Epimysium (
plural
The plural (sometimes abbreviated pl., pl, or ), in many languages, is one of the values of the grammatical category of number. The plural of a noun typically denotes a quantity greater than the default quantity represented by that noun. This de ...
''epimysia'') (Greek ''epi-'' for on, upon, or above + Greek ''mys'' for muscle) is the fibrous tissue envelope that surrounds
skeletal muscle
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...
.
It is a layer of
dense irregular connective tissue
Dense irregular connective tissue has fibers that are not arranged in parallel bundles as in dense regular connective tissue.
Dense irregular connective tissue consists of mostly collagen fibers. It has less ground substance than loose connecti ...
which ensheaths the entire
muscle
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...
and protects muscles from friction against other muscles and bones.
It is continuous with
fascia
A fascia (; plural fasciae or fascias; adjective fascial; from Latin: "band") is a band or sheet of connective tissue, primarily collagen, beneath the skin that attaches to, stabilizes, encloses, and separates muscles and other internal organs. ...
and other connective tissue wrappings of muscle including the
endomysium
The endomysium, meaning ''within the muscle'', is a wispy layer of areolar connective tissue that ensheaths each individual Skeletal muscle#Skeletal muscle fibers, muscle fiber, or muscle cell. It also contains capillaries and nerves. It overlies ...
and
perimysium
Perimysium is a sheath of connective tissue that groups muscle fibers into bundles (anywhere between 10 and 100 or more) or fascicles.
Studies of muscle physiology suggest that the perimysium plays a role in transmitting lateral contractile ...
. It is also continuous with tendons, where it becomes thicker and
collagenous
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole ...
.
While the epimysium is irregular on muscles, it is regular on tendons.
See also
*
Endomysium
The endomysium, meaning ''within the muscle'', is a wispy layer of areolar connective tissue that ensheaths each individual Skeletal muscle#Skeletal muscle fibers, muscle fiber, or muscle cell. It also contains capillaries and nerves. It overlies ...
*
Perimysium
Perimysium is a sheath of connective tissue that groups muscle fibers into bundles (anywhere between 10 and 100 or more) or fascicles.
Studies of muscle physiology suggest that the perimysium plays a role in transmitting lateral contractile ...
References
Soft tissue
Muscular system
{{muscle-stub