重度陈旧性胸椎结核后凸患者影像学参数与迟发性神经功能损伤的相关性

Correlation between imaging parameters and delayed neurological impairment in patients with severe post-tuberculous thoracic kyphosis

目的探讨重度陈旧性胸椎结核后凸患者的影像学参数与神经功能的相关性,筛选出与迟发性神经功能损伤相关的影像学指标。方法回顾性分析2013年1月—2018年7月收治的56例重度陈旧性胸椎结核后凸畸形患者的一般临床资料和影像学资料。根据患者入院时是否出现下肢神经功能症状分为症状组(41例)和无症状组(15例)。术前在全脊柱正侧位X线片上测量胸椎后凸Cobb角,在术前胸椎MRI上测量顶椎区脊髓夹角(SA)、脊髓矢状径比(SDR)、脊髓横截面积比(SAR)。采用二元logistic回归分析影像学参数是否为出现神经功能症状的主要相关因素。所有患者均在重力牵引后采用胸椎后凸截骨术治疗,采用Frankel分级评估神经功能。结果症状组顶椎区脊髓SDR和顶椎区SA均低于无症状组(0.476±0.081 vs.0.772±0.097,78.0°±12.4°vs.97.3°±15.5°),差异有统计学意义(P<0.05);2组间胸椎后凸Cobb角和顶椎区脊髓SAR差异无统计学意义(P>0.05)。症状组顶椎区脊髓SDR≥0.476者术后Frankel分级改善情况优于顶椎区脊髓SDR<0.476者,差异有统计学意义(P<0.05)。二元logistic回归分析结果显示,顶椎区脊髓SDR<0.476是出现神经功能症状的独立相关因素(比值比=15.666,95%置信区间为7.426~33.048,P<0.05)。结论重度陈旧性胸椎结核后凸会出现迟发性神经损伤,顶椎区脊髓SDR与神经功能症状的出现密切相关,当患者脊髓SDR<0.476时建议手术治疗。

Objective To investigate the correlation between imaging parameters and neurological function in patients with severe post-tuberculous thoracic kyphosis,and to screen out the imaging indicators related to delayed neurological impairment.Methods The general clinical data and imaging data of 56 patients with severe post-tuberculous thoracic kyphosis who were admitted from January 2013 to July 2018 were retrospectively analyzed.The patients were divided into symptomatic group(41 cases)and asymptomatic group(15 cases)according to the lower extremity neurological function at admission.The thoracic kyphosis Cobb angle was measured on preoperative whole spine roentgenography.Preoperative thoracic MRI was used to measure the spinal angle(SA),the spinal cord sagittal diameter ratio(SDR),and the spinal cord sectional area ratio(SAR)in the apical vertebrae.Binary logistic regression analysis was used to analyze the correlation between the measurement value and the neurological impairment.All the patients were treated with thoracic kyphosis osteotomy after gravity traction,and neurological function was assessed by Frankel grading.Results The spinal cord SDR and SA of the apical vertebrae in the symptomatic group were significantly lower than those in the asymptomatic group(0.476±0.081 vs.0.772±0.097,78.0°±12.4°vs.97.3°±15.5°,P<0.05).There were no significant differences between the 2 groups in terms of thoracic kyphosis Cobb angle or spinal cord SAR in the apical vertebrae(P>0.05).In the symptomatic group,the improvement of Frankel grading in patients with spinal cord SDR in the apical vertebrae≥0.476 was better than that in patients with spinal cord SDR in the apical vertebrae<0.476(P<0.05).Binary logistic regression analysis showed that spinal cord SDR in the apical vertebrae less than 0.476 was an independent risk factor for neurological impairment(odds ratio=15.666,95%confidence interval 7.426-33.048,P<0.05).Conclusions Severe post-tuberculous thoracic kyphosis may cause delayed nerve injury,and the spinal cord SDR in the apical region is closely related to delayed neurological impairment.When the spinal cord SDR in the apical vertebrae is less than 0.476,surgical treatment is recommended.