muscles of the Upper limb Flashcards
Deltoid distal attachment
Deltoid tuberosity of humerus
Deltoid origin
Lateral third of the clavicle, acromion and spine of the scapula
Deltoid innervation
Axillary nerve C5, C6
Deltoid actions
anterior part flexes and medially rotates shoulder joint, middle abducts shoulder joint, posterior extends and laterally rotates shoulder joint
Supraspinatus proximinal attachment
supraspinous fossa of scapula
Infraspinatus proximal attachment
Infraspinatus fossa of scapula
teres minor proximal attachment
middle part of lateral border of scapula
teres major proximal attachment
Inferior part of lateral border of scapula and posterior surface of inferior angle of scapula
Subscapularis proximal attachment
Subscapular fossa (most of the anterior surface)
Supraspinatus distal attachment
Superior facet of the grater tubercle of humerus
Infraspinatus distal attachment
middle facet of the greater tubercle of humerus
Teres minor distal attachment
inferior facet of the greater tubercle of humerus
teres major distal attachment
medial lip of intertubercular sulcus of humerus
Subscapularis distal attachment
lesser tubercle of humerus
Supraspinatus innervation
Suprascapular nerve C4, C5, C6
Infraspinatus innervation
Suprascapular nerve C5, C6
Teres major innervation
lower subscapular nerve C5, C6
subscapularis innervation
Upper and lower subscapular nerves C5, C6, C7
Supraspinatus actions
Initiates and assists deltoid in abduction of shoulder joint and acts with other rotator cuff muscles
Infraspinatus actions
Laterally rotate shoulder joint help hold humeral head in glenoid cavity of scapula
teres minor actions
Laterally rotate shoulder joint, help hold humeral head in glenoid cavity of scapula
teres major actions
Adducts and medially rotates shoulder joint
Subscapularis actions
Medially rotates and adducts shoulder joint helps hold humeral head in glenoid cavity.
Teres minor innervation
Axillary nerve C5, C6
Pectoralis major Proximal attachment
Clavicular head: anterior surface of medial half of clavicle
Sternocostal head: anterior surface of sternum, superior six costal cartilages, aponeurosis of external oblique muscle
Pectoralis minor Proximal attachment
3rd to 5th ribs near their costal cartilages
Subclavius Proximal attachment
Junction of 1s rib and its costal cartilage
Serratus anterior Proximal attachment
external surfaces of lateral parts of 1st-8th ribs
Pectoralis Major distal attachment
Lateral lip of intertubercular sulcus groove of humerus
Pectoralis minor distal attachment
Medial border and superior surface of coracoid process of scapula
Subclavius distal attachment
Inferior surface of middle theird clavicle
Serratus anterior distal attachment
Anterior surface of medial border of scapula
Pectoralis major Innervation
Lateral and medial pectoral nerves, clavicular head = C5, C6, Sternocostal head = C7, C8, T1
Pectoralis minor Innervation
medial pectoral nerve C8 and T1
Subclavius innervation
Subclavian nerve C5 and C6
Serratus anterior Innervation
Long thoracic nerve C5, C6 and C7
Pectoralis major actions
Adducts and medially rotates shoulder joint, draws scapula anteriorly and inferiorly,
Acting alone clavicular head flexes shoulder joint and sternocostal head extends it from the flexed position
Pectoralis minor actions
Stabilizes scapula by drawing inferiorly and anteriorly against thoracic wall
Subclavius actions
Anchors and depresses clavicle
Serratus anterior actions
Protracts scapula and holds against thoracic wall, rotates scapula
Biceps Brachii Proximal attachment
Short head: tip of coracoid process of scapula
Long head: supraglenoid tubercle of scapula
Brachialis Proximal attachment
Distal half of anterior surface of humerus
Coracobrachialis Proximal attachment
tip of coracoid process of scapula
Triceps brachii Proximal attachment
Long head: infraglenoid tubercle of scapula
Lateral head: posterior surface of humerus, superior to radial groove
medial head: posterior surface of humerus, inferior to radial groove
Biceps Brachii Distal attachment
tuberosity of radius and fascia of forearm via bicepital aponeurosis
Brachialis Distal attachment
coronoid process and tuberosity of ulna
Coracobrachialis Distal attachment
middle third of medial surface of humerus
Triceps Brachii Distal attachment
proximal end of olecranon of ulna and fascia of forearm
Biceps brachii innervation
Musculocutaneous nerve C5, C6
Brachialis Innervation
Musculocutaneous nerve C5, C6
Coracobrachialis innervation
Musculocutaneous nerve C5, C6, C7
Triceps brachii innervation
Radial nerve C6, C7, C8
Biceps brachii actions
supinates forearm and when it is supinated flexes elbow joint; flexes shoulder joint; short head resists dislocation of shoulder
brachialis actions
flexes elbow joint in all positions
Coracobrachialis actions
Helps flex and adduct shoulder joint, resists dislocation of shoulder
triceps brachii actions
chief extensor of elbow joints; long head extends shoulder joint and resists dislocation of humerus (especially important during abduction)
Omohyoid origin
superior border of the scapula near the suprascapular notch
Omohyoid insertion
inferior border of hyoid
omohyoid innervation
C1-C3 (by a brach of ansa cervicalis)
omohyoid action
depresses, retracts, and steadies hyoid