颈椎前路内固定术后迟发性深部感染的临床特点和影像学观察

Clinical characteristics and imaging observation of delayed deep infection after anterior cervical fixation and fusion

目的 :探讨颈椎前路内固定术后发生迟发性深部感染患者的临床特点及其影像学变化特征。方法 :回顾分析2013年2月~2018年12月在我科行颈椎前路内固定手术的1896例患者资料,其中7例患者术后发生迟发性深部感染(首次感染发生时间>术后30d),院外转入1例。收集8例颈前路内固定术后迟发性深部感染患者的术前一般资料、术中情况;记录发生迟发性深部感染的间隔时间、体温、炎性指标、临床表现;分析迟发性深部感染患者的颈椎X线片、CT三位重建及MRI影像资料。结果:我院颈前路内固定术后迟发性深部感染的发生率为0.37%(7/1896),发生迟发性感染的平均间隔时间为术后16个月(3~39个月)。7例(87.5%)合并内科基础疾病,其中糖尿病4例,高血压病2例,糖尿病+高血压病1例,糖尿病在所有合并症中占71.4%。术中失血量平均258ml(80~500ml),手术平均时间166min(95~260min)。颈痛是迟发性感染患者最常见的临床症状,发生率为100%;其次为吞咽困难(50%,4/8)、切口窦道形成(25%,2/8)、神经损害(25%,2/8)以及发热(12.5%,1/8)。颈前路内固定术后迟发性感染患者炎性指标升高不明显,细菌学培养阳性率为12.5%(1/8)。颈椎MRI显示,8例(100%)患者存在椎体信号改变(T2加权高信号,T1加权低信号),7例(87.5%)患者伴椎前脓肿形成,4例(50.0%)感染累及手术节段椎间隙或邻近椎间隙。颈椎X线片及CT三维重建提示,5例(62.5%)患者出现融合节段椎间隙或邻近感染椎间隙塌陷,4例(50%)出现下颈椎后凸或邻近节段的局部后凸畸形,2例(25.0%)出现螺钉松动移位。结论:颈痛是颈椎前路内固定术后迟发性深部感染常见非特异性表现,常合并吞咽困难和(或)切口窦道形成及神经损害,较少存在发热和感染指标升高,且细菌学培养阳性率较低;结合颈椎MRI或CT可进一步诊断。

Objectives: To explore the clinical characteristics and imaging changes of patients with delayed deep infection after anterior cervical fixation and fusion. Methods: From February 2013 to December 2018,the data of 1896 patients who underwent anterior cervical fixation and fusion in our department were analyzed retrospectively. Among them, 7 patients developed delayed deep infection(the time of first infection >30 days after operation) and 1 patient was transferred into our hospital. The general data and intraoperative condition of 8 patients with delayed deep infection were collected. And the time interval, body temperature, inflammatory index and clinical characteristics were recorded. Analysis of X, CT three-dimensional reconstruction and MRI images of cervical spine in patients with delayed deep infection were analyzed. Results: The incidence of delayed deep infection after anterior cervical fixation and fusion was 0.37%(7/1896), and the average inter-val of delayed infection was 16 months(3-39 months). 7 cases(87.5%) were complicated with medical diseases,including 4 cases of diabetes, 2 cases of hypertension and 1 case of diabetes combined with hypertension.Diabetes accounted for 71.4% of all complications. The average intraoperative blood loss was 258 ml(80-500 ml), and the average operation time was 166 min(95-260 min). Neck pain was the most common clinical symptom in patients with delayed infection, the incidence was 100%, followed by dysphagia(50%, 4/8),incision sinus formation(25%, 2/8), nerve damage(25%, 2/8) and fever(12.5%, 1/8). But there was no significant increase of inflammatory index in patients with delayed infection after anterior cervical fixation and fusion, and the positive rate of bacteriological culture was 12.5%(1/8). MRI of cervical spine showed that 8 patients(100%) had signal changes of vertebral body(T2 weighted high signal, T1 weighted low signal), 7 patients(87.5%) were accompanied with prevertebral abscess formation, 4 cases(50.0%) had infection involving the intervertebral space or adjacent intervertebral space. Cervical X-ray and CT three-dimensional reconstruction showed that 5 patients(62.5%) had intervertebral space collapse of fusion segment or adjacent infected intervertebral space, 4 patients(50%) had lower cervical kyphosis or local kyphosis of adjacent segment, and 2 patients(25.0%) had screw loosening and displacement. Conclusions: Neck pain is a common but non-specific symptom for patients with delayed deep infection after anterior cervical fixation and fusion,and it is often combined with dysphagia and/or incision sinus formation and nerve damage. There is less fever and increased inflammatory index, and the positive rate of bacteriological culture is low for those patients.Combined with MRI or CT, delayed deep infection can be further diagnosed.