Abstract
Following a pilot investigation into the basic concepts of vibration and transfer pickup responses, a mechanical measuring system with an electronic velocity feedback for experimentally determining the Input and Transfer impedances of a knee joint are described. The system incorporated commercially available equipment for the excitation , observation, and analysis of measurements. The results for the input and transfer impedances between normal and arthritic subjects are compared. The patterns of the transfer impedance curves between the left and right knees were similar and distinctive for each of the pickup positions, but nevertheless characteristic to each subject. Large differences were observed in the transfer impedance amplitudes through a large frequency span should a subject suffer from arthritis in one knee and the other knee is normal. It is concluded that with the present setup, further studies could be directed to investigating bone porosity, fracture or union of bones and patella disorders.