The Value of Electrodiagnostic Studies in Diagnosis and  Management of Neuromuscular Disorders:  A Retrospective Study from a Tertiary-Care Hospital in Thailand

Rachawan Suksathien

Authors

Rachawan Suksathien Department of Rehabilitation Medicine, Maharat Nakhon Ratchasima, Meaung, Nakhon Ratchasima, 30000

Keywords:

electrodiagnosis, electromyography, neuromuscular diseases

Abstract

Objectives: To evaluate the value of electrodiagnostic studies (EDx) in diagnosis and management of neuromuscular disorders.

Study design: Retrospective study.

Setting: Maharat Nakhon Ratchasima Hospital, Nakhon Ratcha-sima, Thailand.

Subjects: New patients who were referred to EDx laboratory, Maharat Nakhon Ratchasima Hospital between January 1, 2019 and December 31, 2020.

Methods: General demographics, referring physician specialty, referral diagnosis, diagnosis after EDx, impact of EDx on diagnosis and management were reviewed retrospectively. The impact of EDx was classified into confirmed, changed, and no added value. Management by referring specialists after receiving EDx reports including investigation, consultation and treatment were recorded. The association between variables and change in diagnosis and management after EDx, were analyzed using
multivariable analysis.

Results: Of 856 patients, the diagnosis was changed and confirmed after EDx in 28.4% and 69.3% respectively. EDx results led to a change in management for 29%. Referral diagnosis of radiculopathy, no referral diagnosis, female patient and neurologists’ referral were major contributing factors to a change in diagnosis with odds ratios (95% CI) of 3.67 (1.52, 8.85), 2.61 (1.44, 4.73), 1.79 (1.23, 2.56) and 1.79 (1.20, 2.67) respectively. While referral diagnosis of neuromuscular junction (NMJ) disease,
motor neuron disease (MND) and referred by orthopedic surgeons were the top three variables correlated with a change in management with odds ratios (95% CI) of 3.81 (1.8, 8.08), 2.85 (1.11, 7.37) and 2.24 (1.2, 4.2) respectively.

Conclusions: EDx is a valuable investigation that confirms (69.3%) or changes (28.4%) the diagnosis and guides the appropriate management (29%) in patients with neuromuscular disorders.

Keywords: electrodiagnosis, electromyography, neuromuscular diseases

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