Latissimus Dorsi and its Functions

Latissimus Dorsi is basically the largest and widest muscle present in the back of human body. The origin of lattissimus dorsi: Spinous processes of vertebrae T7-L5 Though it is the widest muscle but it is quiet thin and is triangularly shaped at the back. The word latissimus dorsi has been originated from the Latin word “latissimus” means broadest and dorsum means back which means “broadest of the back”. It plays a synergistic role in lateral flexion and extension of lumbar spine it also helps in internal rotation of the shoulder joint. It is also called as “lat”. Trapezius is another muscle covers some part of lattisimus dorsi which is also the largest muscle in the upper and middle back. The structure of lattissimus dorsi is divided into three parts variation, traingles and nerve supply.
The total number of dorsal vertebrae to which lats are attached can be from four to eight, the total number of costal attachments varies; the muscle fibers may or may not reach the crest of the illium. The axillary arch is a muscular slip which varies from 5 to 15 mm in breadth and 7 to 10 cm in length. Sometimes the springs from the upper edge of the lattissimus dorsi about the middle of the posterior fold of the axilla in front of the axillary vessels and nerve to the under surface of the tendon of the coracobrachialis, pectoralis major or the fascia over the bicep brachii. The axiilray artery is crossed by axillary arch, just above the spot generally selected for the application of a ligature and may mislead a surgeon. The interior angle of the scapula is crossed by lattissimus dorsi.

The various function of lattisimus dorsi

The key function lattissimus dorsi is to contribute to brachial and thoracic that is arm motion. Lattissimus dorsi is quiet responsible for adduction, extension and transverse extension which is also called as horizontal abduction. It is also responsible, for internal rotation of the shoulder joint. Lattissimus dorsi also provides a synergetic role for extension of posterior fibers and lateral fibers of the lumbar spine. As a muscle it assists both accessory muscle of inspiration and forced expiration that is anterior fibers. Most of the lattissimus dorsi work outs simultaneously recruit posterior fibers of the deltoid, teres major, long head of triceps branchii which is among other numerous stabilizing muscles. The compound exercises for lattissimus dorsi mostly involves elbow flexion and they tend to recruit brachalis, biceps brachii and brachioradials for this particular function. According to the line of pull, the trapezius muscles can be involved as well. In horizontal pulling motion such as the rows involves trapezius and latissimus dorsi heavily.
In order to understand better what basically it does is to pull the arm back, down and it keeps the elbow close to the body. If a person is stretching, without actually bending that person would be able to pull arm down about 2 inches. For strength, power and size