https://doi.org/10.4081/ejtm.2026.15547
Ultrasonography versus electrodiagnosis of median nerve before and after open carpal tunnel release surgery: which can better diagnose, predict and assess postoperative improvement?
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Accepted: 7 July 2026
Published: 26 August 2026
Diagnosis of Carpal Tunnel Syndrome (CTS) relies on a structured clinical approach with Electrodiagnostic Studies (EDX) accepted as the gold standard in the diagnosis. Yet, Ultrasound (US) has emerged as a non-invasive alternative especially in assessing morphological changes. And so, to accurately diagnose CTS by a valid non-painful simple tool, objectively assess postoperative improvement and finally to predict postoperative clinical outcome from preoperative data; clinical, EDX, and US data were collected, compared and correlated pre- and 1 month postoperative. While US achieved diagnostic accuracy of 80% in CTS diagnosis, particularly Wrist Cross-Sectional Area (wCSA) and Wrist-Forearm Ratio (WFR), it remains less sensitive than EDX. The diagnosis of CTS using wCSA/WFR achieved a sensitivity of 80.0%/80.0% and a specificity of 100%/85.7%, at a cutoff score of 12.5mm2/2.1 or above. In addition, linear regression analysis showed that only compound motor action potential (CMAP) amplitude could predict postoperative clinical improvement. Sensitivity of EDX (93.33%) overcome that of the US in detection of postoperative improvement. US is less sensitive than EDX in diagnosing CTS, assessment and prediction of postoperative clinical outcome.
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Ethics Approval
CRediT authorship contribution
Fatema AlZahraa Ahmad achieved the methodology, collected the data, shared in writing the manuscript and organization of results, Shahira Mahmoud Mostafa plotted the hypothesis, was the research manager, helped in general revision of the manuscript, Eman Ahmad Maher revised the practical and theoretical inputs at each step of the research, helped in organization of the results and in discussion generation, Mostafa Ezzat Mahmoud was responsible for proper selection of the patients, and progress of the clinical part of the research, Aliaa Ali Tawfeek helped in writing and editing the manuscript.
Supporting Agencies
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author.
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