15.5: Axial and Appendicular Muscles
Skeletal muscles, the key players in our body's movement, can be classified into two groups based on their location and function: axial muscles and appendicular muscles. These classifications reflect the primary roles the muscles play in the body's structure and movement.
Axial Muscles
Axial muscles, situated along the body's midline, are intricately connected to the axial skeleton, which includes the skull, spine, ribs, and sternum. These muscles facilitate facial expressions and play a crucial role in various head and neck movements, speaking, and eating. They even contribute to controlling the movements of the vertebral column in coordination with the back muscles. Furthermore, the thoracic muscles, including the rectus, oblique, and transverse abdominal muscles, form the anterolateral walls of the trunk, offering stability and support. Additionally, the lower axial skeleton muscles extend between the sacrum and pelvic girdle, actively participating in forming the pelvic floor.
Appendicular Muscles
In contrast, appendicular muscles are predominantly associated with the pectoral girdle, pelvic girdle, and limbs. These muscles provide stability and support and actively contribute to the body's movement during activities like walking, running, and various physical actions. The upper limbs are equipped with muscles that extend from the shoulders down to the hands, enabling us to perform intricate tasks. Similarly, the lower limbs have muscles stretching from the hips to the feet, ensuring mobility and balance.
