Abstract:
The basic assumption made by the designers of EMG amplifier systems is that the
substantial difference between different person's detected EMG signals is the energy
generated, but the spectral content is sufficiently similar to be ignored. Anecdotally,
there is little or no expectation that there is any structural difference between the
muscles of persons with congenital absence and those with an amputation, although
newer evidence suggests this is untrue [1]. This approximation works well for simple
amplifier/detector systems that were common a decade past [2], but with the
increasing availability of compact on-line processing devices and the increase in
differing EMG processing schemes this approximation is likely to prove unreliable [3].
This study was made with persons who attended the Oxford Limb Fitting Centre at
the Nuffield Orthopaedic Centre, Hospital in Oxford UK, from 1989 to 2001 as part of
a program looking at novel means of processing, and the analysis of EMGs [4,5]. It
sought to understand the variability of the results as they were derived from the
techniques applied (Fuzzy logic, Neural Networks and Wavelet transforms). While
undertaking the study the new information from the structural studies in Texas [1],
showed that it was a worthwhile exercise, and one likely to produce unexpected
results.
