Descriptive terms are used to name skeletal muscles PDF

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Descriptive terms are used to name skeletal muscles...

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Descriptive terms are used to name skeletal muscles The human body has approximately 700 muscles. You do not need to learn every one of their names, but you will have to become familiar with many of them. Fortunately, the names anatomists assigned to the muscles include descriptive terms that can help you remember the names and identify the muscles. When you are faced with a new muscle name, it is helpful to first identify the descriptive portions of the name. The name of a muscle may include descriptive information about its region of the body; position, direction, and fascicle arrangement; structural characteristics; and action. Table 11–1 includes a useful summary of muscle terminology. Region of the Body Regional terms are most common as modifiers that help identify individual muscles. In a few cases, a muscle is such a prominent feature of a body region that a name referring to the region alone will identify it. Examples include the temporalis of the head and the brachialis (bra . -ke . -A-lis) of the arm. Position, Direction, or Fascicle Arrangement

Muscles visible at the body surface are often called externus or superficialis. Deeper muscles are termed internus or profundus. Superficial muscles that position or stabilize an organ are called extrinsic. Muscles located entirely within an organ are intrinsic. Muscle names may be directional indicators. For example, transversus and oblique indicate muscles that run across (transversus) or at a slanting (oblique) angle to the longitudinal axis of the body. A muscle name may refer to the orientation of the muscle fascicles within a particular skeletal muscle. Rectus means “straight,” and most rectus muscles have fascicles that run along the longitudinal axis of the muscle. Because we have several rectus muscles, the name typically includes a second term that refers to a precise region of the body. For example, the rectus abdominis of the abdomen is an axial muscle that has straight fascicles that run along its long axis. However, in the case of the rectus femoris, rectus refers to “straight muscle of the thigh” and not to its fascicles (which are bipennate)....