椎体変形と腰椎海綿骨骨塩量の関連-360症例の検討

QCTによる腰椎海綿骨骨塩量と,圧迫骨折を含む,椎体(第11胸椎～第4腰椎)の変形率の関係を検討した｡椎体変形率と腰椎QCT値の間の強い相関関係が確認され,椎体変形者全体の50%はQCT値70mg/cm(3)以下に分布し,90%は125mg/cm(3)以下に分布した｡さらに,この70mg/cm(3)付近での椎体変形者の割合は50%であり,125mg/cm(3)付近での椎体変形の割合は10%であった｡QCTによる腰椎海綿骨骨塩量測定値は,腰椎の変形および骨折の危険性を予 測する良好な指標であることが確認できた｡

In 360 females, Bone mineral density (BMD) in lumbar vertebrae (L2-L4) was assessed by quantitative computed tomography (QCT), and the values obtained were compared with the frequency of vertebral transformation or fracture as assessed by lateral scan image (scanogram) by X-ray CT. A correlation was observed between the frequency of vertebral transformation (or fracture) and lumbar BMD values : BMD under 125mg/cm(3) was observed over 90% of women with vertebral transformation, and BMD under 70mg/cm(3) was found about 50% of them. These results suggest that decrease in BMD in lumbar vertebrae leads to vertebral transformation or fracture. Thus, measurement of BMD by QCT would be very useful in predicting vertebral transformation or fractures.