The purpose of this study was to examine the differences in the wrist-elbow median mixed nerve forearm evoked potential (WEmix) in subjects with severe and chronic carpal tunnel syndrome (CTS) compared to a control sample to identify correlations and predictive relationships between traditional nerve conduction (NCS) measures of CTS and WEmix. Previous research has firmly established that induced axon loss in animals, not demyelination, results in retrograde axonal atrophy (RAA), which is also time-dependent. Slowing of forearm motor conduction velocity (FAMCV) is frequently observed in patients with CTS. It is attributed to either conduction block of the fibers at the wrist or retrograde axonal atrophy. To examine these phenomena, the WEmix was developed to measure the median nerve’s proximal fibers directly. There is controversy regarding WEmix as a measure of RAA in CTS, and there are several methodological considerations that may explain this debate.
