经椎间孔腰椎椎间融合术后对侧神经根性症状的原因分析

Contralateral radiculopathy after unilateral transforaminal lumbar interbody fusion

目的探讨经椎间孔腰椎椎间融合（Transforaminal lumbar interbody fusion，TLIF）术后对侧神经根性症状的发生率及危险因素。方法回顾性分析2010年1月至2014年1月接受单侧TLIF的腰椎退行性疾病患者587例，男334例，女253例；年龄19-71岁，平均57．1岁。根据术后是否出现对侧神经根症状将患者分为有症状组和无症状组，通过两组影像学资料分析出现症状的可能原因。比较两组手术前后对侧椎间孔面积、节段前凸角及其差值。采用疼痛视觉模拟评分（visual analogue scale，VAS）和13本整形外科学会（Japanese Oahopaedic Association，JOA）腰椎评分评估疗效。结果术后随访9-21个月，平均15．1个月。TLIF术后出现对侧神经根性症状28例，发生率4．8％（28／587）。单节段27例，双节段1例。术前诊断为腰椎管狭窄13例，退变性腰椎滑脱伴椎管狭窄7例，腰椎峡部裂伴滑脱6例，复发性椎间盘突出2例。原因为对侧椎间孔狭窄16例（57．1％，16／28），螺钉位置不良5例（17．9％，5／28），对侧侧隐窝狭窄和（或）椎间盘突出加重3例（10．7％，3／28），术后血肿1例（3．6％，1／28），骨水泥压迫1例（3．6％，1／28），不明原因2例（7．1％，2／28）。19例在保守治疗无效后接受翻修术，翻修率3．2％（19／587）。有症状组手术前后对侧椎间孔面积差值为（-13．8±13．2）mm^2，节段前凸角差值为7．0°±9．8°，与无症状组比较差异有统计学意义。两组术后3个月疼痛VAS评分的差异无统计学意义；JOA腰椎评分改善率无症状组为63．0％±18．1％，有症状组为46．7％±20．1％，差异有统计学意义（t=-3．784，P〈0．05）。结论腰椎TLIF术后出现对侧神经根性症状的发生率为4．8％，可能的危险因素主要包括对侧椎间孔狭窄和螺钉位置不良。提示应严格掌握单侧TLIF手术适应证，避免在未有效增加椎间隙高度的基础上行腰椎前凸恢复，是减少对侧神经压迫及术后出现神经根性症状的关键。

Objective To analyze the incidence and risk factors of contralateral radiculopathy in patients after unilateral transforaminal lumbar interbody fusion （TLIF） surgery. Methods A retrospective study was conducted within 587 patients （average age 57.1 years, range 19-71 years） who underwent unilateral TILF from January 2010 to January 2014 in our hospital, including 334 males and 253 females. Patients were divided into a symptomatic group and an asymptomatic group. The causes of contralateral neurological symptom were evaluated according to the radiological data. The difference of pre- and post-operative contralateral foramen area （CFA）, segmental angle （SA） and the clinical treatment outcomes （VAS, JOA score） were compared between two groups. Results Patients were followed up for 9-21 months, average 15.1 months. Post-operative contralateral radiculopathy occurred in 28 （4.8%） of the patients who underwent unilateral TLIF, including contralateral foraminal stenosis in 16 （57.1%, 16/28）, screw malposition in 5 （17.9%, 5/28）, contralateral lateral recess stenosis and/or newly developed disc herniation in 3 （10.7%, 3/28）, hematoma in 1 （3.6%, 1/28）, cement compression in 1 （3.6%, 1/28）, and unknown origin in 2 patients （7.1%, 2/28）. Nineteen （3.2%, 19/587） of the 28 patients received revision surgery because of ineffective conservative treatment. Compared with the asymptomatic group, the difference of pre-and post-operative CFA was significantly smaller （-13.8±13.2 mm^2） in symptomatic group, while the SA was significantly greater （7.0°±9.8°） in symptomatic group. The JOA score at 3 months after the surgery was significantly improved in asymptomatic group （63.0%±18.1%, P〈0.05）. Conclusion The incidence rate of contralateral neurological symptom was 4.8% in the present study. The potential risk factors associated with contralateral radiculopathy were predominantly contralateral foraminal stenosis and screw malposition. The excessive restoration of SA might have an effect on contralateral nerve compression, which should arouse the attention of the surgeon.