Muscles of the shoulder region, and axilla Flashcards
What are the primary muscles of the shoulder region?
- Trapezius
- Levator scapulae
- Pectoralis minor
- Rhomboid major
- Rhomboid minor
- Serratus anterior
- Pectoralis major
- Latissimus dorsi
- Rotator cuff muscles (Supraspinatus, Infraspinatus, Teres minor, Subscapularis, Teres major, Deltoid)
What is the function of the trapezius muscle?
- Elevate the shoulder girdle (upper fibres)
- Retract the shoulder girdle (middle fibres)
- Depress the shoulder girdle (lower fibres)
- Rotate the scapula during abduction
- Fixate the shoulder girdle
What are the functions of the levator scapulae muscle?
Elevation of shoulder girdle
What is the role of the serratus anterior muscle?
- Protraction of scapula
- Rotation of scapula during abduction
- Keeps the costal surface of the scapula closely opposed to the thoracic wall
List the rotator cuff muscles.
- Subscapularis
- Supraspinatus
- Infraspinatus
- Teres minor
What is the primary function of the supraspinatus muscle?
Abductor of the shoulder joint
What is the primary function of the infraspinatus muscle?
Lateral rotator of the shoulder joint
What are the functions of the deltoid muscle?
- Abduction (middle fibres)
- Flexion (clavicular fibres)
- Extension (posterior fibres)
What is the function of the teres major muscle?
- Medially rotates the arm
- Extends the arm
What are bursae and their role in the shoulder region?
Bursae connect with the synovial cavity and facilitate movement of tendons over joints
What are the contents of the axilla?
- Axillary artery and branches
- Axillary veins and tributaries
- Brachial plexus
- Axillary lymph nodes
What is the anatomical significance of the axilla?
It connects structures from the base of the neck to the upper limb
What are the four walls of the axilla?
- Anterior wall
- Posterior wall
- Lateral wall
- Medial wall
What forms the anterior wall of the axilla?
- Pectoralis major & minor
- Clavipectoral fascia
- Subscapularis
What are the roots of the brachial plexus?
- C5
- C6
- C7
- C8
- T1
What is the function of the pectoralis major muscle?
- Flexes the extended humerus (clavicular head)
- Extends the flexed arm (sternocostal head)
- Adduction and medial rotation (both heads)
What are the functions of the latissimus dorsi muscle?
- Adduction
- Medial rotation
- Extension of the arm
Fill in the blank: The rotator cuff muscles are also known as the _____ muscle group.
SITS
True or False: The axillary artery is located at the apex of the axilla.
True
What is the role of the axillary lymph nodes?
Involved in lymphatic drainage and immune response
What is the function of the rhomboid major and minor muscles?
Retraction of the shoulder girdle
What is the significance of the axillary artery?
It supplies blood to the upper limb
What are the main actions of the muscles moving the shoulder joint?
- Flexion
- Extension
- Abduction
- Adduction
- Medial rotation
- Lateral rotation
Fill in the blank: The _____ bursa facilitates movement of the supraspinatus tendon under the coracoacromial arch.
Subacromial
