| Summary: | 碩士 === 中原大學 === 醫學工程學系 === 85 === Currently, the aseptic loosening is one of the most common complication in the total hip arthroplasty (THA). The purpose of this research is to develop a non-invasive sonic vibration technique measurement system to study the bonding variety between the femur and the implant cementless stem after operation, and its consequent clinical tracing. Dynamic signal analyzer was used to collect and set up the data base of sonic vibration resonant signal. There are three directions of clinical research. Firstly, a non-invasive sonic vibration measurement system was applied to select the data (before the operation, 6 weeks, 3 months, and 5 months after the operation). The changes of the resonant frequency within the operated femurs were measured and doctors' judgments were also consulted to find out the bonding variety of hip prosthesis shown by the quantity of the coefficient of variance (CV) at various times after the operation. If the bonding is not ideal or its quality changes, this composite system reflects the shifting of the peak value of the resonant frequency. Then, we studied the relation between supine position and lateral position of the patient in the measurement system. Finally, we studied the influence of the percent of fat of human subjects.The results show that after the operation, the resonant frequency of the patients' stem-femur composite system is 10 Hz lower than that before. The resonant frequency and CV value measured in the third and the fifth month show no significant statistical difference. It means that the hip prosthesis- femur composite system approaches steady after 3 months of operation. This result is the same as that of clinical evaluation. Lateral position get larger amplitude of the vibration signals but smaller CV value then supine position. It showed that the effectiveness of soft tissue is smaller when we used the pose of lateral position.
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