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

English Keywords:Anterior cervical fixation and fusion  Delayed deep infection  Clinical characteristics  Imaging observation

English Abstract:

  【Abstract】 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 interval 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 258ml(80-500ml), and the average operation time was 166min(95-260min). 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.