Consistency of the results of neurophysiological examinations with clinical diagnosis formed by the referring physician in ambulatory medical care

Purpose
Access to electroneurographic/electromyographic (ENG/EMG) examinations and the number of patients referred for electrodiagnostic (EDX) examination are increasing. We aimed to determine the accuracy of the initial clinical diagnosis made by outpatient medical care physicians who referred patients to the EMG laboratory.

Methods
We analyzed referrals and EDX results of all patients who visited EMG laboratory of the Department of Clinical Neurophysiology, Institute of Psychiatry and Neurology in Warsaw in 2021. Examinations were performed in accordance with the standards and norms adopted in our laboratory by EMG-certified neurologists, regarding the initial diagnosis stated by referring physicians.

Results
A total of 454 EDX results from 412 patients were analyzed. Most of patients (54.6%) were referred with diagnosis of carpal tunnel syndrome (CTS), followed by single nerves damage (18.7%), polyneuropathy (18.1%), tetany (7.0%), myasthenia gravis (1.3%) or myopathy (0.2%). The result of the ENG/EMG examination was: diagnosis confirmation (61.9%), a new clinically significant diagnosis or additional asymptomatic nerve damage (32.4%), and normal examination result (25.1%) of patients. Electrophysiological examination most often confirmed the referral diagnosis in patients with suspected CTS (75.4%), followed by single nerves damage (51.8%), polyneuropathy (48.8%), tetany (31.3%) and the least for myasthenia gravis and myopathy (0%).

Conclusions
Our study showed frequent inconsistency of the EDX results with the clinical diagnosis formed by the referring physician. A high percentage of  normal test results was noted. Initial diagnosis and the scope of EDX examination should be determined by detailed interview and physical examination.