Spinal cord injury (SCI) is associated with bone fragility and fractures around the knee. The purpose of this investigation was to validate a computed tomography (CT) based finite element (FE) model of the proximal tibia and distal femur under biaxial loading, and to retrospectively quantify the relationship between model predictions and fracture incidence. Twenty-six cadaveric tibiae and femora (n = 13 each) were loaded to 300 N of compression, then internally rotated until failure. FE predictions of torsional stiffness (K) and strength (T_ult) explained 74% (n = 26) and 93% (n = 7) of the variation in experimental measurements, respectively. Univariate analysis and logistic regression were subsequently used to determine if FE predictions and radiographic measurements from CT and dual energy X-ray absorptiometry (DXA) were associated with prevalent lower-limb fracture in 50 individuals with SCI (n = 14 fractures). FE and CT measures, but not DXA, were lower in individuals with fracture. FE predictions of T_ult at the tibia demonstrated the highest odds ratio (4.98; p = 0.006) and receiver operating characteristic (0.84; p = 0.008) but did not significantly outperform other metrics. In conclusion, CT-based FE model predictions were associated with prevalent fracture risk after SCI; this technique could be a powerful tool in future clinical research.

脊髓损伤 (SCI) 与膝关节周围的骨脆性和骨折有关。本研究的目的是验证双轴载荷下胫骨近端和股骨远端的基于计算机断层扫描 (CT) 的有限元 (FE) 模型，并回顾性量化模型预测与骨折发生率之间的关系。26 个尸体胫骨和股骨（ 每个n = 13）被加载到 300 N 的压缩力，然后内部旋转直到失败。扭转刚度 ( K ) 和强度 ( T _ult ) 的有限元预测解释了 74% ( n  = 26) 和 93% ( n = 7) 分别为实验测量值的变化。随后使用单变量分析和逻辑回归来确定来自 CT 和双能 X 射线吸收测定法 (DXA) 的 FE 预测和放射学测量是否与 50 名 SCI 患者（n  = 14 次骨折）的普遍下肢骨折有关。骨折个体的 FE 和 CT 测量值较低，但 DXA 测量值较低。胫骨T _{ult 的}FE 预测显示出最高的优势比 (4.98; p  = 0.006) 和接收器操作特征 (0.84; p = 0.008) 但并未明显优于其他指标。总之，基于 CT 的 FE 模型预测与 SCI 后普遍存在的骨折风险相关；这项技术可能成为未来临床研究的有力工具。