荷重負荷による健常人関節音の検討

抄録

With an acoustical technique, the authors analysed 84 knee joints of normal subjects who were students at University of Occupational and Environmental Health. Inside an anechoic chamber, the sounds were collected from a Brüel & Kjær precision condenser microphones, and analysed by a narrow band spectrum analyzer and computer. The subjects were asked to swing their leg actively or passively at about 90° from 0° flexion as a movement on nonweight bearing. In the weight bearing, they repeated the motion of crouching down and standing up. The motion rate was about 2.3 seconds per a cycle and cotrolled with a very low noise electric leg model. This analysis revealed that weight bearing caused the increase of sound level from 0.5kHz to 1kHz. From this study, we believe that friction noise of normal joints is very small and low frequency components of their sounds are increased.