Zdravniški Vestnik (Apr 2003)
CRITICAL ANALYSIS OF REFERRALS TO ELECTRODIAGNOSTIC EXAMINATION OF THE PERIPHERAL NERVOUS SYSTEM
Abstract
Background. Clinical neurophysiologists observe a large number of examinees referred to a electromyographic (EMG) laboratory without clinical symptoms or signs of the peripheral nervous system lesion. Such referrals do not improve management of patients, but only unnecessarily burden examinees and laboratory personnel. The aim of the present study was to check appropriateness of referrals to electrodiagnostic examination, look for reasons for problems and suggest possible improvements.Methods. From the database of the Institute of Clinical Neurophysiology in Ljubljana all examinees evaluated by the author in a »general« EMG laboratory in the first 4 months of 2002 were included. From data about examinees, referral doctors, referral diagnoses, clinical symptoms and signs and electrophysiological findings, predictive values for neurological referral diagnoses and electrodiagnostic abnormalities were calculated using descriptive and multivariate statistical analyses.Results. Three hundred examinees (42% men) were included. Neurological diagnosis was provided in 55% of referrals. Electrodiagnostic abnormalities were found in 45% of examinees (carpal tunnel syndrome 50%, radiculopathy 25%, other mononeuropathies 15%, polineuropathy 9%). In 9% of examinees only clinical, and in 47% neither clinical nor electrodiagnostic abnormalities were demonstrated. Using a multivariate analysis positive effect of referral with neurological diagnosis, of paraesthesiae and findings of weakness and sensory loss, and negative effect of pain and referral diagnosis cervicobrachialgia or lumboischialgia on pathological electrodiagnostic findings were found. Isolated pain and paraesthesiae (with carpal tunnel syndrome excluded) were particularly poor predictors of abnormal electrodiagnostic findings (9% and 16%, respectively). With exception of 20 patients with carpal tunnel syndrome, none with normal clinical neurological examination had abnormal electrodiagnostic findings.Conclusions. Our study confirmed inappropriateness of electrodiagnostic examination as a screening tool for the peripheral nervous system lesions. Inappropriate referrals were due to poor evaluation of examinees before referral, and due to use of electrodiagnosis in screening of patients. We propose electrodiagnostic examination only of patients with unequivocal clinical signs of the peripheral nervous system lesion, and of patients with typical symptoms of the carpal tunnel syndrome. Referrals should include neurological diagnostic question and all relevant clinical data. This would reduce waiting time, save money, and improve evaluation of patients with peripheral nervous system lesions.
