Saffarzadeh Mona, Hightower R Caresse, Talton Jennifer W, Miller Anna N, Stitzel Joel D, Weaver Ashley A
a Virginia Tech-Wake Forest University Center for Injury Biomechanics , Winston-Salem , North Carolina.
b Wake Forest School of Medicine , Winston-Salem , North Carolina.
Traffic Inj Prev. 2016 Sep;17 Suppl 1:34-41. doi: 10.1080/15389588.2016.1203429.
This study aimed to quantify lumbar volumetric bone mineral density (vBMD) for 873 seriously injured Crash Injury Research and Engineering Network (CIREN) motor vehicle crash occupants (372 male, 501 female) from 8 centers using phantomless computed tomography scans and to associate vBMD with age, fracture incidence, and osteopenia/osteoporosis diagnoses. The novelty of this work is that it associates vBMD with region of injury by applying an established method for vBMD measurement using phantomless computed tomography (CT).
A validated phantomless CT calibration method that uses patient-specific fat and muscle measurements to calibrate vBMD measured from the L1-L5 trabeculae was applied on 873 occupants from various CIREN centers. CT-measured lumbar vBMD < 145 mg/cc is indicative of osteopenia using a published threshold. CIREN occupant lumbar vBMD in milligrams per cubic centimeter was regressed against age, osteopenia/osteoporosis comorbidities, height, weight, body mass index (BMI), and the incidence of fracture in vertebral (cervical, thoracic, lumbar) and rib/sternum regions.
Among the 873 occupants analyzed, 11% (92 occupants) were diagnosed as osteopenic in CIREN. Of these 92 occupants, 42% (39 occupants) had normal vBMD measures (≥145 mg/cc), suggesting possible misclassification in CIREN. Of the 134 occupants classified as osteopenic in vBMD analysis, 60% were not classified as osteopenic in CIREN, suggesting undiagnosed osteopenia, and 40% were correctly classified in CIREN. Age was negatively correlated with vBMD (P <.0001) and occupants with <145 mg/cc vBMD sustained a median number of 2 rib/sternum fractures compared to a median value of 0 rib/sternum fractures for the ≥145 mg/cc vBMD group (P <.0001). Vertebral fracture analysis revealed that the thoracolumbar region was the most common region of injury in the spine. Though the incidence of fracture was not significantly different in the thoracic (10% versus 6%, P =.122) and lumbar (16% versus 13%, P =.227) regions between the 2 bone quality groups, the proportion of thoracolumbar fractures was significantly higher in occupants with <145 mg/cc vBMD versus occupants with ≥145 mg/cc vBMD (24% versus 17%, P =.043).
Low lumbar vertebral bone quality is associated with an increased number of rib/sternum fractures and a greater incidence of thoracolumbar vertebral body fractures within the CIREN population analyzed.
本研究旨在利用无体模计算机断层扫描，对来自8个中心的873名严重受伤的碰撞损伤研究与工程网络（CIREN）机动车碰撞驾乘人员（372名男性，501名女性）的腰椎体积骨密度（vBMD）进行量化，并将vBMD与年龄、骨折发生率以及骨质减少/骨质疏松诊断相关联。本研究的新颖之处在于，通过应用一种既定的使用无体模计算机断层扫描（CT）测量vBMD的方法，将vBMD与损伤区域相关联。
一种经过验证的无体模CT校准方法被应用于来自CIREN各中心的873名驾乘人员，该方法使用患者特定的脂肪和肌肉测量值来校准从L1 - L5小梁测量的vBMD。根据已发表的阈值，CT测量的腰椎vBMD < 145 mg/cc表明存在骨质减少。以每立方厘米毫克为单位的CIREN驾乘人员腰椎vBMD与年龄、骨质减少/骨质疏松合并症、身高、体重、体重指数（BMI）以及椎体（颈椎、胸椎、腰椎）和肋骨/胸骨区域的骨折发生率进行回归分析。
在分析的873名驾乘人员中，CIREN诊断出11%（92名驾乘人员）患有骨质减少。在这92名驾乘人员中，42%（39名驾乘人员）的vBMD测量值正常（≥145 mg/cc），这表明CIREN中可能存在分类错误。在vBMD分析中被归类为骨质减少的134名驾乘人员中，60%在CIREN中未被归类为骨质减少，这表明存在未被诊断出的骨质减少，40%在CIREN中被正确分类。年龄与vBMD呈负相关（P <.0001），vBMD < 145 mg/cc的驾乘人员肋骨/胸骨骨折的中位数为2例，而vBMD≥145 mg/cc组的肋骨/胸骨骨折中位数为0例（P <.0001）。椎体骨折分析显示，胸腰段是脊柱最常见的损伤区域。尽管在两个骨质质量组中，胸椎（10%对6%，P =.122）和腰椎（16%对13%，P =.227）区域的骨折发生率没有显著差异，但vBMD < 145 mg/cc的驾乘人员胸腰椎骨折的比例显著高于vBMD≥145 mg/cc的驾乘人员（24%对17%，P =.043）。
在所分析的CIREN人群中，腰椎椎体骨质质量低与肋骨/胸骨骨折数量增加以及胸腰椎椎体骨折发生率较高相关。
