Lecture 10 - The Shoulder Girdle Flashcards
Pectoralis major
innervation and action
Innervation: Lateral/medial pectoral nerves
Action: Adducts, medial rotation, flex humerus, scapula protraction
Pectoralis minor
innervation and action
Innervation: Medial pectoral nerve
Action: Stabilizes scapula against thoracic wall (anterior/inferior)
Subclavius
innervation and action
Innervation: subclavian nerve
Action: depresses scapula
Serratus anterior
innervation and action
Innervation: Long thoracic nerve
Action: Protraction, upward rotation of the scapula
Deltoid
innervation and action
Innervation: axillary nerve
Action:
-Abduct the arm after the first 15°
-Flex and medially rotate the arm (clavicular portion)
-Extend and laterally rotate the arm (spinous portion)
Subscapularis
innervation and action
Innervation: upper and lower subscapular nerves
Action: Medially rotates the humerus and helps stabilize its head in the glenoid cavity
Supraspinatus
innervation and action
Innervation: Suprascapular nerve
Action: Initiates first 15° of abduction
Infraspinatus
innervation and action
Innervation: Suprascapular nerve
Action: Lateral rotation at GH joint
Teres minor
innervation and action
Innervation: Axillary nerve
Action: Lateral rotation at GH joint
Teres major
innervation and action
Innervation: Lower subscapular nerve
Action: Adduction, extension, & Medial rotation at GH joint
Long head of triceps brachii
innervation and action
Innervation: Radial nerve
4 rotator cuff muscles
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
Structures at risk from impingement syndrome
Supraspinatus
Subacromial bursa
Tendon of long head of bicep
“Frozen Shoulder” is the result of inflammation, scarring, thickening, and shrinkage of the capsule that surrounds the joint. This is also known as
Adhesive Capsulitis of the Glenohumeral Joint
