Muscles Of The Shoulder Girdle Flashcards
The only bony articulation between the upper limb and axial skeleton?
Sternoclavicular joint
Bones of the shoulder girdle
1) Scapula
2) Clavicle
Anatomical joints of the shoulder girdle
1) Glenohumeral joint
2) Sternoclavicular joint
3) Acromioclavicular joint
Physiological joints of the shoulder girdle
Scapulothoracic joint
What joint in the upper limb is supported by muscles
Scapulothoracic joint
Which of these is not an extrinsic muscle:
a) Serratus anterior
b) Teres minor
c) Levator scapulae
d) Pectoralis minor
Teres minor
Extrinsic muscle
Suspends scapula from the trunk. Stabilizes and/or actively moves the scapula
Examples of extrinsic muscle
Serratus anterior
Levator scapulae
Trapezius
Pectoralis minor
Rhomboid major
Rhomboid minor
Intrinsic muscles
Attach the scapula to the humerus
Examples of intrinsic muscles
Deltoid
Teres major
Rotator cuff muscles (supraspinatus, infraspinatus, teres minor, subscapularis).
Muscles that attach trunk to the humerus
Latissimus dorsi
Pectoralis major
Anterior axioappendicular muscles
Serratus anterior
Pectoralis minor
Pectoralis major
Subclavius
Posterior axioappendicular muscles
Trapezius
Latissimus dorsi
Rhomboid minor
Rhomboid major
Levator scapulae
Deltoid
Teres major
Rotator cuff muscles
Trapezius:
Origin
Insertion
Innervation
a) Medial third of the nuchal line, external occipital protuberance, ligamentum nuchae, spinous process of C7-T12
b) Superior fiber - Lateral third of clavicle
Middle fiber - acromion process of scapula
Inferior fiber - Spine of scapula
c) Accessory nerve (CN XI) (motor fibers) & C3, C4 spinal nerve (pain & proprioceptive fibers)
Action of trapezius
Superior fiber - Elevates scapula
Middle fiber - Retracts scapula
Inferior fiber - Depresses scapula
(Superior & inferior fibers act together to rotate glenoid cavity superiorly).
Strap-like muscle in the upper limb?
Levator scapulae
Levator scapulae:
Origin
Insertion
Innervation
a) Posterior tubercules of transverse process of C1-C4
b) Medial border of scapula superior to the root of the spine of the scapula
c) Dorsal scapula (C5), cervical nerves (C3 & C4)