术前相邻节段退变对腰椎融合术后相邻节段退变及临床疗效的影响

The effect of pre-existing degeneration at adjacent segment on postoperative adjacent segment degeneration and surgical clinical outcomes

中文关键词:  腰椎融合手术  相邻节段退变  矢状位平衡  椎管形态分级

英文关键词:Lumbar fusion  Adjacent segment degeneration  Sagittal balance  Central canal stenosis grades

中文摘要:

  【摘要】 目的：分析腰椎融合术前相邻节段已存在退变因素及对其处理方式的不同对术后相邻节段退变（adjacent segment degeneration，ASD）及临床疗效的影响。方法：纳入我院2015年7月～2017年12月手术治疗的腰椎管狭窄症患者。入选标准：责任节段为L4～S1，且责任节段的相邻节段不存在不稳定因素。术前及随访时完成腰椎MRI及腰椎正侧伸屈位X线片检查，评估责任节段及相邻节段退变状态。依据术前相邻节段椎管形态及手术处理方式的不同，将患者分为三组：A组，术前L3/4节段椎管形态为0级，手术单纯融合责任节段L4～S1；B组，术前L3/4节段椎管形态≥1级，手术单纯融合责任节段L4～S1；C组，术前L3/4节段椎管形态≥1级，手术将退变的相邻节段一并处理，L3～S1固定融合。术后进行至少1年随访。记录患者术时年龄、性别、术前身体质量指数（body mass index, BMI）、麻醉ASA分级、术后随访时间、手术相关数据，术前及随访时的Oswestry功能障碍指数（Oswestry disability index，ODI）、日本骨科协会（Japanese Orthopaedic Association scores，JOA）腰椎功能评分、腰痛及腿痛的视觉模拟评分（visual analogue scale，VAS），术前及随访时骨盆入射角（pelvic incidence，PI）、骨盆倾斜角（pelvictilt，PT）、骶骨倾斜角（sacralslope，SS）、腰椎前凸角（lumbar lordosis，LL）。根据术前及随访时的MRI和X线片上改变诊断有无ASD。结果：共有98例纳入A组，85例纳入B组，87例纳入C组。B组与C组患者年龄显著性大于A组（P<0.05），C组手术时间及术中出血量显著性大于A组与B组（P<0.05）。三组之间患者性别分布、BMI、ASA分级、随访时间、住院天数、围手术期并发症发生率均无显著性差异（P<0.05）。末次随访时A组患者21例（21/98，21.4%）出现ASD，B组53例（53/85，62.4%）出现ASD，C组42例（42/87，48.3%）出现ASD，B组、C组术后ASD的发生率显著性高于A组（P<0.01），B组与C组无显著性差异（P>0.05）；出现ASD患者的主要病理类型为椎管狭窄程度的加重；三组均无患者出现相邻节段病。末次随访时三组患者的临床功能评分均较术前有显著性改善；A组和B组的ODI改善率显著性高于C组（P<0.05），JOA和VAS评分改善率三组间无明显差异。将患者末次随访时有无术后ASD分为ASD组与非ASD组，两组术前及末次随访时的脊柱-骨盆矢状位参数无显著性差异（P>0.05）。BMI、术前相邻节段椎管形态分级是术后早期发生ASD的影响因素。结论：术前相邻节段存在退变的患者术后早期ASD的发生率较术前相邻节段无退变的患者显著性增高。将责任节段和术前相邻退变节段一并处理的患者并未获得更好的临床功能改善。术前矢状位参数不是术后发生ASD的影响因素，末次随访时矢状位平衡与术后ASD发生无关。

英文摘要:

  【Abstract】 Objectives: To analyze the effect of pre-existing adjacent segment degeneration(ASD) and its treatment on postoperative ASD and surgical clinical outcomes. Methods: Patients with lumbar spinal stenosis who received surgical treatment in Peking University Third Hospital from July 2015 to December 2017 were prospectively included. The inclusion criteria were: the responsible segment in L4-S1, and no unstable factor in adjacent segments of the responsible segment. Lumbar spinal X-ray and MRI before and after surgery were completed to evaluate the segmental degeneration. All patients were divided into three groups according to the preoperative ASD and different surgical treatments. Group A, L3/4 central canal stenosis grade is 0 before operation and the responsible segment L4-S1 simply fused. Group B, L3/4 central canal stenosis grade ≥1 before operation, and the responsible segment L4-S1 simply fused. Group C, L3/4 scentral canal stenosis grade ≥1 before operation, adjacent degenerative segment(L3/4) and responsible segment(L4-S1) fused together. There was at least 1 year follow-up. The followings were recorded: age, gender, BMI, ASA classification, follow-up time, operative data, clinical scores and measurements before operation and in the follow-up including Oswestry disability index(ODI), Japanese Orthopaedic Association Scores(JOA), visual analogue scale(VAS) for low back and leg pain, pelvic incidence(PI), pelvic tilt(PT), sacral slope(SS), and lumbar lordosis(LL). Adjacent segment degeneration was diagnosed according to preoperative and follow-up MRI and X-ray changes. Results: A total of 98 patients were enrolled in group A, 85 patients in group B, 87 patients in group C. Patients in group B and group C were significantly older than those in group A(P<0.05), and the amount of operation time and intraoperative blood loss in group C was significantly than those in group A and group B(P<0.05). There was no significant difference in gender, body mass index(BMI), ASA classification, follow-up time, hospital stays time and incidence of perioperative complications among the three groups. ASD was found in 21(21/98, 21.4%) patients in group A, 53(53/85, 62.4%) patients in group B, and 42(42/87, 48.3%) patients in group C. The incidence of ASD in group B and group C was significantly higher than that in group A(P<0.01), and there was no significant difference between group B and group C(P>0.05). The main pathological type of ASD was spinal stenosis aggravation. No patient in the three groups showed adjacent segment disease. The clinical scores in all three groups were significantly improved at the last follow-up. The ODI improvement rates of group A and group B were significantly higher than that of group C(P<0.05). There was no significant difference in JOA and VAS improvement rate between the three groups. The patients were divided into ASD group and non-ASD group at the last follow-up, and there was no significant difference of spinal-pelvic sagittal parameters between the two groups before operation and at the last follow-up(P>0.05). BMI and preoperative central canal stenosis grades were the influencing factors of adjacent segment degeneration during early follow-up. Conclusions: The incidence of early postoperative ASD in patients with preoperative ASD was significantly higher than that in patients without preoperative ASD. Surgical choice treating the responsible segment and adjacent segment together did not get better clinical outcomes. The sagittal parameters did not influence the ASD, and the sagittal balance was not related to ASD at the last follow-up.