老年脊柱pQCT

老年脊柱椎体外周骨定量CT（pQCT）测定研究,目的 研究老年及各老龄段T3至L5椎体骨密度，椎体横断面面积。 方法 用外周骨定量CT（pQCT）仪测量40具老年尸体600个椎体的总骨密度，松质骨密度，皮质下骨密度，皮质骨密度，椎体横断面总面积，松质骨面积，皮质下骨面积及皮质骨面积。分别统计60岁-69岁(A组)、70岁-79岁(B组)、80岁-89岁(C组)、90岁-98岁(D组) 椎体骨密度值。,结果 T3至L5椎体总骨密度为188.25mg/cm3191.60mg/cm3，松质骨密度为128.01mg/cm3130.66mg/cm3，皮质下骨密度为454.90mg/cm3461.87mg/cm3，皮质骨密度为764.13mg/cm3769.55mg/cm3。60岁79岁椎体总骨密度值保持在相对稳定水平，80岁以后该值下降较明显。结论 为国内开展脊柱骨质疏松症研究及椎体pQCT测量提供参考数据，为进行欧洲人与国人脊柱椎体骨密度对比提供依据。,随着全世界人口老龄化，骨质疏松症已成为多发病及常见病。在德国，人口老龄化问题更为突出，对此病的研究投入较大。以往DXA（双能量X射线吸收技术)一直被当做诊断骨质疏松症及随访观察的标准测定方法，但DXA只能测量二维面积骨密度（mg/cm2），不能分别测定松质骨和皮质骨的密度，以致测量老年人腰椎时可能出现骨密度增加，其部分原因是腰椎骨质增生硬化所致。,pQCT（外周骨定量CT peripheral quantitative computed tomography)不仅能测量三维体积骨密度（mg/cm3)，而且能分别测量松质骨和皮质骨的体积骨密度。2000年4月-2001年1月，在德国慕尼黑大学医学院解剖研究所应用pQCT测量40具老年尸体T3L5骨密度。,材料与方法 40具德国人尸体，男16具，女24具，去世时年龄60岁-98岁，平均80.5岁，身高1.47米1.79米，平均1.62米。60岁69岁（A组）10具，70岁79岁（B组）9具，80岁89岁（C组）14具，90岁98岁（D组）7具。详细检查尸体的健康记录，生前无肿瘤、骨病、骨质疏松症疾病，无长期服用激素、钙剂等药物史。,截取尸体标本T3L5椎体节段，仔细去除其周围肌肉，不损伤韧带及椎骨，制成胸腰椎脊柱标本。摄正侧位X光片，根据California大学骨质疏松组脊柱X光诊断标准给每一椎体评级。将上述胸腰椎标本从T5T6、T8T9、T11T12、L2L3椎间盘处平行切断，制成每3个椎体一段标本（T3T5、T6T8、T9T11、T12L2、L3L5），再放入标本固定液内。,骨密度测定 将需测量标本从固定液中取出，放入装有自来水的桶中，在真空机内抽真空12小时以上，抽出标本内及水中的气体。在水中将标本用塑料袋包裹并封口，确保为真空状态。使用德国产XCT3000 pQCT测量仪，与椎体平行CT扫描，分别测定T3L5每一个椎体高度25%、50%、75%三幅断层骨密度，层厚2mm，将此三幅断层骨密度的均值作为该椎体骨密度值。,pQCT能分别测定每一椎体总骨密度(总BMD)，松质骨密度(松质骨BMD)，皮质下骨密度（皮质下骨BMD) ，皮质骨密度(皮质骨BMD)，椎体横断面总面积(TOT-A)，松质骨面积(TRAB-A)，皮质下骨面积(CRTSUB-A)，皮质骨面积(CRT-A)。,统计学分析 采用SAS软件对数据进行统计学分析，计算均值和标准差，并对A、B、C、D四组进行方差分析，当F检验有显著意义后，再作各组均数间的两两比较，即Q检验。,结 果 脊柱X光片评级 : 分03级。 0级：正常，椎体无骨折。1级：椎体轻度骨折，与同一椎体或相邻椎体比较，椎体前、中或/和后椎体高度减少20%25%。 2级：椎体中度骨折，椎体前、中或/和后椎体高度减少25%40%。 3级：椎体重度骨折，椎体前、中或/和后椎体高度减少40%。,表1 X光椎体评级结果（个） 0级1级2级3级 T3 40 T4 40 T5 40 T6 38 1 1 T740 T840 T940 T1040 T1138 2 T1234 6 L136 2 2 L237 3 L338 1 1 L437 2 1 L540,表1看出，脊柱负重主要集中在T11L4椎体，尤其是T12、L1椎体。6例T12椎体发生1级压缩骨折，占15%，4例L1椎体发生12级压缩骨折，占10%；L2、L4发生压缩骨折各7.5%；T6、T11、L3发生压缩骨折各5%。其它椎体高度均正常。,表2 T3L5椎体骨密度pQCT测量结果 (mg/cm3)椎体 总BMD 松质骨BMD皮质下骨BMD皮质骨BMDT3 191.4025.91130.6610.88456.8324.97764.3735.04T4 189.0124.20129.8213.36454.9027.50764.1335.28T5 188.5422.75128.6810.63458.1624.70765.7432.23T6 188.4326.81128.1314.07457.3825.98767.0331.90T7 189.0126.18128.0110.47460.2222.65768.6230.26T8 188.25 26.64128.1713.86457.4227.83766.2433.82T9 190.7327.53128.7711.16460.9625.42768.5430.94T10 189.7328.17129.0115.39458.5128.97767.9336.63T11 190.3528.98128.6512.63460.1824.33768.6533.35T12 189.2328.62128.8015.15458.0926.06766.8833.67L1 190.3028.13128.7211.29460.1420.72767.1028.59L2 189.6629.63128.8415.53458.5227.51767.8833.19L3 191.6027.96129.0911.52461.8721.41769.5527.44L4 189.8128.32128.7915.35459.3124.01767.2430.99L5 191.2628.57128.5611.70460.6921.12767.9028.22,表3 T3L5椎体面积pQCT测量结果 (mm2 )椎体 TOT_A TRAB_A CRTSUB_A CRT_AT3 885.98293.28725.93250.76160.0569.7133.8420.63T4 897.65314.90736.47260.64161.1775.1533.3722.22T5 929.77291.17764.03243.57165.7472.0435.6321.53T6 946.67310.80773.75249.56172.9289.1037.2027.55T7 971.80266.46795.27219.68176.5283.4139.0125.91T8 947.47308.83775.41248.30172.0689.0537.0527.91T9 963.21274.78786.62230.31176.5981.9139.0725.81T10 943.56323.11770.80263.86172.7689.6137.0227.71T11 972.13289.09794.53246.16177.6084.7739.0526.30T12 944.01332.39772.12272.91171.9091.4736.7727.86L1 960.03387.31784.94242.60175.0985.5638.4626.42L2 933.07320.19763.09264.32169.9991.3036.7728.22L3 949.16280.09774.54240.23174.6279.8238.6324.44L4 936.39322.20765.10266.19171.3088.5536.7727.09L5 976.65298.19794.80246.89181.8694.0839.9529.00,从表2,3看出，T3L5椎体总骨密度、松质骨密度、皮质下骨密度、皮质骨密度值相差不大。但总面积、松质骨面积、皮质下骨面积、皮质骨面积从T3至L5逐渐增大。,各年龄段椎体骨密度 pQCT测量及对比分析,表4 AD各组T3L5椎体总骨密度pQCT测定结果 (mg/cm3) 椎体 A 组 B 组 C 组 D 组T3196.9833.47191.0620.47*184.1026.54185.8810.06T4197.0822.86192.7229.86*183.1525.59183.9713.86T5195.2023.24193.4636.50*184.0919.80182.9014.93 T6195.6324.71190.5018.88*184.4429.88182.8123.73 T7194.5911.39191.5629.39*185.4328.56184.5925.99T8194.9529.17192.5734.45*184.7124.60183.3318.05T9195.6330.16191.0532.81*184.5224.46184.3429.98T10196.7622.55192.3130.38*184.7627.31181.2127.67T11202.0929.52192.9531.82*185.4218.78181.2021.60T12202.8031.66193.7831.97*184.0427.80182.7521.05L1201.1933.75191.2931.03*184.6626.60183.3116.58L2200.0635.29191.0931.59*184.2426.57183.0520.35L3201.6932.48192.2815.57*185.5730.62184.8812.91L4201.2624.60192.2621.82*184.8625.82182.0423.98L5202.9028.08193.0913.16*185.1428.87183.6517.36 注：与A组同一椎体比较， P0.05,表5 AD各组T3L5椎体松质骨密度pQCT测定结果 (mg/cm3)椎体 A 组 B 组 C 组 D 组T3 133.509.57128.4711.20129.6212.69129.337.57T4 133.139.94132.2411.43126.7816.11126.3913.17T5 133.108.50131.3811.21126.7512.29126.419.50T6 131.9111.01130.4910.09126.3416.36126.6713.66T7 131.638.52130.3811.36126.7211.82126.769.38T8 130.5410.85130.2911.31127.4616.06126.8710.90T9 130.048.26130.1210.00126.0012.70128.6013.47T10 132.118.94130.449.56128.1814.10125.9512.45T11 132.749.34131.3512.80127.4512.52125.5614.23T12 132.3011.07129.9513.75127.6514.66126.4113.47L1 131.5211.03128.3512.36127.5912.21127.6910.73L2 130.0710.80127.8912.74128.2213.40127.5814.05L3 132.609.05128.4310.94129.9312.33126.5013.20L4 133.199.80126.7614.43128.6612.94125.9314.78L5 133.667.49126.728.70128.5110.58125.1612.51 注： 各组方差分析均无显著性差异，P0.05,表6 AD各组T3L5椎体皮质下骨密度pQCT测定结果 (mg/cm3)椎体 A 组 B 组 C 组 D 组T3 452.0631.31448.0328.13455.7323.97464.5120.89T4 452.2630.54447.5336.57452.0525.54463.5918.16T5 450.2613.71449.7035.04456.8427.53466.8215.37T6 451.2820.14451.3832.59455.7627.47464.6221.57T7 452.6919.79448.3124.66463.6725.60465.4724.24T8 453.5627.99447.7334.90459.4926.77463.2526.18T9 457.7923.72451.9135.12457.9021.66468.1520.83T10 462.1732.24451.7734.93455.0025.28466.6521.86T11 462.8921.17457.5834.06453.1824.26467.5827.70T12 464.5832.90454.6333.91455.3624.39458.1316.79L1 462.1724.75454.6517.77462.8723.47458.8314.44L2 460.7632.92453.7317.84462.0224.38461.0322.80L3 458.7525.11456.4017.46465.1920.10463.9722.31L4 463.0130.97454.7918.95461.1425.09459.0817.97L5 465.4423.28453.1622.54463.0123.21456.4814.93 注： 各组方差分析均无显著性差异，P0.05,表7 AD各组T3L5椎体皮质骨密度pQCT测定结果 (mg/cm3)椎体 A 组 B 组 C 组 D 组T3 748.5031.39754.1338.26764.3731.89780.6633.31T4 747.8932.83750.8034.16763.3931.24786.8725.48T5 748.1317.31754.4241.12768.4536.72782.1416.18T6 749.6628.67763.2343.21768.8929.78783.9217.59T7 748.7823.48750.0329.19777.1829.67781.8524.36T8 752.1526.16751.7831.64774.6735.52782.2430.55T9 760.4025.98752.4239.56773.1730.46781.9223.59T10 762.9231.70758.4043.43761.4035.58783.4734.43T11 761.6825.97758.4636.40764.9932.87782.8237.56T12 761.2230.98761.8043.06766.8628.96775.8022.52L1 753.3227.24754.0532.13772.4929.94772.7928.03L2 755.3035.61757.9440.15774.6225.95780.9629.70L3 754.1125.91756.2430.10778.2525.28780.4024.34L4 757.3834.97760.9928.18770.2932.14776.5629.32L5 759.4926.69752.9130.54771.7928.21779.9233.65 注： 各组方差分析均无显著性差异，P0.05,从表4看出，T3至L5椎体总骨密度C、D组均低于A组，有显著性差异 (P0.05)；C、D组也低于B组，但无显著性差异。从表57看出，椎体松质骨密度、皮质下骨密度、皮质骨密度 A、B、C、D各组间均无显著性差异。,讨 论,pQCT具有放射剂量低，检查费用低，精确度高的优点。人体脊柱QCT检查精确度为2%4%，准确度为5%15%，而pQCT检查精确度更高，为0.2%1.0%，准确度为7%20%。DXA由于采用的是二维空间测量方法，测出的结果是面积骨密度mg/cm2，骨骼厚度无法测定，因此这一指标对结果的解释会引发一些错误的概念。而pQCT测量的是三维空间的体积骨密度，通常被认为代表的是真正的体积骨密度。此外，pQCT能分别测量松质骨、皮质骨骨密度等。,本研究40具尸体，健康记录中均无骨质疏松症的诊断及长期服用激素、钙剂史。pQCT测量共600个椎体，其中22个椎体有压缩骨折，占3.67%。40具标本中T3,4,5,7,8,9,10及L5均无骨折，发生椎体压缩骨折的最多部位是T12，占15%，但均为轻度压缩骨折，2个重度椎体压缩骨折分别在T6及L4椎体。,pQCT测量40具标本T3L5椎体,总骨密度为188.25mg/cm3191.60mg/cm3, 松质骨密度为128.01 mg/c