Introduction: The purpose of this study was to assess whether median nerve ultrasonography (US) measurements correlate with the severity scale of electrodiagnostic studies (EDS) of carpal tunnel syndrome (CTS).
Methods: A retrospective review was conducted of patients aged ≥18 years who underwent both median nerve US and EDS. US measurements of the median nerve cross-sectional area at the distal wrist crease and forearm were used to calculate the median nerve wrist-to-forearm ratio. EDS severity was classified according to guidelines from the American Association of Electrodiagnostic Medicine.
Results: A total of 112 wrists (n = 112) in 78 consecutive patients with a mean age of 59 (range, 26 to 88) years were included. Increased cross-sectional area at the distal wrist crease and wrist-to-forearm ratio were significantly correlated with increased EDS severity (P < 0.0001).
Discussion: Median nerve US measurements not only distinguished between normal and abnormal EDS but also correlated with the category of EDS severity.
Level of evidence: Diagnostic III.