Myoelectric activity during voluntary elbow movements in above-elbow amputees

This study is concerned with the analysis of myoelectric activity in the biceps and triceps muscles of unilateral above-elbow (AE) amputees during voluntary fast elbow movements. The signal patterns obtained from each subject's remnant limb were analysed and compared with similar acquired muscle patterns from the sound arm. Our findings, in agreement with suggestions from the literature, show that a significant portion of the so-called triphasic muscle patterns still occur in the remnant limbs of amputees, and therefore, are generated without the use of proprioceptive and sensory feedback. Although the patterns show some unexplained inconsistencies in timing and duration, the results indicate that for traumatic amputees the loss of an arm does not mean that remnant muscle contractions lose their relation to previous movements. In addition, congenital amputees did not show phasic patterns during voluntary fast elbow movements.