A Comparison of Handheld Versus Cart-based Ultrasound in the Evaluation and Diagnosis of Carpal Tunnel Syndrome

Background: Carpal tunnel syndrome (CTS) is responsible for over 90 % of median nerve neuropathies. Though a clinical diagnosis, evaluation of nerve conduction via electrodiagnostic studies (EDX) and median nerve cross sectional area (CSA) through sonographic imaging provides supporting evidence and insight into disease severity. The advent of handheld ultrasound devices offers a portable, cost-effective and non-invasive method for median nerve assessment, yet its accuracy compared to traditional cart-based ultrasound has not been assessed in this setting.

Methods: 43 consecutive patients who presented to an outpatient orthopedic clinic within a large academic institution for symptoms consistent with CTS between August 2023 and April 2024 were included. Handheld sonography was performed with the Clarius Convex L20 HD3 8-20 MHz transducer. The GE Venue Go with a 4-20 MHz linear transducer was used for conventional cart-based ultrasound evaluation. A paired -test was performed to compare the mean cross-sectional area (CSA) measured with the GE machine to the mean CSA measured with the Clarius transducer (p < 0.05).

Results: The average CSA measurement obtained with the GE was 14.21 ± 4.89 mm. The average CSA measurement obtained with the Clarius handheld transducer was 13.54 ± 4.50 mm. The mean difference between the GE and Clarius groups was 0.62 mm (95 % CI = -1.47 to 2.71), p = 0.55.

Conclusion: CSA measurements of the median nerve obtained by a handheld ultrasound transducer are comparable to those measured by a traditional cart-based ultrasound machine for carpal tunnel diagnosis. The adoption of handheld ultrasounds in clinical settings holds the potential for quicker, more precise diagnoses and broader access to imaging.