腰椎正位DXA影像形态学特征及腰椎标序方法

Lumbar vertebrae morphological characteristics and vertebrae identification approach in lumbar spine DXA images

目的对腰椎正位双能X线吸收测量仪(dual-energy X-ray absorptiometry,DXA)影像进行形态学测量分析,并对腰椎标序方法进行研究。方法本研究纳入的成人腰椎正位DXA影像:测量左、右椎弓根中点及棘突末端中点连线所形成的角度及其变化规律;观察并记录最低位肋骨出现位置、腰椎最长横突出现位置、L4轮廓是否呈“H”形及双侧髂嵴上缘连线位置。结果本研究共纳入2361例腰椎正位DXA影像,平均年龄(53.8±12.6)岁,女性占78.8%。腰椎正位DXA影像中L1-L5双侧椎弓根中点与棘突末端中点的连线所形成的角度由上向下逐渐增大,且在L1-L4中呈“V”字形,在L5呈“一”字形。最低位肋骨以T12最为常见(2002例,84.8%)。最长横突以L3椎体最常见(1480例,62.7%)。双侧髂嵴上缘连线以L4-L5椎间隙最为常见(1822例,77.2%)。腰椎DXA影像中“H”形L4共1759例(74.5%)。结论本研究提出的L1-L4“V”字征及L5“一”字征标序方法不受骨质增生影响,且简明形象,易于接受,该方法的提出更有助于腰椎DXA标序,为骨密度准确测量奠定基础。

Objective To analyze the morphologic characteristics of lumbar vertebrae in dual-energy X-ray absorptiometry(DXA)images and to study the identification methods of lumbar spine.Methods Lumbar spine DXA images from adult patients were reviewed retrospectively.Data were measured and collected regarding key anatomic features seen on DXA:the changes of the angles at the vertex of the two virtual lines connecting the central spinal process with the bilateral pedicles from L1 to L5;the lowest vertebra with ribs;positions of the longest transverse process;the proportion of patients presenting with“H”-shaped L4;and the positions of the most superior portions of the iliac crests.Results DXA images from 2361 patients(78.8%female)were evaluated.The mean age of patients was(53.8±12.6)years old.The angles at the vertex of the two virtual lines connecting the central spinal process with the bilateral pedicles increased from L1 to L5.We call them“V”-shaped L1-L4 and“—”-shaped L5.The lowest ribs were most frequently(2002 patients,84.8%)observed at T12.Totally 1480(62.7%)individuals had the longest transverse processes at L3.A horizontal line drawn across the superior-most portions of the iliac crests crossed the disk space between L4 and L5 among 1882(77.2%)patients.L4 was predominantly“H”-shaped(1759 patients,74.5%).Conclusions The method,“V”-shaped L1-L4 and“—”-shaped L5,presented in this study is simple and easy to accept,and is not affected by hyperosteogeny.This method is helpful for lumbar DXA sequencing and lays a foundation for accurate measurement of bone mineral density.