腰椎椎体骨强度综合指数预测骨质疏松性椎体的压缩骨折

Prediction of osteoporotic vertebral compression fracture based on comprehensive index of lumbar vertebral bone strength

背景:骨质疏松性椎体压缩骨折是继发于骨质疏松症的常见骨折,目前尚缺乏有效的骨质疏松性椎体压缩骨折预测指标及方法。目的:探讨腰椎椎体骨强度综合指数对骨质疏松性椎体压缩骨折的预测作用。方法:纳入骨质疏松患者233例,根据是否发生椎体骨折分为骨折组和非骨折组。收集患者人口统计学、体质量指数、椎体骨密度等详细信息,拍摄腰椎X射线侧位片,测量并计算椎体宽度、椎体长度、骶骨倾斜角、骨盆倾斜角、骨盆入射角、腰椎抗压强度指数及腰椎抗冲击强度指数,对以上参数进行单因素及多因素分析,并进行受试者操作特征曲线(ROC)分析,根据截断值进行生存分析。结果与结论:①所有患者皆获得随访,随访时间2-4年,平均3.1年。随访期间,99例(L1椎体38例,L2椎体61例)患者发生骨折(骨折组),134例(L1椎体52例,L2椎体82例)患者未发生骨折(非骨折组);单因素分析显示两组年龄、性别、身高、体质量、体质量指数、骨折节段比较均无统计学意义(P>0.05)。②骨折组腰椎抗压强度指数、腰椎抗冲击强度指数均低于非骨折组(P<0.05)。骨折组骨盆入射角、骨盆倾斜角大于非骨折组(P<0.05)。③多因素分析显示,腰椎抗压强度指数、腰椎抗冲击强度指数及骨盆倾斜角是患者发生骨质疏松性椎体压缩骨折的危险因素(P<0.05)。④ROC曲线分析显示椎体骨密度、腰椎抗压强度指数、腰椎抗冲击强度指数、骨盆倾斜角和骨盆入射角的截断值分别为0.9135 g/cm2,1.932,0.903,21.5°,55°;曲线下面积(AUC)分别为0.630,0.800,0.911,0.633,0.568。⑤根据生存分析(以骨质疏松性椎体压缩骨折为终点),腰椎抗冲击强度指数≥0.903椎体平均生存时间显著大于腰椎抗冲击强度指数<0.903者(P<0.05)。⑥结果说明,腰椎椎体骨强度综合指数比椎体骨密度和脊柱-骨盆矢状位参数对骨质疏松性椎体压缩骨折预测更加精准,有助于早期防治骨质疏松性椎体压缩骨折。

BACKGROUND:Osteoporotic vertebral compression fracture is a common fracture secondary to osteoporosis.At present,there is no effective prediction index and method for osteoporotic vertebral compression fracture.OBJECTIVE:To investigate the predictive effect of the comprehensive index of lumbar vertebral body bone strength on osteoporotic vertebral compression fracture.METHODS:233 patients with osteoporosis were divided into a fracture group and a non-fracture group according to whether a vertebral fracture occurred.The demography,body mass index,vertebral bone mineral density and other details were collected.Lateral X-ray films of the lumbar spine were photographed.The vertebral body width,vertebral body length,sacral slope,pelvic tilt,pelvic incidence,lumbar compressive strength index and the lumbar impact strength index were measured,calculated,and analyzed by univariate and multivariate,and the receiver operating characteristic curve was analyzed.The survival analysis was conducted according to the cut-off value.RESULTS AND CONCLUSION:(1)All patients were followed up for 2-4 years,with an average of 3.1 years.During the follow-up period,99 cases(38 cases of L1 vertebral body,61 cases of L2 vertebral body)had fractures(fracture group),and 134 cases(52 cases of L1 vertebral body,82 cases of L2 vertebral body)had no fractures(non-fracture group).Univariate analysis showed that there was no significant difference in age,sex,height,body mass,body mass index and fracture segment between the two groups(P>0.05).(2)Lumbar compressive strength index and lumbar impact strength index in the fracture group were lower than those in the non-fracture group(P<0.05).Pelvic incidence and pelvic tilt in the fracture group were higher than those in the non-fracture group(P<0.05).(3)Multivariate analysis showed that lumbar compressive strength index,lumbar impact strength index and pelvic tilt were risk factors for osteoporotic vertebral compression fractures(P<0.05).(4)Receiver operating characteristic curve analysis showed that the cutoff values of vertebral bone mineral density,lumbar compressive strength index,lumbar impact strength index,pelvic tilt and pelvic incidence were 0.9135 g/cm2,1.932,0.903,21.5°and 55°,respectively;areas under the curve were 0.630,0.800,0.911,0.633 and 0.568,respectively.(5)According to the survival analysis(with osteoporotic vertebral compression fracture as the end point),the average survival time of the patients with lumbar impact strength index≥0.903 was significantly longer than that of the patients with lumbar impact strength index<0.903(P<0.05).(6)These findings conclude that the comprehensive index of lumbar vertebral body bone strength is more accurate than the bone mineral density of the vertebral body and spine-pelvis sagittal parameters in predicting osteoporotic vertebral compression fractures,which is helpful for early prevention and treatment of osteoporotic vertebral compression fractures.