Skeletal Muscle Anatomy

Skeletal muscle three features

nerve and blood supply, connective tissue sheaths, and attachments

Nerve and blood supply

Muscles contain nerves, arteries, and veins. Nerves allow for control. Contracting fibers require oxygen, nutrients, and waste removal.

Connective tissue sheaths

Support cells and reinforce whole muscle

Epimysium sheaths

dense irregular connective tissue surrounding entire muscle

Perimysium sheaths

fibrous connective tissue surrounding fascicles

Endomysium sheaths

fine areolar connective tissue surrounding each muscle fiber

muscle attachments

Muscles cross joints and attach to bones

insertion

attachment to movable bone

Origin

attachment to immovable or less movable bone

Direct (fleshy) attachment

The epimysium is continuous with periosteum

Indirect attachment

epimysium continues as tendon or aponeurosis that merges into periosteum as perforating fibers