What is the sternal head?
The sternal head is a round fasciculus, tendinous in front, fleshy behind, arising from the upper part of the front of the manubrium sterni. It travels superiorly, laterally, and posteriorly.
What are the two heads of the PEC major?
There are 2 heads of the pectoralis major, the clavicular and the sternocostal, which reference their area of origin[1][2].
What is the action of the pectoralis major muscle?
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 are the 4 pectoral muscles?
The pectoral region is located on the anterior chest wall. It contains four muscles that exert a force on the upper limb: the pectoralis major, pectoralis minor, serratus anterior and subclavius.
Is the pectoralis major a flexor or extensor?
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.
Which of the following is the insertion of the pectoralis major?
Pectoralis major muscle
| Origin | Clavicular part: anterior surface of medial half of clavicle Sternocostal part: anterior surface of sternum, Costal cartilages of ribs 1-6 Abdominal part: Anterior layer of rectus sheath |
|---|---|
| Insertion | Crest of greater tubercle of humerus |
What is the proximal attachment of the pectoralis major?
| Pectoralis major | |
|---|---|
| Insertion | Lateral lip of the bicipital groove of the humerus (anteromedial proximal humerus) |
| Artery | pectoral branch of the thoracoacromial trunk |
| Nerve | lateral pectoral nerve and medial pectoral nerve Clavicular head: C5 and C6 Sternocostal head: C7, C8 and T1 |
Where is the insertion of the PEC major?
tubercle of humerus
Pectoralis major muscle
| Origin | Clavicular part: anterior surface of medial half of clavicle Sternocostal part: anterior surface of sternum, Costal cartilages of ribs 1-6 Abdominal part: Anterior layer of rectus sheath |
|---|---|
| Insertion | Crest of greater tubercle of humerus |
Where is the clavicular head?
The clavicular head of the sternocleidomastoid muscle is the more lateral and posterior of the two heads of origin of the sternocleidomastoid muscle. It connects the skull to the clavicle and allows the head to flex or rotate. The sternocleidomastoid is clinically significant as an anatomical landmark.
Where is the sternal region?
The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury.
Is the pectoralis major anterior or posterior?
The pectoralis major is thick and fan-shaped, covering much of the superior portion of the anterior thorax.
Where does the pectoralis major insert quizlet?
Origin: Ribs 3-5 near costal cartilages, Inserts medial border and superior surface of coracoid process of scapula, innervation Medial Pectoral nerve, Fx, Stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall.