长骨裂纹宽度和角度对低阶超声导波的影响

Using ultrasonic guided wave to assess long bone fractures and fracture healing has become a promising diagnostic issue. But the multiple guided wave modes alias has always been a big challenge. To solve this problem, a low frequency signal is used in the two-dimension finite-difference time-domain (2D-FDTD) simulation and only S0 and A0 modes are excited. The amplitude of guided waves S0 and A0 in long bone with different fracture width and angle are analyzed. The results show that both S0 and A0 amplitudes decrease with the increasing of fracture width in different oblique fracture angle. A0 amplitude increases with the increasing of oblique fracture angle while S0 amplitude decreases with the increasing of fracture angle then increase with the further increasing of fracture angle with a turning point at around 45 . The ratio parameter between the amplitude of S0 and A0 can evaluate the change of fracture width in different fracture angle cases. Thus, it can provide basis for evaluating fractured long bone with vertical and oblique angle, and monitoring the healing of fractured long bone.