Correlation of Median Nerve Thickness to Its Conduction Velocity in Carpal Tunnel Syndrome
M. G. Ullas Gowda, Madhukesh Rudramurthy, V. Sheshagiri, MruthyunjayaAbstract
Introduction:
Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper limb. CTS is known to be progressive, and more rapid progression is observed if associated with comorbidities. Nerve conduction studies (NCSs) are commonly used for the diagnosis. Ultrasonography (USG) is a real-time tool and a noninvasive method for diagnosing CTS. This study was done to assess the correlation of the median nerve thickness measured by USG with that of the severity scale measured by nerve conduction velocity studies in CTS.
Methodology:
All individuals aged above 18 years who were diagnosed as a case of CTS were included in the study. NCS of the bilateral upper limb was done, and USG of the median nerve of the affected limb was done for each patient.
Results:
A total of 64 patients were included in the study, with 116 CTS cases. There was a positive correlation between USG measurements of the median nerve and NCS grading with
Conclusion:
USG of the median nerve showed a significant correlation of the median nerve thickness and cross-sectional area (of wrist and wrist/forearm ratio) to its conduction velocity (graded by NCSs) in moderate-to-severe type of disease. Moreover, USG also identified local pathology at the wrist joint, including median nerve morphological changes and anatomical variations of the carpal tunnel.