An anatomical and histological narrative of a subcutaneous muscle of the anterior abdominal wall in human cadavers: a case report

Abstract This report investigates a subcutaneous muscle layer found during routine dissections in four formalin embalmed human cadavers donated for medical training. The gross and microscopic morphology is described and potential implications in humans are raised. Tissue samples were taken from representative regions of the anterior abdominal wall and stained using Haematoxylin & Eosin followed by Masson’s Trichrome. The muscle tissue was seen in the deepest layers of the hypodermis of the anterior abdominal wall, with variable presentation between cadavers. Visually, it appeared as a thin greyish-pink or brown layer with variable morphology based on location, namely, sheet like, discontinuous, and enmeshed within fascial layers, with a thickness ranging from 1 to 5 mm. Tissue staining revealed muscle fibres in all samples. Our incidental findings add gross and histological evidence for the presence of a subcutaneous muscle layer found in the anterior abdominal wall of humans.