Optimizing and standardizing quantitative EMG.

Quantitative EMG (QEMG) is a useful technique to diagnose subtle neuromuscular disorders. Automated QEMG techniques rely upon computer algorithms to extract motor unit action potentials (MUAPs). A number of different algorithms are available and we have compared the performance of three of them. We have also assessed a number of variables related to the operations performed by the algorithms, including marking of MUAP metrics, data acquisitions time, and effects of raising the high-pass filter. We have also assessed whether there are differences in MUAP metrics depending upon where the needle is placed in the muscle.