用于全髋关节置换术后康复与助残辅助假肢的设计

Design of rehabilitation and disability assisted prosthesis for total hip arthroplasty

目的研究与设计用于全髋关节置换术后的康复与助残辅助假肢。方法利用术前CT图片重建患者股骨三维模型,基于术后的X线片,利用图像处理方法获得植入假体与假体模型之间的配准。借助于有限元分析方法获得假体在髓腔中固定所需的加载力。当足底力传感器监测到行走的力达到设定的加载力时,辅助假肢动作,替换人腿传递行走力,控制足底力小于设定值。结果对于20%体重、40%体重、60%体重和80%体重的设定值,辅助假肢控制的足底行走力最大超出值为22.83 N,超出值的平均值与体重的比值分别为1.5%、1.49%、1.25%和0.52%。提示辅助假肢控制的足底行走力的设定值越大越有利于人在主观上对其行走力进行控制。结论此辅助假肢有助于改善力的传导,易于促进骨长入,利于术后康复。

Objective To study a novel design of rehabilitation and disability assistant prosthetics after total hip arthroplasty.Methods The three-dimensional model of the patient’s femur was reconstructed using preoperative CT images. Based on the postoperative X-ray images,the registration between the implanted prosthesis and the prosthesis model was obtained by image processing. The finite element analysis method was used to obtain the required loading force of the prosthesis in the medullary cavity. When the plantar force sensor to detect the walking force reaches the set load force,the auxiliary prosthesis action,replace the human leg transmission of walking force,control the plantar force was less than the set value. Auxiliary prosthetic arc rotation structure ensured that the transmission of walking force pointed to the center of gravity and ensured the stability of walking.Results The maximum value of walking force of auxiliary prosthesis control was 22.83 N. For the set values of 20%,40%,60% and 80% of the body weight,the ratio of the average overweight value to body weight was 1.5%,1.49%,1.25% and 0.52%,respectively. With the increase of the set value,its exceeding value became smaller,indicating the advantagefor patients to control their walking force subjectively as the larger the set value.Conclusion This design of the auxiliary prosthesis improves the strength conduction and facilitates post-operative rehabilitation.