Muscles (Origins, Insertions, Innervation, and Action) Flashcards
Obliquus Capitis Inferior
Origin?
Insertion?
Origin: Arises from the spinous process of the C2 Vertebra
Insertion: Into the transverse process of C1
Obliquus capitis superior
Origin?
Insertion?
Origin: Arises from the spinous process of C1
Insertion: Into the occipital bone between superior and inferior nuchal lines.
Rectus capitis posterior major
Origin?
Insertion?
Origin: Arises from the spinous process of the C2 vertebra
Insertion: Into the lateral part of the inferior nuchal line of the occipital bone
Rectus capitis posterior minor
Origin?
Insertion?
Origin: Arises from the posterior tubercle on the posterior arch of the C1 vertebra
Insertion: Into the medial third of the inferior nuchal line
Supraspinatus Origin? Insertion? Innervation? Action?
Origin: Supraspinous fossa
Insertion: superior facet of greater tubercle of the humerus
Innervation: Subscapular nerve (C4,5,6)
Action: Assist/ initiates deltoid abduction of shoulder joint
Infraspinatus Origin? Insertion? Innervation? Action?
Origin: Infraspinous fossa
Insertion: middle facet of greater tubercle
Innervation: Suprascapular nerve C5, 6
Action: Laterally rotates shoulder joint, helps hold humeral head in glenoid cavity
Subscapularis Origin? Insertion? Innervation? Action?
Origin: Subscapular fossa
Insertion: lesser tubercle
Innervation: Upper and lower subscapular nerve (C5,6,7)
Action: Medially rotates and adducts shoulder joint, helps hold humeral head in glenoid cavity
Teres Minor Origin? Insertion? Innervation? Action?
Origin: Middle part of the lateral border of the scapula
Insertion: Inferior facet of greater tubercle
Innervation: Axillary nerve C5,6
Action: Laterally rotates shoulder joint, holds humeral head in glenoid cavity.
Teres Major Origin? Insertion? Innervation? Action?
Origin: Inferior part of lateral border of scapula and posterior surface of inferior angle of scapula
Insertion: Medial lip of intertubercular sulcus
Innervation: Lower subscapular nerve C5,6
Action: Adducts and medially rotates
Deltoid Origin? Insertion? Innervation? Action?
Origin: Lateral 1/3 of clavicle, acromion, and spine of scap
Insertion: deltoid tuberosity
Innervation: Axillary nerve C5,6
Action: Clavicle- flexes medially rotates
Acromion- abducts
Spine- extends, laterally rotates
Pectoralis Major Origin? Insertion? Innervation? Action?
Origin: Clavicular head- anterior surface of medial half of clavicle
Sternocostal head- Anterior surface of sternum, superior six costal cartilages, aponeurosis of external oblique muscle
Insertion: Lateral lip of intertubercular sulcus of humerus
Innervation: Lateral and media pectoral nerves, Clavicular head C5,6 Sternocostal head: C7,8,9
Action: Adducts, medially rotates shoulder joint, draws scapula anteriorly and posteriorly.
Clavicular head alone: flexes shoulder joint
Sternocostal head alone: extends shoulder joint from the flexed position
Pectoralis Minor Origin? Insertion? Innervation? Action?
Origin: 3-5th ribs near their costal cartilage
Insertion: Medial border and superior surface of coracoid process of scapula
Innervation: Medial pectoral nerve (C8, T1)
Action: Stabilizes scapula by drawing inferiorly and anteriorly against thoracic wall
Serratus Anterior Origin? Insertion? Innervation? Action?
Origin: External surfaces of lateral parts 1-8th ribs
Insertion: anterior surface of medial border of scapula
Innervation: Long thoracic nerve C5,6,7
Action: protracts the scapula and holds against thoracic wall, rotates scapula
Subclavius Origin? Insertion? Innervation? Action?
Origin: junction of 1st rib and its costal cartilage
Insertion: Inferior surface of middle third of clavicle
Innervation: Subclavian nerve (C5,6)
Action: Anchors and depresses the clavicle
Omohyoid Origin? Insertion? Innervation? Action?
Origin: Superior border of scapula near suprascapular notch
Insertion: Inferior border of hyoid
Innervation: C1-C3 by a branch of ansa cervicalis
Action: depresses, retracts, steadies hyoid
Biceps Brachii Origin? Insertion? Innervation? Action?
Origin: Short head: tip of coronoid process
Long Head: Supraglenoid tubercle of scapula
Insertion: tuberosity of radius and fascia of forearm via bicipital aponeurosis
Innervation: Musculocutaneous nerve (C5,6)
Action: Supinates forearm and when it is supinated, flexes elbow. Also flexes shoulder joint, short head resists dislocation of the shoulder
Brachialis Origin? Insertion? Innervation? Action?
Origin- distal half of anterior surface of humerus
Insertion: coronoid process and tuberosity of ulna
Innervation: Musculocutaneous nerve (C5,6)
Action: flexes elbow joint in all positions
Coracobrachialis Origin? Insertion? Innervation? Action?
Origin: tip of coronoid process of scapula
Insertion: Middle third of medial surface of humerus
Innervation: Musculocutaneous nerve (C5,6)
Action: Helps flex and adduct shoulder joint, resist dislocation of the shoulder
Triceps Brachii Origin? Insertion? Innervation? Action?
Origin: 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
Insertion: Proximal end of olecranon of ulna and fascia of forearm
Innervation: Radial nerve (C6,7,8)
Action: Chief extensor of elbow. LONG head: extends shoulder joint and resists dislocation of humerus (Important during abduction)
Brachioradialis Origin? Insertion? Action? Innervation
Origin- Proximal 2/3 of the lateral supraepicondylar ridge of the humerus
Insertions: lateral surface of distal end of radius proximal to styloid process
Action: Weak flexion of elbow, maximal when forearm in in midpronated positiong
Innervation: Radial nerve
Extensor carpi radialis brevis Origin? Insertion? Action? Innervatio?
Origin: Lateral supraepicondylar ridge of the humerus
Insertion: Dorsal aspect of base of 2nd metacarpal
Action: Extend and abduct wrist joint
Innervation: Radial nerve
Extensor carpi radialis brevis
Origin: Lateral epicondyle of humerus
Insertion: Dorsal aspect of base of 3rd metacarpal
Action: Extend and abduct wrist joint, active during fist clenching
Innervation: Deep branch of radial nerve
Extensor digitorum
Origin: Lateral epicondyle of the humerus
Insertion: extensor expansions of medial four fingers
Action: Extends wrist joint, extends medial four fingers primarily at metacarpophalangeal joints, secondarily at IP joints
Innvervation: Deep branch of radial nerve
Extensor digiti minimi
Origin: Lateral epicondyle of humerus
Insertion: extensor expansion of 5th finger
Action: Extends wrist joint, extends 5th finger at metacarpophalangeal joint, secondarily at IP joint
Innervation: Posterior interroseous nerve
Extensor carpi ulnaris
Origin: Lateral epicondyle of humerus, posterior border of ulna via a shared aponeurosis
Insertion: Dorsal aspect of base of 5th metacarpal
Action: Extends and adducts wrist joint, active during fist clenching
Innervation: Posterior interroseous nerve
