女性腰椎退行性病变患者腰椎CT值对骨质疏松症的诊断作用

Effect of lumbar CT values in the diagnosis of osteoporosis in women patients with lumbar degenerative diseases

背景:双能X射线吸收法可能会错误地抬高严重腰椎退行性病变患者的骨密度值,而腰椎松质骨CT值可能协助双能X射线吸收法减少骨质疏松症的漏诊。目的:应用腰椎CT值来诊断女性腰椎退行性病变患者中的骨质疏松症。方法:回顾性分析在新疆医科大学第六附属医院脊柱外科住院诊疗的192例女性患者骨密度检测结果和腰椎CT等临床资料。根据CT上腰椎退变严重程度,将患者分为退变组(n=107)和对照组(n=85)。测量两组患者L1椎体中轴松质骨CT值,记录L_(2)-L_(4)及髋部T值和骨密度均值。参考先前的研究,L1椎体CT值≤110 HU诊断为骨质疏松,比较两组患者通过双能X射线吸收法和CT值诊断骨质疏松的患病率。结果与结论:(1)两组患者CT值与L_(2)-L_(4)椎体的T值、骨密度均值均呈显著正相关(P<0.001),而对照组中相关性更高;(2)退变组中腰椎T值和骨密度均值显著高于对照组(P<0.05),CT值明显低于对照组(P=0.001),而两组的髋部T值和骨密度均值相比差异无显著性意义;(3)所有患者经CT阈值诊断的骨质疏松症患病率高于T值诊断的骨质疏松(51.0%和42.7%);(4)两组在110例经双能X射线吸收法确诊为非骨质疏松的患者中,CT值诊断的骨质疏松症患病率高达23.6%,而退变组中的患病率比对照组更高(分别为31.7%和14.0%);(5)漏诊的骨质疏松症患病率在退变组中经腰椎双能X射线吸收法确诊的非骨质疏松患者中高达38.6%(27/70),而对照组中为19.6%(11/56);(6)提示骨质疏松症在年龄≥50岁的女性腰椎退行性病变患者中很常见;测量腰椎松质骨CT值可作为此类患者诊断骨质疏松症的有效补充方法,尤其是在严重退变的腰椎退行性病变患者中能够发现更多漏诊的骨质疏松症患者。

BACKGROUND:Patients with severe lumbar degenerative disease may have their bone mineral density incorrectly raised by dual-energy X-ray absorptiometry.While lumbar cancellous bone Hounsfield unit value can assist dual-energy X-ray absorptiometry in reducing osteoporosis misdiagnosis.OBJECTIVE:To identify osteoporosis in woman patients with lumbar degenerative diseases using lumbar CT scans.METHODS:Bone mineral density test results and lumbar CT data of 192 women patients who were treated at the Department of Spine Surgery,Sixth Affiliated Hospital of Xinjiang Medical University were retrospectively reviewed.All patients were divided into a degeneration group(n=107)and a control group(n=85)according to the criteria of severity of vertebral degeneration as assessed on CT of the lumbar spine.The CT value of axial cancellous bone of L1 vertebral body was measured in the two groups.The T score and bone mineral density of the hip and L_(2)-L_(4) were recorded.According to previously published studies,osteoporosis was diagnosed at L1 vertebral CT values≤110.The prevalence of osteoporosis diagnosed by dual-energy X-ray absorptiometry and CT values was compared between the two groups.RESULTS AND CONCLUSION:(1)CT values were significantly and positively correlated with T scores and mean bone mineral density of the L_(2)-L_(4) vertebrae in both groups(P<0.001),while the correlation was higher in the control group.(2)Lumbar T scores and bone mineral density values were significantly higher in the degeneration group than those in the control group(P<0.05)and CT values were significantly lower in the degeneration group than that in the control group(P=0.001).Hip T scores and bone mineral density were not significantly different in the two groups.(3)The prevalence of osteoporosis diagnosed by CT thresholds was higher in all patients than that diagnosed by T values(51.0%and 42.7%).(4)The prevalence of osteoporosis diagnosed by CT values was as high as 23.6%in the 110 patients diagnosed with non-osteoporosis by dual energy X-ray absorptiometry in both groups,and was higher in the degeneration group than that in the control group(31.7%and 14.0%,respectively).(5)The prevalence of missed osteoporosis was as high as 38.6%(27/70)of non-osteoporosis patients diagnosed by dual-energy X-ray absorptiometry of the lumbar spine in the degeneration group compared to 19.6%(11/56)in the control group.(6)It is concluded that osteoporosis is common in female patients with lumbar degenerative diseases aged≥50 years.Measurement of lumbar cancellous bone CT values may be a useful complementary method for diagnosing osteoporosis in patients with lumbar degenerative diseases,especially in patients with severe degenerative lumbar degenerative diseases where more missed osteoporosis patients can be identified.