1998 年 64 巻 625 号 p. 2423-2428
External fixation technique is a convenient treatment for wide clinical use such as bone fracture. In this treatment, it is important to make decision when the external fixation device is detached and the patient start rehabilitation, in order to achieve early healing. Evaluation techniques for bone healing level can offer useful suggestions to the doctor making decision. Thus, we develop an evaluation method of mechanical properties of callus on bone fracture fixed by external fixator. In the method, strains are measured using strain gauges which are attached to some parts of the fixator fixing bone fracture with a certain loading. The strains are inputted to a mathematical or computational model of the fixator and bone, then the callus properties are evaluated inversely. We consider a case of transverse plane fracture of human tibia with external fixator, and apply the evaluation method using an experimental model, a finite element model and a model based on beam theory. Efficiency of the proposed method is discussed from the results.