门诊随访2~4年，平均3.4年。测量术前融合节段角度（fusion angle，FA）、融合节段头尾端相邻节段角度（proximal angle，PA；distal angle，DA）、腰椎前凸角（lumbar lordosis，LL）、骶骨倾斜角（sacral slope，SS）、骨盆入射角（pelvic incidence，PI）、融合与非融合相邻节段移位距离（slip distance，SD）等参数。以术后2年时站立位X线片相邻节段滑移≥3mm定义为ASD，将患者分为退变组（A组）和非退变组（B组）。同时记录两组患者性别、年龄、骨密度、融合节段数等。采用t检验及χ2检验比较两组间各指标的差异，应用Logistic回归分析ASD的影响因素。结果：A组18例（16.5%），B组91例（83.5%）。发生ASD患者均为融合节段头端相邻节段退变。A组患者术前LL为29.8°±12.5°，B组为32.4°±11.2°；A组SS为31.5°±12.1°，B组为37.4°±13.4°；A组FA为18.3°±9.0°，B组为14.8°±10.5°； A组PA为6.8°±3.2°，B组为7.2°±5.2°；A组PI为42.3°±9.8°，B组为49.9°±9.8°；两组比较均有统计学差异（P＜0.05）。两组患者性别、年龄、骨密度、融合节段数及DA等均无统计学差异（P＞0.05）。Logistic回归分析显示PI与ASD发生率有显著相关性（P＜0.05），SS、LL、FA、PA与ASD发生率无相关性（P＞0.05）。结论：在腰椎融合术后影响ASD的诸多因素中，过小的PI值可能是导致ASD的重要因素。

英文摘要:

  【Abstract】 Objectives: To explore risk factors associating with adjacent segmental degenerations after lumbar fusion surgery. Methods: A retrospective analysis was performed on 109 cases of lumbar stenosis undergoing lumbar posterior decompression, pedicle screw fixation and fusion in orthopedic department of Peking University Third Hospital from January 2009 to January 2011. These cases included 39 males and 70 females with ages ranging from 24 to 79 years(average, 54 years). All of them were followed up by a 2- to 4-year(average, 3.4 years) outpatient questionnaire. Measurement included peroperative angles of fusion segment(FA), proximal and distal adjacent angles of fusion segments(PA, DA), lumbar lordosis(LL), sacral slope(SS), pelvic incidence(PI) in pre-operation, and slip distance（SD） between fusion and non-fusion segments. Adjacent segment rdiograpfic degeneration was defined as adjacent segmental slip of 3mm or more on standing X-ray at post-operative 24 months. All patients were categorized into degenerative group(group A) and non-degenerative group(group B). Gender, age, bone mineral density, number of fusion segments were also recorded. The comparative results between two groups were analyzed by t-test and χ2 -test. Risk factors of adjacent segment radiographic degeneration were analyzed by using Logistic regression. Results: There were 18 cases(16.5%) in group A and 91 cases(83.5%) in group B developing ASD, and all ASD occurred at proximal adjacent segments. Preoperative results were as follows: LL for group A and B was 29.8°±12.5° and 32.4°±11.2°; SS for group A and B was 31.5°±12.1° and 37.4°±13.4°; FA for group A and B was 18.3°±9.0° and 14.8°±10.5°; PA for group A and B was 6.8°±3.2° and 7.2°±5.2°, which all showed significant differences between two groups(P＜0.05). PI of group A(42.3°±9.8°) was significantly lower than that of group B(49.9°±9.8°)(P＜0.05). Gender, age, bone mineral density, number of fusion segments and DA were not associated with ASD(P＞0.05). Logistic regression analysis showed significant correlation with PI and incidence of ASD(P＜0.05), but no correlation between SS, LL, FA, PA and incidence of ASD（P＞0.05）. Conclusions: Of the risk factors inducing ASD, low PI may be one of the important factors.