10 April 2026 : Review article
Carpal Tunnel Syndrome Diagnosis: A Narrative Review of Complementary Roles of Neuromuscular Ultrasound and Electrodiagnostic Studies
Yumeng Dong AEF 1, Yunrui Zhuang AEF 2*, Lingmei Li BDF 2, Yanduo Li BC 2, Huiyan Dai DF 3DOI: 10.12659/MSM.952034
Med Sci Monit 2026; 32:e952034
Table 3 Proposed integrated diagnostic strategy for CTS.
| Diagnostic stage | Action | Role of NMUS (anatomical) | Role of EDX (physiological) | Clinical rationale |
|---|---|---|---|---|
| Step 1: Initial screening | Clinical history + Physical exam (eg, CTS-6) + NMUS | Primary screen: Assess CSA (≥10 mm2), nerve mobility, and anatomical variants (eg, bifid nerve) | Deferred (unless immediate red flags for polyneuropathy exist) | NMUS provides a rapid, non-invasive, and patient-friendly screen to confirm median nerve swelling |
| Step 2: Confirmation & grading | EDX | Adjunct: Used if anatomical cause is unclear or structural lesion is suspected (cyst/tumor) | Gold standard: Quantify DML and SCV to grade severity (mild/moderate/severe) | EDX is required to objectively quantify functional loss, which NMUS cannot accurately grade |
| Step 3: Complex/ discrepant cases | Combined modalities | Rule out structural causes: Identify tenosynovitis or dynamic compression not seen on EDX | Differential diagnosis: Distinguish CTS from cervical radiculopathy or polyneuropathy (eg, in diabetes) | Essential when clinical signs mismatch imaging (eg, False − NMUS/True + EDX) or to rule out “double crush” syndrome |
| Step 4: Treatment planning | Data synthesis | Guidance: Pre-operative mapping of anatomy; guidance for injection therapy | Prognosis: Establish baseline conduction values to monitor post-treatment recovery | Utilizing NMUS for safe intervention targeting and EDX for longitudinal functional monitoring |
| CTS – carpal tunnel syndrome; CTS-6 – CTS-6 clinical prediction rule; CSA – cross-sectional area; DML – distal motor latency; EDX – electrodiagnostic studies; NMUS – neuromuscular ultrasound; SCV – sensory conduction velocity. | ||||