腰肌指数、腰椎椎体骨髓脂肪分数与骨密度关系及对骨质疏松的诊断效能

目的探讨腰肌指数(psoas muscle index,PMI)、腰椎椎体骨髓脂肪分数(fat fraction,FF)与骨密度(bone mineral density,BMD)间的关系及对骨质疏松(osteoporosis,OP)的诊断效能。方法选取四川省骨科医院2018年3月至2021年5月BMD筛查的200例检查者作为研究对象,根据BMD分为骨量正常组(T值≥-1.0,n=105)、骨量减少组(-2.5<T值<-1.0,n=57)、OP组(T值≤-2.5,n=38)。对比三组一般资料及BMD、PMI、腰椎椎体骨髓FF,分析PMI、腰椎椎体骨髓FF与BMD间关系,建立OP的Logistic回归模型,评估PMI、腰椎椎体骨髓FF对OP的诊断效能。结果OP组BMD、PMI低于骨量减少组、骨量正常组,FF高于骨量减少组、骨量正常组(P<0.05);骨量减少组的BMD、PMI低于骨量正常组,FF高于骨量正常组(P<0.05);PMI与BMD呈正相关,腰椎椎体骨髓FF与BMD呈负相关(P<0.05);年龄、身体质量指数(body mass index,BMI)、PMI、腰椎椎体骨髓FF是骨量减少的影响因素,年龄、PMI、腰椎椎体骨髓FF是OP的影响因素(P<0.05);腰椎椎体骨髓FF联合诊断OP的受试者工作特征(receiver operating characteristic,ROC)曲线下的面积(area under curve,AUC)为0.853,大于单一指标诊断值(P<0.05)。结论PMI、腰椎椎体骨髓FF是BMD的独立影响因素,二者联合在OP诊断中具有较高效能。

应用骨髓脂肪指数评价狍冬季体状况

Fat content of bone marrow has long been related to physiological condition in deer. To assess body condition of roe deer (Capreolus capreolus), marrow fat index was employed. Tibiae, radii, metacarpal and metatarsal bones of 6 roe deer were collected in Xiaodong Forestry Region during winter season in 1999, the marrow fat contents were analyzed by use of ether extraction, oven-drying, and reagent-drying method respectively, and the ages were determined by dental cementum. The results of comparison of marrow fat content for each bone after ether extraction, oven-drying, and reagent-drying indicated a high degree of similarity (P>0.05). No significant differences existed between the tibia and radius, metacarpal and metatarsal bone (P>0.05). Low level of bone marrow fat content (54.93±30.88%, measured by ether extraction method for tibia) meant that roe deer remained in a phase of undernutrition. Under low crude protein and energy content of natural vegetation and low digestibility of browse during winter, roe deer relied primarily on diet and its fat stores to partially meet energy requirements. As roe deer’s nutritional status declined, its body fat stores were mobilized and depleted, which can be reflected by the low kidney fat content (12.50±8.34%). Marrow fat index along with kidney fat index can be useful as a indicator in assessing roe deer’s body condition.

股骨颈强度指数及骨髓脂质在评价骨质疏松性髋部骨折中的作用

目的探讨股骨颈强度指数(FSI)及骨髓脂质分数(LF)在预测股骨颈脆性骨折风险中的价值。方法女性股骨颈骨折患者17例及正常对照组68例行DXA扫描获取股骨颈骨密度(FN_BMD)及FSI,MRS扫描获取LF。Bayes法建立股骨颈骨折判别方程,比较FSI及LF骨折风险判别效果。结果 LF与FN_BMD(r=-0.581)、FSI(r=-0.408)呈中度负相关(P均<0.05)。校正年龄、身高、体重、BMI,LF与FN_BMD、FSI相关性依然存在。校正上述混杂因素,骨折组FSI(1.10±0.16)较正常对照组(1.37±0.25)低,LF(79.2±16.4%)较对照组(57.9±16.8%)高(P均<0.05)。校正FN_BMD,FSI、LF在组间仍存在统计学差异。包含LF判别方程对骨折判别的敏感性、特异性分别为74.7%、68.4%,准确率为68.2%(自身回代法)、65.9%(交互校验法);包含FSI判别方程对骨折判别的敏感性、特异性分别为79.7%、76.9%,准确率为76.5%、72.9%。结论LF及FSI独立于BMD决定髋部骨强度的有用因子,MRS测定LF对预测髋部脆性骨折有一定价值。

绝经后新诊断2型糖尿病腰椎骨髓脂肪成分的MRS测定

目的探讨磁共振波谱成像(MRS)用于定量绝经后新诊断2型糖尿病(T2DM)病人骨髓脂肪成分的变化,并分析其与糖化血红蛋白(HbA1C)的相关性。方法收集25例绝经后新诊断T2DM女性病人,年龄(57.4±4.5)岁,以25例健康女性作为对照者,年龄(56.6±4.0)岁。两组均行腰3椎体1H-MRS扫描,计算骨髓脂肪含量(FC)及不饱和脂肪指数(UFI)。测定被检者空腹血糖及HbA1C。采用独立样本t检验比较组间年龄、体质量指数(BMI)、血糖、HbA1C、FC及UFI差异,采用Pearson相关分析两组的FC、UFI与血糖及HbA1C的相关性。结果T2DM组骨髓FC值(63.2%±7.4%)与正常对照组(60.9%±6.9%)差异无统计学意义,但T2DM组骨髓UFI(6.1%±0.8%)较正常对照组(7.6%±0.9%)降低(t=-3.775,P<0.001)。T2DM组HbA1C>7.0%者的骨髓FC(66.0%±6.3%)高于HbA1C≤7.0%者(57.6%±6.5%)(t=2.893,P<0.001)。T2DM组骨髓FC与HbA1C呈高度正相关(r=0.801,P<0.001),而骨髓UFI与HbA1C水平呈负相关(r=-0.746,P<0.001),但FC(r=0.226,P=0.206)和UFI(r=-0.184,P=0.589)与血糖无相关性。结论 T2DM病人腰椎骨髓FC可无明显变化,但UFI明显降低。T2DM骨髓脂肪成分与HbA1C密切相关,MRS测定骨髓脂肪组分可看作血糖控制程度的标志。