基于影像学特征对骨质疏松性椎体压缩骨折病人经皮椎体成形术后同椎体再发骨折的预测研究

Predicting refracture of the cemented vertebrae after percutaneous vertebroplasty based on imaging features in patients with osteoporotic vertebral compression fracture

目的探讨基于影像学特征对骨质疏松性椎体压缩骨折(OVCF)病人经皮椎体成形术(PVP)后的列线图模型预测术椎椎体再发骨折的价值。方法回顾性纳入急性OVCF并行PVP后的病人93例。所有病人均行X线及MRI检查,根据椎体再发骨折诊断标准将病人分为再发骨折组(48例)和无再发骨折组(45例)。采用t检验和卡方检验比较2组间临床资料及影像特征的差异,对差异有统计学意义的指标进行多因素Logistic回归分析,获取再发骨折的独立危险因素,采用R软件建立列线图模型并绘制其校准曲线。采用受试者操作特征(ROC)曲线评估模型的预测效能,计算ROC曲线下面积(AUC)。应用校准曲线对列线图模型进行验证。结果再发骨折组的椎体高度恢复率、延伸至终板的骨折线、椎体内裂隙(IVC)、骨水泥周围积液及骨水泥-终板未接触(NPEC)与无再发骨折组的差异均有统计学意义(均P<0.05);多因素Logistic回归分析显示延伸至终板的骨折线[优势比(OR)=3.232]、存在IVC(OR=27.117)和NPEC(OR=1.993)及较高的椎体高度恢复率(OR=2.943)为同椎体再发骨折的独立危险因素(均P<0.05)。存在延伸至终板的骨折线的椎体骨质前份前移距离[(3.12±2.62)mm]大于无延伸者[(1.67±2.18)mm](P<0.05)。与不存在IVC病人相比,存在IVC病人的椎体高度恢复率(分别为7.19%±8.60%和12.63%±11.81%)和NPEC发生率[78.38%(58/74)和94.74%(18/19)]均更高(P<0.05)。列线图模型预测再发骨折的AUC为0.860,敏感度0.792,特异度0.844。校准曲线显示列线图预测概率与实际概率一致性尚可。结论基于影像学特征建立的列线图模型能够预测术椎椎体再发骨折。

Objective To explore the value of nomogram based on imaging features in predicting refracture of the cemented vertebrae after percutaneous vertebroplasty(PVP)in patients with osteoporotic vertebral compression fracture(OVCF).Methods Ninety-three patients with acute OVCF who had undergone PVP were retrospectively included.All patients underwent X-ray and MRI examinations.According to the diagnostic criteria for recurrent vertebral fractures,the patients were divided into a refracture group(48 cases)and a non-refracture group(45 cases).The t test and chi-square test were used to compare the differences in clinical data and imaging characteristics between the two groups,and multivariate Logistic regression analysis was performed on the indicators with statistical significance to obtain independent risk factors for refractures.R software was used to establish a nomogram model,and calibration curve of the model were drawn.Receiver operating characteristic(ROC)curve was used to evaluate the predictive power of the model,and the area under the ROC curve(AUC)was calculated.The calibration curve was applied to validate the nomogram model.Results The vertebral height recovery rate,fracture line extending to the endplate,intravertebral fissure(IVC),fluid accumulation around bone cement and non-PMMA-endplate-contact(NPEC)in the recurrent fracture group were significantly different from those in the non-recurrent fracture group(all P<0.05).Multivariate Logistic regression analysis showed endplate cortical disruption(OR=3.232),IVC(OR=27.117),NPEC(OR=1.993),vertebral height recovery rate(OR=2.943)were independent risk factors for refracture(all P<0.05).The anterior displacement of the vertebral body bone with the fracture line extending to the endplate(3.12±2.62 mm)was greater than that in the absence of the fracture line extending to the endplate(1.67±2.18 mm)(P<0.05).Compared with the patients without IVC,the recovery rate of vertebral body height in the patients with IVC(7.19%±8.60%and 12.63%±11.81%,respectively)and the incidence of NPEC[78.38%(58/74)and 94.74%(18/19)]were significantly higher(P<0.05).The AUC of the nomogram model for predicting recurrent fracture was 0.860,the sensitivity was 0.792,and the specificity was 0.844.The calibration curve showed that the predicted probability of the nomogram was in good agreement with the actual probability.Conclusion The nomogram established based on imaging features can predict the refracture of the cemented vertebrae.