Axial and Appendicular Muscles

Axial versus Appendicular Muscles

Axial muscles are a part of the central body, the head, neck, and trunk. Appendicular muscles are those attached to the upper and lower limbs, hands, and feet

There are three types of muscle in the human body, skeletal (also called striated or voluntary), cardiac, and smooth (also called unstriated or involuntary). The skeletal muscles are named based on their attachment to the skeleton and fascia of the limbs, body wall, and head/neck. Skeletal muscles are divided into axial and appendicular categories. Axial muscles (the word axial in anatomy pertains to the central part of the body, distinct from the limbs) include those of the trunk and head. Appendicular muscles (the word appendicular in anatomy means relating to the limbs) are those attached to the arms, legs, hands, and feet.

The axial muscles of the head include those which control facial expression and eye movements, in addition to those responsible for the chewing and swallowing of food. Neck muscles allow for flexion and extension of the neck. Trunk muscles provide stability to the vertebral column, aid in respiration, and assist in flexion and rotation of the spine. Pelvic floor muscles are also considered a part of the axial musculature. In men and women, they aid in urination, defecation, and sexual function.

Appendicular muscles encompass those of the shoulders, upper limbs, and hands. These muscles permit a variety of movements including, but not limited, to raising and lowering of the arms, punching, pulling, and lifting. Delicate muscles of the hands are responsible for fine motor activities like those involved in writing, typing, piano-playing, and fine pincer grasp. Muscles of the hips and legs offer stability to the body, in addition to activities such as walking, running, jumping, and the maintenance of balance. Muscles of the feet aid in locomotion by permitting flexion, extension, abduction, and adduction of the foot.