The muscles of the back can be arranged into 3 categories based on their location: superficial back muscles, intermediate back muscles and intrinsic back muscles. The intrinsic muscles are named as such because their embryological development begins in the back, oppose to the superficial and intermediate back muscles which develop elsewhere and are therefore classed as extrinsic muscles.
The superficial back muscles are the muscles found just under the skin. Within this group of back muscles you will find the latissimus dorsi, the trapezius, levator scapulae and the rhomboids.
These muscles are able to move the upper limb as they originate at the vertebral column and insert onto either the clavicle, scapula or humerus.
Whilst the superficial muscles of the back allow movements at the shoulder, the intermediate muscles of the back work to elevate and depress the rib cage. There are two major muscles within this category – the serratus posterior superior and the serratus posterior inferior.
The intrinsic (deep) muscles of the backcan be further subdivided into their own superficial, intermediate and deep layers. These muscles collectively work to help movements of the vertebral column and to also control posture.
In this section, learn more about the muscles of the back– including the superficial, intermediate and intrinsic back muscles.