The biceps brachii is made up of both a long and short head. The function of the muscle is to bring the forearm closer to the upper arm. This can be achieved by either bringing the hand towards the shoulder or by bringing the forearm across the chest towards the opposite shoulder.
The biceps brachii is a muscle that functions to flex the elbow joint. This is achieved by bringing the forearm up towards the upper arm as if to scratch your shoulder. The biceps brachii is innervated by the musculocutaneous nerve. This means that it can be voluntarily controlled or stimulated unless there is a lesion on the musculocutaneous nerve which would require the muscle to be innervated by the radial nerve.
The biceps brachii works with two other muscles to produce flexion of the forearm at the elbow joint. These are the coracobrachialis, which runs from the shoulder blade to three-quarters of the way down through the biceps brachii, and the brachialis, which is located underneath the biceps brachii.
The biceps brachii is made up of two parts –
a long head and a short head. The long head originates on the supraglenoid tubercle of the scapula within the rotator cuff tendons. It inserts onto the radial tuberosity. The short head starts at the coracoid process of the scapula and also ends on the radial tuberosity.
A large tendon from each slips through a common channel, called the intertubercular groove, before inserting onto the lateral supracondylar ridge of the humerus bone.
There are two biceps brachii muscles in the body –
a short head and a long head. They originate on different parts of the scapula, but their insertion is adjacent to each other. The biceps brachii has an important role in stabilizing the arm when throwing a ball, especially when the elbow is fully extended. This can be seen in baseball players when they are at the top of their throwing movement.
An injury to this muscle can occur through overexertion with weights, or it can be caused by a complete disruption/tear of the tendon at its insertion into the radial tuberosity. This is more common in men than women. A rupture in the long head can be caused by suddenly forced abduction of the arm, such as during a fall onto an outstretched hand.
The tendon becomes partially separated from its insertion and when excessive force is placed on the muscle, it tears completely causing intense pain in the shoulder/biceps region. This injury can require surgery to reattach the tendon into its correct position on the bone.
The biceps brachii is a muscle that plays a vital role in the everyday life of humans, but also across all levels of sports and fitness.