Faculty Collaboration Database

Quantitative EMG in inflammatory myopathy. Muscle Nerve 1990 Mar;13(3):247-53

Date

03/01/1990

Pubmed ID

2320046

DOI

10.1002/mus.880130312

Scopus ID

2-s2.0-0025214606 (requires institutional sign-in at Scopus site)   57 Citations

Abstract

Fifty-four quantitative electromyographic (EMG) studies were made in 37 patients with inflammatory myopathy (IM) at different points in their clinical course and treatment. All studies were performed in the biceps brachii which varied in clinical strength. Motor unit action potentials (MUAPs) in 45 studies and EMG interference pattern (IP) in 48 studies were recorded using a concentric needle electrode. Macroelectromyographic (Macro-EMG) MUAPs were recorded from 10 patients in 14 studies. MUAP analysis revealed a myopathic pattern (decreased duration and/or area: amplitude ratio) in 69% of studies. IP analysis was more sensitive than MUAP analysis, demonstrating a myopathic pattern in 83% of studies. Macro-EMG MUAP amplitudes were reduced in two studies, minimally increased in one study and normal in the remainder; in 6 (40%) studies, fiber density was slightly increased. Thus, reinnervation does not seem to play an important role in motor unit remodeling in IM.

Author List

Barkhaus PE, Nandedkar SD, Sanders DB

Author

Paul E. Barkhaus MD Professor in the Neurology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Action Potentials
Adult
Aged
Biopsy
Dermatomyositis
Electromyography
Female
Humans
Male
Middle Aged
Muscles
Myositis
Retrospective Studies