An introduction to myopathology: use of skeletal muscle biopsy in the diagnosis of neuromuscular disorders.

Abstract

AbstractSkeletal muscle biopsy (SMB) analysis is an essential part of diagnosing neuromuscular disorders, but its variable presentation, high artefact rate, and limitations can make interpretation difficult. Although genetic testing has reduced the need for invasive biopsy in some disorders (e.g., certain muscular dystrophies), SMB continues to provide critical diagnostic information in congenital and acquired myopathies, including inflammatory myopathies, metabolic and mitochondrial disorders, and diagnostically ambiguous cases. A structured, pattern-based approach to SMB interpretation is essential to ensure that key positive and negative findings are recognised, artefacts are avoided, and findings are integrated with clinical, biochemical, electrophysiological, and imaging data. In this review, we describe the principal histological patterns observed in SMB (neurogenic, myopathic, dystrophic, and inflammatory), along with the clinical contexts in which these patterns are encountered. The review is aimed primarily at histopathology residents and junior consultants.