Dai Ya-Hui, Qin Tao
Department of Orthopaedics Surgery, Songjiang District Central Hospital, Shanghai 201600, China.
Zhongguo Gu Shang. 2023 Mar 25;36(3):251-5. doi: 10.12200/j.issn.1003-0034.2023.03.011.
To investigate the biomechanical characteristics of retinaculum in the treatment of femoral neck fractures.
The CT data of a 75-year-old female volunteer was processed by software to construct an intact femur model and femoral neck fracture model fixed with three cannulated screws, which were divided into models with retinaculum or not. The Von-Mises stress distribution and displacement were compared to analyze the stability differences between the different models to study the mechanical characteristics of the retinaculum in the treatment of femoral neck fractures.
In the intact femur, the most obvious displacement appeared in the weight-bearing area of the femoral head, with retinaculum 0.381 37 mm, and without retinaculum 0.381 68 mm. The most concentrated part of the Von-Mises stress distribution was located in the medial and inferior part of the femoral neck, with retinaculum 11.80 MPa, without retinaculum 11.91 MPa. In the femoral neck fracture fixed with three cannulated screws model, the most obvious position of displacement also appeared in the weight-bearing area of the femoral head, with retinaculum 0.457 27 mm, without retinaculum 0.458 63 mm. The most concentrated part of the Von-Mises located at the medical and inferior part of the femoral neck, with retinaculum 59.22 MPa, without retinaculum 59.14 MPa. For the cannulated screws, the Von-Mises force peaks all appeared in the posterior and superior screw, with retinaculum 107.48 MPa, without retinaculum 110.84 MPa. Among the three screws, the Von-Mises stress of the anterior-superior screw was the smallest, which was 67.88 MPa vs 68.76 MPa in the retinaculum and non-retinaculum groups, respectively.
The complete retinaculum has little effect on the stability of intact femur and femoral neck fractures with anatomical reduction after internal fixation, and cannot effectively improve the stability of the fracture end after the fracture.
探讨支持带在股骨颈骨折治疗中的生物力学特性。
利用软件对一名75岁女性志愿者的CT数据进行处理，构建完整股骨模型及用三枚空心钉固定的股骨颈骨折模型，分为带支持带和不带支持带模型。比较Von-Mises应力分布及位移情况，分析不同模型间的稳定性差异，以研究支持带在股骨颈骨折治疗中的力学特性。
在完整股骨中，股骨头负重区位移最明显，带支持带为0.381 37 mm，不带支持带为0.381 68 mm。Von-Mises应力分布最集中部位位于股骨颈内侧及下方，带支持带为11.80 MPa，不带支持带为11.91 MPa。在三枚空心钉固定的股骨颈骨折模型中，位移最明显位置同样出现在股骨头负重区，带支持带为0.457 27 mm，不带支持带为0.458 63 mm。Von-Mises应力最集中部位位于股骨颈内侧及下方，带支持带为59.22 MPa，不带支持带为59.14 MPa。对于空心钉，Von-Mises力峰值均出现在后上方螺钉，带支持带为107.48 MPa，不带支持带为110.84 MPa。在三枚螺钉中，前上方螺钉的Von-Mises应力最小，支持带组和非支持带组分别为67.88 MPa和68.76 MPa。
完整的支持带对完整股骨及内固定后解剖复位的股骨颈骨折稳定性影响较小，骨折后不能有效提高骨折端稳定性。
