What is the innervation of pectoralis major?
The pectoralis major muscle is innervated by the lateral and medial pectoral nerves (root value C5-T1), which stem from the brachial plexus.
What Innervates the sternocostal head of the pectoralis major?
The medial pectoral nerve
The medial pectoral nerve innervates the sternocostal head. The lateral pectoral nerve arises directly from the lateral cord of the brachial plexus, and the medial pectoral nerve arises from the medial cord. [1][2] The lateral cord will travel anteriorly to the axillary artery and medial cord to the pectoralis minor.
What is the innervation to pectoralis major and minor?
Innervation to the pectoralis minor is also received from the lateral pectoral nerve, via a communicating branch known as the ‘ansa pectoralis’, which is usually found anterior to the first part of the axillary artery. That results in the pectoralis minor receiving innervation from the spinal roots of C5-T1.
Does the pectoralis major act on the arm?
Actions of Pectoralis Major Muscle: Flex the arm at the shoulder (glenohumeral) joint. Extends the arm at the shoulder (glenohumeral) joint from a flexed position.
What supplies pec minor and major?
thoracoacromial artery
The blood vessel that supplies the pectoralis minor muscle is the thoracoacromial artery; a short artery that branches off from the larger axillary artery of the chest and upper extremities.
What nerve pierces the pectoralis minor?
medial pectoral nerve
The medial pectoral nerve pierces both the pectoralis minor and the sternocostal head of the pectoralis major. The lateral pectoral nerve pierces only the clavicular head of the pectoralis major.
What is the antagonist of the pectoralis major?
Deltoid muscle
| Pectoralis major | |
|---|---|
| Antagonist | Deltoid muscle, Trapezius |
| Identifiers | |
| Latin | Musculus pectoralis major |
| TA98 | A04.4.01.002 |
Where does the pectoral nerve originate?
the brachial plexus
Origin and course The medial pectoral nerve (C8, T1) arises as the lateral branch of the medial cord of the brachial plexus. It originates posterior to the axillary artery. Upon originating, the nerve runs anteriorly towards the pectoral muscles alongside the axillary vein and axillary artery.
What actions does the pectoralis major do?
The pectoralis major extends across the upper part of the chest and is attached to a ridge at the rear of the humerus (the bone of the upper arm). Its major actions are adduction, or depression, of the arm (in opposition to the action of the deltoideus muscle) and rotation of the arm forward about the axis of the body.
What Innervates serratus anterior?
Innervation. The innervation is supplied by the long thoracic nerve (C5-7), a branch of the brachial plexus.
What nerve Innervates the pectoral muscles?
lateral pectoral nerve
The lateral pectoral nerve mostly carries motor fibers. Its main function is to provide motor innervation primarily to the pectoralis major muscle, but also provides minor contributions to the pectoralis minor muscle.
What nerve pierces pec major?
The medial pectoral nerve pierces both the pectoralis minor and the sternocostal head of the pectoralis major. The lateral pectoral nerve pierces only the clavicular head of the pectoralis major.
What is the synergist of pectoralis major?
Agonist: Pectoralis Major. Synergist: Triceps & Serratus Anterior.
What nerve innervates the pectoralis minor?
The medial pectoral nerve enters the pectoralis minor muscle in which it gives off several branches that supply the muscle. The nerve then perforates the pectoralis minor muscle to reach the pectoralis major muscle. The pectoralis major muscle consists of a clavicular part and a sternal part.
What Innervates the medial pectoral nerve?
Pectoralis majorMedial pectoral nerve / InnervateThe pectoralis major is a thick, fan-shaped or triangular convergent muscle, situated at the chest of the human body. It makes up the bulk of the chest muscles and lies under the breast. Beneath the pectoralis major is the pectoralis minor, a thin, triangular muscle. Wikipedia
How does pectoralis major Extend arm?