Department of Clinical Medicine, Jining Medical University, No. 133, Hehua Road, Taibai Lake New District, Jining City, Shandong Province, 272067, China.
Department of Orthopedic, Affiliated Hospital of Jining Medical University, No. 89, Guhuai Road, Jining City, Shandong Province, 272029, China.
BMC Musculoskelet Disord. 2024 Oct 28;25(1):857. doi: 10.1186/s12891-024-07990-1.
This study aims to analyze the differences in mechanical stability of OTA/AO 31A1.3 intertrochanteric fractures under various reduction conditions.
Twenty standard synbone artificial femur test bones were selected for the OTA/AO 31A1.3 intertrochanteric fracture model. The models were divided into five groups according to their reduction state: positive support, neutral support, negative support, varus fixation, and valgus fixation, with four specimens in each group. All models were fixed using PFNA intramedullary fixation and subjected to static axial compression tests. The subsidence displacement of the proximal femur under different loads and the axial stiffness of the model were measured to verify the mechanical stability of the OTA/AO 31A1.3 intertrochanteric fracture under different reduction conditions.
After the static axial compression test, the proximal femoral subsidence displacement in the positive support and neutral support groups was lower than that in the negative support, valgus fixation, and varus fixation groups (p < 0.001). The axial stiffness of the model was highest in the positive support group. Significant differences in subsidence displacement and axial stiffness were found between the groups (p < 0.001). The positive support group demonstrated the best mechanical stability, while the varus fixation group showed the poorest performance.
Positive support of the medial cortex can be regarded as the best reduction state for OTA/AO 31A1.3 intertrochanteric fractures, suggesting that this approach should be preferred during surgery to enhance mechanical stability and improve clinical outcomes. Conversely, varus fixation should be avoided due to its inferior stability.
本研究旨在分析不同复位条件下 OTA/AO 31A1.3 股骨转子间骨折的机械稳定性差异。
选择 20 个标准 Synbone 人工股骨测试骨，建立 OTA/AO 31A1.3 股骨转子间骨折模型。根据复位状态将模型分为正支撑、中和支撑、负支撑、内翻固定和外翻固定 5 组，每组 4 个标本。所有模型均采用 PFNA 髓内固定，并进行静态轴向压缩试验。测量不同载荷下股骨近端下沉位移和模型轴向刚度，以验证不同复位条件下 OTA/AO 31A1.3 股骨转子间骨折的机械稳定性。
在静态轴向压缩试验后，正支撑和中和支撑组的股骨近端下沉位移均低于负支撑、外翻固定和内翻固定组（p<0.001）。正支撑组模型的轴向刚度最高。各组间下沉位移和轴向刚度差异均有统计学意义（p<0.001）。正支撑组表现出最佳的机械稳定性，而内翻固定组表现出最差的稳定性。
内侧皮质的正支撑可视为 OTA/AO 31A1.3 股骨转子间骨折的最佳复位状态，提示在手术中应优先采用这种方法，以增强机械稳定性，改善临床效果。相反，应避免内翻固定，因其稳定性较差。
