Wardlaw D, McLauchlan J, Pratt D J, Bowker P
J Bone Joint Surg Br. 1981 Feb;63-B(1):7-11. doi: 10.1302/0301-620X.63B1.7204477.
The off-loading characteristics of the cast-braces of 30 patients with fractures of the shaft of the femur have been investigated, during axial loading, using strain-gauge transducers. These were applied at the level of the fracture, where the cast was circumferentially split, and to the hinges of the brace at the knee. They measured the load transferred between the two portions of the thigh cast, and between the thigh cast as a whole and the below-knee cast; by subtraction from the total load on the limb, the skeletal force at the fracture level and at the knee could be calculated. In all patients there was an increase in the fracture load as union progressed which was thought to be due to physiological feedback mechanism from the fracture site. The load carried by the two portions of the thigh cast and by the thigh cast as a whole was proportionately high at first and stabilised at an average of 35 per cent of body weight.
使用应变片传感器对30例股骨干骨折患者的石膏支具在轴向加载过程中的卸载特性进行了研究。应变片贴于骨折水平处（此处石膏沿圆周方向切开）以及支具在膝关节处的铰链上。它们测量了大腿石膏两部分之间以及整个大腿石膏与膝下石膏之间传递的载荷；通过从肢体总载荷中减去这些载荷，可计算出骨折水平和膝关节处的骨骼受力。在所有患者中，随着骨折愈合，骨折载荷均增加，这被认为是由于骨折部位的生理反馈机制所致。大腿石膏两部分以及整个大腿石膏所承载的载荷起初比例较高，最终稳定在平均体重的35%。
