Dorothy FarrarMusculus biceps brachii (Bizeps)
The two-headed upper arm muscle is called the biceps brachii muscle . The muscle is popularly known as the biceps .
Definition
Musculus biceps brachii is the name for the biceps muscle. It is located on the front of the upper arm and is part of the flexor muscles of the upper arm. The two-jointed muscle extends over the elbow joint (articulatio cubiti) and the shoulder joint (articulatio humeri). The Latin translation of Musculus biceps brachii means “arm flexor” or “two-headed arm muscle”.
The biceps brachii muscle is also found in quadruped mammals such as dogs. There he takes care of the bending of the front leg. The term biceps also carries the thigh flexor muscle (musculus biceps femoris). In the case of the upper arm muscle, however, this name is used much more frequently.
Anatomy
The biceps muscle is a skeletal muscle located on the front or upper side of the upper arm. It is used to bend the arm. The biceps brachii muscle is composed of two muscle heads that originate in the shoulder blade .
The names of the two muscle heads are caput breve (short head) and caput longum (long head). The muscle heads have a significant part in the naming of the biceps. At the point where they can be seen from the outside, the caput breve and caput longum join. There they join together to form a single muscle belly.
This muscle body is located below the crook of the elbow at the muscle tubercle. There is also a tendon of the upper arm that extends like a branch in the direction of the aponeurosis musculi bicipitis, the tendon origin of the muscle. In addition, there is a transition to the facia antebrachii, which is a forearm fascia . The musculocutaneous nerve, which emerges from the brachial plexus, is responsible for the blood supply to the biceps.
In contrast to humans, there is only one origin of the biceps muscle in quadrupeds such as cats, dogs or horses at the tuberculum supraglenoidale (bone hump). As a result, the biceps brachii muscle only has a single head. Anatomically, however, doctors refer to it as the two-headed biceps muscle.
function
The most important function of the biceps brachii muscle is rotating the forearm from its basic position. The thumb moves from the inside to the outside position. Finally, it points vertically in the upper direction as well as in the other basic direction. This process is also known as supination. If the forearm has already assumed a supinated position, the biceps muscle can return it to its previous position.
Furthermore, the biceps brachii muscle performs flexion movements in the elbow region. Both the long head and the short head perform independent tasks that affect the biceps muscle. When the upper arm moves away from the chest , the caput breve is stressed. This also takes care of movements that point the arm towards the chest.
When the arm extends forward and away from the body, both heads are involved in this process. They also work together in the internal rotation of the arm, resulting in smooth movements. This prevents the arm from rotating too far, which in turn counteracts injuries.
Unlike humans, the biceps brachii muscle in animals does not rotate. So it only serves to bend the elbow. As a result, the development of the biceps muscle is weaker than in humans.
diseases
- biceps tendon rupture
- pulley lesion
The biceps muscle is prone to various injuries. It is most commonly affected by a ruptured biceps tendon. This is a rupture of the long biceps tendon. A biceps tendon rupture is triggered by permanent damage to the shoulder joint , which is associated with instability of the upper arm groove.
These problems create inflammation that can lead to complete rupture of the tendon. Seniors are particularly affected by this injury, as they are subject to increased wear and tear due to their age. The biceps brachii muscle becomes more susceptible to injury over the years.
On the other hand, a rupture of the short biceps tendon is relatively rare. This can lead to a rupture of the biceps tendon insertion at the level of the elbow. In contrast to tears in the long biceps tendon, which can be functionally tolerated, a tear in the short biceps tendon always results in extensive functional deficits. For this reason, a surgical intervention must always be carried out.
Disorders of the biceps muscle include the pulley lesion. This is a displacement of the original tendon. The tendon gradually slips into the shoulder joint groove. Possible reasons for this are accidents or overloading.
Dislocations of the biceps brachii muscle occur very rarely before birth. As the tendon shifts, it becomes progressively thinner as it progresses, leading to an increased susceptibility to injury.
Hello and welcome to my Health Guide & Encyclopedia! My name is Dorothy Farrar, and I'm the founder and main author of this platform.
My passion for health and wellness started at a young age when I became interested in the connection between the food we eat and the way we feel. This fascination led me to study nutrition and dietetics in college, where I learned about the importance of a balanced diet and the impact of various nutrients on the body.