What is the pectoralis major

The pectoralis major is a paired, superficial muscle located on the anterior surface of the thoracic cage. … The pectoralis major has a broad origin, based on which it is divided into three parts: clavicular part, sternocostal part and abdominal part.

What is pectoralis major muscle?

The pectoralis major muscle is a large muscle in the upper chest, fanning across the chest from the shoulder to the breastbone. The two pectoralis major muscles, commonly referred to as the ‘pecs,’ are the muscles that create the bulk of the chest.

What Innervates pectoralis major?

The fourth intercostal nerve participated in the inferolateral muscle supply (4/30). Conclusions: The muscle is mainly innervated by the lateral pectoral nerve supplemented by the branches of the MPN.

What is pectoralis major and its function?

The pectoralis major’s primary functions are flexion, adduction, and internal rotation of the humerus. The pectoral major may colloquially be referred to as “pecs”, “pectoral muscle” or “chest muscle” due to it being the largest and most superficial muscle in the chest area.

What are the actions of pectoralis major?

The main function of this chest muscle as a whole is the adduction and internal rotation of the arm on the shoulder joint. Acting independently, the clavicular part helps to flex the extended arm up to 90°, while the sternocostal part facilitates the extension of the flexed arm by pulling it downwards.

What is the action of the pectoralis major muscle quizlet?

Origin: Clavicular head: Anterior surface of the medial half of the clavicle, Sternocostal head: Anterior surface of sternum superior 6 costals, and aponeurosis of external oblique, INsert: Lateral lip of intertubercular groove of humerus, Innervation: Lateral and medial pectoral nerves (C5-T1), Fx: Adducts and …

What does the pectoralis major muscle do quizlet?

What does the pectoralis major muscle do? It adducts the arm.

Where is the pectoralis major located?

The pectoralis major is the superior most and largest muscle of the anterior chest wall. It is a thick, fan-shaped muscle that lies underneath the breast tissue and forms the anterior wall of the axilla.

What is the function of the pectoralis minor muscle?

Function. The primary actions of this muscle include the stabilization, depression, abduction or protraction, internal rotation and downward rotation of the scapula. It elevates the ribs for deep inspiration when the pectoral girdle is fixed or elevated.

How did the pectoralis major get its name?

The name pectoralis major describes the general location of this muscle. Pectoralis comes from the Latin word “pectus” meaning breast and major comes from Latin and means “greater than”.

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Where does pectoralis major attach?

Anatomy. The pectoralis major muscle inserts superiorly into the inferior clavicle, supero-laterally into the proximal humerus, and medially into the sternum. It extends down to the seventh rib.

How do you palpate the pectoralis major?

For palpation of the pectoralis major muscle, the musculature is accessible with the hand, between the axilla and the nipple. For a palpatory clinical visit, the pectoralis minor muscle can be palpated by placing a finger in the axilla and pushing obliquely towards the coracoid process of the scapula.

Why does my pectoralis major hurt?

The pectoralis major tendon is most commonly injured during an eccentric contraction – when the external force on the muscle is greater than the force that the muscle can generate – and when the arm is extended and externally (outwardly) rotated, such as when performing a bench press.

How do I activate my pectoralis major?

1. Pushups. Pushups are the most obvious choice because they require no special equipment and can be done anywhere. …
2. Dumbbell press. Somewhat like a bench press the dumbbell press is another good choice for building pectoral muscles. …
3. Bench press.

What is the origin of the pectoralis major muscle quizlet?

The origin of the pectoralis major muscle is the coracoid process of the scapula. The insertion of the coracobrachialis muscle is on the coracoid process of the scapula. … The clavicular head of the pectoralis major muscle is innervated by the lateral pectoral nerve arising from C5, C6, and C7.

What do sphincters help to regulate?

Sphincters are special, circular muscles that open and close certain body parts. Most often, the action of a sphincter is to regulate the passage of some type of fluid, such as bile, urine, or fecal matter.

Which of the following is the origin insertion action or innervation of the pectoralis major quizlet?

Which of the following is the origin, insertion, action, or innervation of the pectoralis major? It is innervated by the medial and lateral pectoral nerves.

Which of the following is the insertion of the pectoralis minor quizlet?

The insertion of the pectoralis minor is the coranoid process of the scapula. The origin of the subclavius is the superior aspect of the first rib at its junction with its costal cartilage.

Where does the deltoid originate?

OriginsLateral 1/3 of Clavicle (clavicular part), Acromion (acromial part), Spine of Scapula (spinal part) Mnemonic: ‘Deltoid helps you carry SACS’InsertionDeltoid tuberosity of humerusInnervationAxillary nerve (C5, C6)

What is the action of the latissimus dorsi muscle quizlet?

Palpation: Latissimus dorsi and theres major both compromise the posterior portion of the axilla and can be palpated together at the posterior axillary fold. Action: Lateral Rotation, aDDuction and Extension of the arm.

What does pectoralis major pain feel like?

What are the symptoms of a pectoralis major strain? The first sensation felt when the pectoralis major muscle is torn is sudden pain. This pain is usually felt at the front of the armpit and is sometimes felt across the chest. At the same time you may also feel something ‘tearing’ in your chest.

What muscles extend the forearm?

The triceps brachii extend the forearm.

What is muscle under armpit called?

Pectoralis major: This large fan-shaped muscle stretches from the armpit up to the collarbone and down across the lower chest region. It connects to the sternum (breastbone). Pectoralis minor: The smaller of the pectoralis muscles, this muscle fans out from the upper ribs up to the shoulder area.

Where is the biceps?

The biceps muscle is located at the front of your upper arm. The muscle has two tendons that attach it to the bones of the scapula bone of the shoulder and one tendon that attaches to the radius bone at the elbow. The tendons are tough strips of tissue that connect muscles to bones and allow us to move our limbs.

What muscle is under your breast?

The pectoral muscle passes underneath the breast and connects the chest and the arm. Lying further below the pectoral muscle are the ribs which are connected by intercostal muscles, which raise and lower the rib cage when breathing in and out.

What are the 4 pectoral muscles?

• pectoralis major.
• pectoralis minor.
• subclavius.
• serratus anterior.

Where does pectoralis minor attach?

OriginAnterior surface, costal cartilages of ribs 3-5InsertionMedial border and coracoid process of scapulaInnervationMedial and lateral pectoral nerves (C5-T1)Blood supplyThoracoacromial a. (pectoral and deltoid branches), superior thoracic a., lateral thoracic a.

What sports use the pectoralis major?

Football, baseball, swimming and rowing are sports in which your chest strength and endurance is repeatedly put to the test.

How do you relieve pectoralis major pain?

1. Rest. Stop activity as soon as you notice pain. …
2. Ice. Apply ice or a cold pack to the affected area for 20 minutes up to three times a day.
3. Compression. Consider wrapping any areas of inflammation with an elastic bandage but don’t wrap too tightly as it may impair circulation.
4. Elevation.

Can a woman pull a chest muscle?

The terms pulled muscle and muscle strain refer to an injury that involves an overstretched or torn muscle. A person with a muscle strain in the chest may experience sudden, sharp pain in this area. Although uncomfortable, a strained chest muscle is usually a minor injury that tends to heal within days or weeks.

How do you heal pectoralis major?

1. muscle tear – Relative rest, Ice, Compression and Elevation (helps reduce the inflammation to the injured tissue allowing for a quicker recovery time).
2. Effleurage massage can help reduce swelling to the area.