The Pectoral Girdle Flashcards
Joints of the pectoral girdle
Sternoclavicular, acromioclavicular, joint capsule, and the scapula thoracic.
Anterior muscles of the pectoral girdle
Movements of pelvic girdle
Subclavius: steadies the clavicle in the sternoclavicular joint
pectoralis major: protraction
serratus anterior: protraction, lateral rotation.
-Lie on the anterior and lateral thoracic wall
Posterior muscles of the pelvic girdle
Movements of pelvic girdle
Trapezius- elevation, depression, retraction, lateral rotation
levator scap: elevation, medial rotation.
Rhomboids: retraction, medial rotation.
-superficial muscular layer of the back
subclavius muscle origin
1st rib
subclavius insertion
Clavicle (inferior surface)
Subclavius innervation
N. To Subclavius (C5-6)
subclavius action
Steadies the clavicle to sternoclavicular joint
Pectoralis Minor origin
3-5th ribs
Pectoralis Minor insertion
Coracoid process
Pectoralis Minor action
Draws scapula downward (causing inferior angle to move posteromedially), rotates glenioid inferiorly, assists respiration
serratus anterior origin
1st-9th ribs
serratus anterior insertion
Scapula (medial border)
serratus anterior innervation
Long thoracic nerve (C5-7)
serratus anterior action
Superior: lowers raised arm (arm adduction)
Inferior: rotates scapula laterally
Entire muscle: draws scapula laterally forward, elevates ribs when shoulder is fixed
What composes the pectoral girdle?
Clavicle and the scapula.
Function: attaches upper limb to the trunk and allows range of motion for upper limb function
Trapezius origin
Descending: C1-7 and occipital bone.
Transverse: aponeurosis T1-4 spinous processes.
Ascending: T5-T12 spinous processes
Trapezius insertion
Descending: Lateral 3rd of the clavicle
Transverse: acromion
Ascending: Scapula spine
Trapezius innervation
Accessory nerve (CN XI) C3-4 of cervical plexus
Action of trapezius
Draws scapula medially, downward, upward, rotates glenoid cavity superiorily, tilts head to sane side and rotates it to the opposite.
Levator scapula
OINVA
C
Rhomboids
Last exam
Pectoralis minor innervation
Medial pectoral nerve (C8,T1)
