术中腰骶部水平化改善退变性腰椎侧凸术后冠状面平衡

Lumbosacral-levelization during surgery reduce the risk of post-operative coronal imbalance in degenerative lumbar scoliosis after long spinal fusion

目的探讨冠状面失平衡C型（C7铅垂线偏向腰弯凸侧〉3 cm）成人退变性腰椎侧凸患者中应用腰骶部代偿弯凸侧经椎间孔椎间融合术（transforaminal lumbar interbody fusion，TLIF）对冠状面平衡维持的影响。方法回顾性分析2006年6月至2015年6月间接受矫形手术治疗的成人退变性腰椎侧凸患者140例，其中后路长节段（融合节段≥5）伴冠状面失衡C型患者共27例（女25例，男2例）。所有患者依据是否行腰骶部（L4，5或L5S1）TLIF术分为两组，对比两组患者术后腰骶部水平化角度、术后冠状面平衡维持状况及患者术后融合节段融合情况，并记录植入物相关并发症。所有患者术前、术后及末次随访时应用健康调查问卷简化版（SF-36）、Oswestry功能障碍指数问卷表（Oswestry disability index，ODI）、疼痛视觉模拟评分（visual analogue scale，VAS）评估临床疗效。结果术后平均随访51个月（24-120个月）。TLIF组纳入11例患者，无TLIF组纳入16例患者，两组患者的术前、术后及末次随访腰弯Cobb角及矢状面平衡指标（sagittal vertical axis, SVA）均无明显差异。术前两组患者均存在腰骶部（L4，5或L5S1）倾斜，下端融合椎（last instrumented vertebra，LIV）为L5时L5上终板与水平线夹角（a1）为8.2°±4.0°；LIV为S1时S1上终板与水平线夹角（a2）为12.1°±5.6°；LIV为S2时S1上终板与水平线夹角（a2）为11.4°±5.5°。术后即刻TLIF组较无TLIF组腰骶部水平化程度明显增加（LIV为L5，2.1°vs. 8.1°；LIV为S1，3.8° vs.8.1°；LIV为S2，3.1°vs. 8.7°），末次随访时TLIF组腰骶部水平化维持良好。TLIF组术后即刻冠状面平衡距离（coronal balance distance，CBD）与无TLIF组未见明显差异[（1.6±1.1）cm与（1.8±1.0）cm]；TLIF组末次随访时CBD明显小于无TLIF组[（1.8±0.9）cm与（2.5±1.5）cm]。末次随访时TLIF组腰骶部融合率（L4，5或L5S1）高于无TLIF组（100%，11/11与93.75%，15/16）。TLIF组SF-36生理总分（PCS）、ODI在末次随访时优于无TLIF组，但差异无统计学意义。结论在伴有冠状面失平衡C型成人退变性脊柱侧凸患者中应用腰骶部代偿弯凸侧TLIF技术结合后路矫形内固定术可以术中实现腰骶部水平化，进而在达到侧凸矫形的同时纠正冠状面失平衡，并有利于远期随访中冠状面平衡的维持。

Objective To evaluate the postoperative coronal balance and clinical outcomes of transforaminal lumbar in- terbody fusion （TLIF） at convex side utilized in adult degenerative lumbar scoliosis （DLS） patients with coronal imbalance type C （CTPL shifted to the convex side for more than 3 cm）. Methods All of 27 patients （2 males and 25 females） receiving posterior long spinal segment fusion surgery （5 or more segments involved） from June 2006 to June 2015 were retrospectively reviewed. The average age of the cohort was （62.11± 8.22） years, （range, 50-76 years）. 11 patients underwent to a transforaminal lumbar interbody fusion （TLIF） at convex side of fractional curve procedure, while 16 had only long fusion. The coronal parameters including Cobb angle and distance between C7 plumb line and center sacral vertical line （CTPL-CSVL）, as well as oblique angle of L4, L5, S1 and fusion level of L4.5, L5S1 were measured preoperatively, postoperatively and last follow up. The Short Form-36 Health Survey （SF-36）, Oswestry dability index（ODI）, visual analogue scale（VAS） were assessed at pre-operation, post-operation and follow up. Clinical and radiographic parameters were compared between the two groups. Results The average follow up period was （51± 11） months（24-120 months）. The preoperative Cobb angles were 41.9°＋ 10.7°. Two groups of patients had similar preoperative and postoperative lumbar curve correction; there was no significant differences in SVA （sagittal vertical axis） between two groups. Preoperative L4.5 or L5S1 tilt existed in all two groups of patients. After surgery, there were significant differences in correction of L5S1 tilt （LIV=L5, 2.1° and 8.1°＋3.7°, LIV=S1, 3.8°＋2.4° and 8.1°＋2.9°, LIV=S2, 3.1°±2.8° and 8.7°±3.9°） in DLS patients with TLIF, and patients in TLIF group had better preservation of correction than those in no TLIF group at final follow-up. Coronal bal- ance distance （coronal balance distance, CBD） of TLIF group at final follow-up was significantly less than no TLIF group （1.8 ± 0.9 cm and 2.5 ± 1.5 cm）. Patients in TLIF group had a significantly higher fusion rate （100%, 11/11 and 93.75%, 15/16） and less postoperative complications than those from no TLIF group. Conclusion Performing TLIF at convex side could even the lumbar- sacral junction, promote the fusion process, and reduce the risk of postoperative coronal imbalance in preoperative coronal imbalance type C DLS patients.