Muscles of shoulder and back Flashcards
What is the function of pectoralis major?
Adducts, medialoly rotates and stansversely adducts arm at glenohumeral joint
Depresses shoulder girdle at acromioclavicular and sternoclavicular joints
What is the origin and insertion of pectoralis major?
Origin: Sternal and clavicular heads
Insertion to the crest of greater tubercle of humerus
WHat innervates the pectoralis major muscle
Medial and lateral pectoral nerves (C5-T1)
WHat supplies the pectoralis major with blood
Pectoral branches of thoracoacomial artery, branches of thoracic artery
What is the function of pectoralis minor?
Protracts and downwardly rotates shoulder girdle at actromioclavicular and sternoclavicular joints
What are the origins and insertions of pectoralis minor?
Origins: Anterior ends of 3rd to 5th ribs
Insertion: coracoid process of scapula
What are the innervation of pectoralis minor?
Medial and lateral pectoral nerves (C5 to T1)
What supplies blood to pectoralis minor?
Pectoral and deltoid branches of thoracoacromial artery, superior and lateral thoracic arteries
What are the origins/insertion of the deltoid muscle?
Origin: Lateral 1/3 of clavicle: Acromion and spine of scapula
Insertion: Deltoid tuberosity of humerus
What is the function of the deltoid?
Abducts, flexes, extends, medially rotates and laterally rotates arm at glenohumeral joint
What innervates the deltoid
Axillary nerve (C5-C6)
What provides arterial supply to the deltoid
Acromial and deltoid brances of the thoracoacromial artery, anterior and posterior circumflex humeral arteries, subscapular artery, deltoid branch of deep brachial artery
What are the origins/insertions of the trapezius muscle
Origin: Spinous processes of C7 to T12, External occipital protruberance
What are the actions of the trapezius?
Elevates, depresses, retratcs and upwardly rotates pectoral (shoulder girdle) at acromioclavicular and sternoclavicular joints, extends and laterally flexes head and neck
What innervates the trapezius?
Accessory nerve, anterior rami of third and fourth cervical nerves
What supplies the trapezius with blood
Occipital artery transverse cervical artery, dorsal scapular artery
What are the origins/insertions of serratus anterior?
Origin: External surfaces of the first to ninth ribs
Insertion: Medial border of scapula
What is the action of serratus anterior?
Protracts and upwardly rotates the pectoral girdle at acromioclavicular and sternoclavicular joints
What innervates serratus anterior?
Long thoracic nerve (C5-C7)
What supplies serratus anterior with blood?
Superior and lateral thoracic arteries, thoracodorsal artery
What are the origins/insertions of biceps brachii
Origin: Supraglenoid tuberlce of scapula, apex of coracoid process of scapula
Insertion: Radial tuberosity, antebrachial fascia
What is the function of the biceps brachii?
Flexes forearm at elbow joint, supinates forearm at radioulnar joint
What innervates biceps brachii
Musculocutaneous nerve (C5-C6)
What supplies the biceps brachii with blood
Brachial artery, anterior circumflex humeral artery
