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Updated: Feb 5, 2026

Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Median Nerve Ultrasonography Measurements Correlate With Electrodiagnostic Carpal Tunnel Syndrome Severity
Beverlie L Ting1, Philip E Blazar, Jamie E Collins
1From the Department of Orthopedic Surgery (Dr. Ting, Dr. Blazar, Dr. Collins, Ms. Mora, and Dr. Earp), and the Department of Neurology (Dr. Salajegheh and Dr. Amato), Brigham and Women's Hospital, Boston, MA.
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.
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