Podcast
Questions and Answers
What is the inferior boundary of the pectoral region?
What is the inferior boundary of the pectoral region?
Which muscle is considered part of the superficial layer of the pectoral region?
Which muscle is considered part of the superficial layer of the pectoral region?
Which vertical line passes through the middle of the clavicle?
Which vertical line passes through the middle of the clavicle?
What is the primary action of the pectoralis major?
What is the primary action of the pectoralis major?
Signup and view all the answers
Which of the following structures is NOT a part of the fascia in the pectoral region?
Which of the following structures is NOT a part of the fascia in the pectoral region?
Signup and view all the answers
The nerve supply for pectoralis major comes from which nerves?
The nerve supply for pectoralis major comes from which nerves?
Signup and view all the answers
Which line runs through the anterior axillary fold?
Which line runs through the anterior axillary fold?
Signup and view all the answers
What action does the pectoralis minor muscle primarily perform?
What action does the pectoralis minor muscle primarily perform?
Signup and view all the answers
What is the primary action of the subclavius muscle?
What is the primary action of the subclavius muscle?
Signup and view all the answers
Which structures pierce the clavipectoral fascia?
Which structures pierce the clavipectoral fascia?
Signup and view all the answers
Where does the pectoralis minor attach on the scapula?
Where does the pectoralis minor attach on the scapula?
Signup and view all the answers
What is the innervation of the pectoralis major muscle?
What is the innervation of the pectoralis major muscle?
Signup and view all the answers
What ligament is formed from the thickened upper border of the clavipectoral fascia?
What ligament is formed from the thickened upper border of the clavipectoral fascia?
Signup and view all the answers
Which movement is specifically associated with the clavicular head of the pectoralis major?
Which movement is specifically associated with the clavicular head of the pectoralis major?
Signup and view all the answers
Which fascia encloses the mammary glands and cutaneous nerves?
Which fascia encloses the mammary glands and cutaneous nerves?
Signup and view all the answers
What does the clavipectoral fascia split to enclose?
What does the clavipectoral fascia split to enclose?
Signup and view all the answers
Study Notes
Pectoral Region
- The pectoral region encompasses structures on the front of the upper chest (anterior thoracic wall).
- Boundaries:
- Above: Clavicle
- Below: 6th rib
- Medially: Midline
- Laterally: Mid-axillary line
Objectives
- Definition of the pectoral region
- Identifying the boundaries of the pectoral region
- Determining the layers within the pectoral region
- Listing the muscles composing the pectoral region
- Describing the fasciae of the pectoral region
Layers of the Pectoral Region
- Skin
- Superficial fascia
- Deep fascia (pectoral fascia)
- Clavipectoral fascia
Muscles of the Pectoral Region
- Pectoralis major
- Origin: Clavicular head (medial half of clavicle); sternocostal head (anterior surface of sternum, first seven costal cartilages, aponeurosis of external oblique)
- Insertion: Lateral lip of the intertubercular sulcus (bicipital groove) of the humerus
- Nerve supply: Medial and Lateral pectoral nerves
- Action: Adduction, flexion, and medial rotation of the arm; accessory muscle of inspiration
- Pectoralis minor
- Origin: Anterior surfaces and superior borders of ribs 3-5
- Insertion: Coracoid process of scapula
- Nerve supply: Medial pectoral nerve
- Action: Protraction of scapula, depression of shoulder, accessory muscle of inspiration
- Subclavius
- Origin: First rib at the costochondral junction
- Insertion: Groove on the inferior surface of the middle one-third of the clavicle (subclavius groove)
- Nerve supply: Nerve to subclavius
- Action: Stabilizes the clavicle during shoulder girdle movements; protects vessels and nerves from the bone
Fasciae of Pectoral Region
- Superficial fascia: Encloses mammary glands, platysma, and cutaneous nerves.
- Deep fascia: (pectoral fascia)
- Clavipectoral fascia: A strong fibrous sheet deep to the clavicular head of pectoralis major. Extends from pectoralis minor to clavicle, and thickens at the first rib forming the costocoracoid ligament. Attaches to the clavicle and joins the floor of axilla.
Structures Piercing Clavi-Pectoral Fascia
- Vein: Cephalic vein (terminates in axillary vein)
- Artery: Acromiothoracic artery (branch from axillary artery)
- Nerve: Lateral pectoral nerve (branch from lateral cord of brachial plexus)
- Lymphatic vessels: Enter infra-clavicular lymph nodes
Nerve Supply for Pectoralis major
- Medial and lateral pectoral nerves
Clavicular Head of Pectoralis Major
- Specifically responsible for the movement of shoulder flexion.
Pectoralis Minor Attachment on Scapula
- Coracoid process
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the pectoral region's anatomy, including its boundaries, layers, and muscles. You will learn to identify the components such as the fasciae and the pectoralis major muscle. Understanding this region is crucial for anatomy and medical studies.
