Muscle Chart: Pectoral Girdle And Axilla

Question 1

Subclavius Movements

Answer 1

• Depresses clavicle,
• elevates 1st rib,
• stabilizes SC joint

Question 2

Pectoralis Major Movements

Answer 2

• Adducts and medially rotates the GH joint
• Upper: Flex and horizontally adduct the GH joint
• Lower: Extends GH joint

Question 3

Pectoralis Minor Movements

Answer 3

• Depresses,
• abducts
• downwardly rotates scapula

Question 4

Serratus Anterior Movements

Answer 4

• Abduct
• upwardly rotate
• depress scapula.
• Holds medial border of scapula against rib cage

Question 5

Serratus Anterior

Origin, Insertion, Innervation, Blood Supply

Answer 5

Origin: Ribs 1-8 Distal: Anterior surface of the medial border of the scapula Innervation: Long thoracic nerve (C5, C6, C7, C8) Blood Supply: Lateral thoracic artery and subscapular artery

Question 6

Pectoralis Major

Origin, Insertion, Innervation, Blood Supply

Answer 6

• Origin: Medial 1/2 of the clavicle, sternum, and ribs 1-6
• Insertion: Crest of greater tubercle of humerus Innervation:
  
  • Upper fibers = lateral pectoral (C5, C6, C7);
  • Lower fibers = lateral and medial pectoral (C6, C7, C8 and T1)
• Blood Supply: Pectoral artery (from thoracoacromial trunk and the lateral thoracic artery)

Question 7

Subclavius

Origin, Insertion, Innervation, Blood Supply

Answer 7

• Origin: Rib 1 and cartilage
• Insertion: Inferior surface of middle 1/3 of the clavicle
• Innervation: Subclavian (C5, C6)
• Blood Supply: Clavicular artery and suprascapular artery

Question 8

Pectoralis Minor

Origin, Insertion, Innervation, Blood Supply

Answer 8

• Origin: 3rd, 4th, and 5th ribs
• Insertion: Coracoid process of the scapula
• Innervation: Medial pectoral nerve (C6, C7, C8, T1)
• Blood Supply: Pectoral artery (from thoracoacromial trunk)