Quick Facts
The endomysium is the sheath of delicate reticular fibrils that surrounds each muscle fiber (Dorland, 2011).
Related parts of the anatomy
Structure
The endomysium is a delicate sheath of connective tissue which envelopes each individual skeletal muscle fiber, consisting primarily of type III and type IV collagen (Standring, 2016).
Key Features/Anatomical Relations
Endomysium surrounds the individual skeletal muscle fibers within the fascicles and forms their immediate internal environment. The three collagenous sheaths, the epimysium, perimysium, and endomysium unite and fuse where the muscles connect to adjoining structures such as tendons.
Function
The endomysium is the site of metabolic exchange between blood and the skeletal muscle fiber, as it contains capillaries which supply the muscle fiber. As this layer is composed of collagen and elastin fibers, it contributes to the resistance of a muscle to tensile forces.
List of Clinical Correlates
—Myasthenia gravis
—Mysium damage
—Connective tissue disease
References
Dorland, W. (2011) Dorland's Illustrated Medical Dictionary. 32nd edn. Philadelphia, USA: Elsevier Saunders.
Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41 edn.: Elsevier Limited.
