1.天津市天津医院 / 天津大学天津医院;2.天津市天津医院 / 天津大学天津医院 骨科研究所
目的 利用生物力学研究方法探究股骨颈骨折术后不同复位质量的力学特性。方法 选用SAWBONES人工合成股骨模型3例，将2例造模成为Pauwell III 型股骨颈骨折，并在骨折模型上以倒三角方式置入3颗空心螺钉，用以固定骨折；并保持不同复位质量（定义为模型1和模型2）；另外1例模型为无骨折模型，即不进行任何造模操作（定义为模型0）；最后在力学试验机上对股骨模型进行垂直载荷加载。结果 当股骨头位移达到4mm时，模型0-模型2承受的平均载荷分别为236.30±5.35N，196.57±3.56N，69.50±2.95N；三组载荷之间具有显著性差异。当股骨头位移达到5mm时，模型0-模型2承受的平均载荷分别为276.7±3.40N，232.93±2.64N，80.83±4.54N，经统计学分析，三组载荷之间具有显著性差异。结论 当股骨头因承受外加载荷产生相同位移时，股骨颈骨折术后残留空间移位较大的股骨头，承受的载荷最小；而无空间移位股骨头模型，承受的载荷最大。说明股骨颈骨折术后复位质量越差，股骨承受应力的能力越弱，术后康复过程中并发骨不愈合、再骨折、股骨头坏死的机率越高。
0bjective To investigate the biomechanical characteristics of different quality of reduction on the rehabilitation of femoral neck fracture. Methods Three cases of SAWBONES artificial femoral models were used, and two cases of Pauwell III femoral neck fracture were modeled. Three cannulated screws were inserted into the models in the form of inverted triangle to fix the fracture. And the two cases maintained different reduction quality (defined as model 1 and model 2). In another case, no modeling operation was performed (defined as model 0). Then the strain gauges were respectively pasted on the regions of interest of the 3 femoral models. Finally, the femur model was loaded with vertical load on the mechanical testing machine. Results When the displacement of femoral head reached 4mm, the average load of model 0, model 1 and model 2 was 236.30 ± 5.35N, 196.57 ± 3.56N and 69.50 ± 2.95N respectively. After statistical analysis, the average load of the three groups of models were significantly different. When the displacement of femoral head reached 5mm, the average load of model 0, model 1 and model 2 was 276.7 ± 3.40N, 232.93 ± 2.64N, and 80.83 ± 4.54N. There was significant difference among the three groups. Conclusion When the femoral head has the same displacement, the greater the residual displacement of femoral neck fracture, the smaller the load on femur; while the model of the femoral head without space displacement, the load is the largest., , which indicates that the lower the quality of the reduction of the femoral neck fracture,the weaker the ability of femur to bear stress, the higher the probability of nonunion, re-fracture and femoral head necrosis in the process of postoperative rehabilitation.