Muscles Flashcards
"pertinent" innervations, origins, insertions, and actions
Trapezius Origin and Insertion
Origin: Superior nuchal line of occipital bone and spinous processes of C7-T12
Insertion: Lateral 1/3 of clavicle, acromion, spine of scapula
Trapezius Innervation
Accessory Nerve (CN XI)
Trapezius Actions
Elevates, retracts, and rotates scapula; lower fibers depress scapula
Latissimus Dorsi Origin and Insertion
Origin: spinous processes of T7-L5, thoracolumbar fascia, iliac crest, and last 3 ribs
Insertion: Humerus (intertubercular sulcus)
Latissimus Dorsi Innervation
Thoracodorsal nerve (C6-C8)
Latissimus Dorsi Actions
Extends, adducts, and medially rotates humerus at shoulder
Levator Scapulae Origins and Insertions
Origin: posterior tubercles of transverse processes of C1-C4
Insertion: medial border of scapula from superior angle to spine
Levator Scapulae Innervation
Dorsal scapular nerve and ventral rami of C3-C4
Levator Scapulae Actions
elevates scapula medially
Rhomboid Minor Origin and Insertion
Origin: nuchal ligament, spines of C7+T1 vertebrae
Insertion: medial border of scapula, spine of scapula
Rhomboid Minor Innervation
Dorsal scapular nerve (C4-C5)
Rhomboid Minor Actions
retract, elevate, and rotate scapula
Rhomboid Major Origin and Insertion
Origin: Spinous processes of T2-T5 vertebrae
Insertion: medial border of scapula; below base of spine of scapula
Rhomboid Major Innervation
Dorsal Scapular Nerve (C4-C5)
Rhomboid Major Action
retract, elevate, and rotate scapula
Splenius Capitis Origin and Insertion
Origin: nuchal ligament, spinous processes of C7-T3
Insertion: mastoid process of temporal bone and lateral third of superior nuchal line
Splenius Capitis Actions (bilateral and unilateral!)
Bilateral: extend head
Unilateral: ipsilateral side bend and rotation
Splenius Cervicis Origin and Insertion
Origin: spinous processes of T3-T6
Insertion: transverse processes of C1-C3
Splenius Cervicis Innervation
Dorsal rami of lower cervical nerves
Splenius Cervicis Action (bilateral and unilateral!)
Bilateral: extend neck
Unilateral: ipsilateral sidebend and rotation
Erector Spinae Origin and Insertion
Note: insertions for iliocostalis, longissimus, and spinalis
Origin: posterior sacrum, iliac crest, spinous processes of lower lumbar and sacral vertebrae
Insertion:
Iliocostalis: angles of lower ribs and cervical transverse processes
Longissimus: between tubercles and angles of ribs, transverse processes of thoracic and cervical vertebrae, and mastoid process
Spinalis: spinous processes of upper thoracic and midcervical vertebrae
Erector Spinae Innervation
Dorsal rami of each region
Erector Spinae Actions
Extends and laterally bends vertebral column and head
Semispinalis Origin and Insertion
Origin: transverse processes of C4-T12
Insertion: spinous processes of cervical and thoracic regions
Semispinalis Action
Extend head, neck, thorax, and rotate them to opposite side
Multifidi Origin and Insertion
Origin: sacrum, ilium, transverse processes of T1-T12, and articular processes of C4-C7
Insertion: spinous processes of vertebrae above, spanning 2-4 segments
Multifidi Action
Stabilizes the spine
Rotatores Origin and Insertion
Origin: transverse processes of C, T, and L regions
Insertion: lamina and transverse processes of C/T/L spines, spanning 1 or 2 segments
Rotatores Action
Stabilizes, extends, and rotates spine
Deltoid Origin and Insertion
Origin: lateral 1/3 of anterior clavicle, lateral acromion, and inferior edge of spine of scapula
Insertion: deltoid tuberosity of humerus
Deltoid Innervation
Anterior and posterior branches of axillary nerve (C5, C6)
Deltoid Actions
Note: clavicular part, acromial part, and spinal part
Clavicular Part: flexion + IR
Acromial Part: abduction beyond initial 15 degrees
Spinal Part: extension + ER
Supraspinatus Origin and Insertion
Origin: supraspinous fossa of scapula
Insertion: superior facet of greater tubercle of humerus
Supraspinatus Innervation
Suprascapular nerve (C5, C6)
Supraspinatus Action
initiates arm ABD, acts w/ RTC muscles
Infraspinatus Origin and Insertion
Origin: infraspinous fossa of scapula and deep fascia
Insertion: middle facet of greater tuberosity of humerus
Infraspinatus Innervation
Suprascapular Nerve (C5, C6)
Infraspinatus Action
ER (with teres minor)
Teres Minor Origin and Insertion
Origin: Upper 2 thirds of posterior surface of lateral border of scapula
Insertion: inferior facet of greater tuberosity of humerus
Teres Minor Innervation
Inferior subscapular nerve (C5, C6)
Teres Minor Action
ER
Teres Major Origin and Insertion
Origin: posterior surface of inferior angle of scapula
Insertion: medial lip of intertubercular groove of humerus
Teres Major Innervation
Inferior subscapular nerve (C5, C6)
Teres Major Action
ADD and IR
Subscapularis Origin and Insertion
Origin: subscapular fossa
Insertion: lesser tubercle of humerus
Subscapularis Innervation
Superior and inferior subscapular nerves (C5-C6)
Subscapularis Action
ADD, IR, and helps hold humerus head in glenoid fossa
Biceps brachii Origin and Insertion
Note: origin for long and short head
Origin:
Long Head: supraglenoid tubercle of scapula
Short Head: tip of coracoid process of scapula
Insertion: radial tuberosity
Biceps brachii Innervation
Musculocutaneous Nerve (C5, C6)
Biceps brachii Action
Flexes and supinates forearm and elbow
Coracobrachialis Origin and Insertion
Origin: tip of coracoid process of scapula
Insertion: middle 1/3 of medial surface of humerus
Coracobrachialis Innervation
Musculocutaneous nerve (C5, C6, C7)
Coracobrachialis Action
Flexes and adducts arm at shoulder
Brachialis Origin and Insertion
Origin: Distal half of anterior surface of humerus
Insertion: coronoid process and tuberosity of ulna
Brachialis Innervation
Musculocutaneous Nerve and Radial Nerve (C7)
Brachialis Action
Flexes forearm at elbow
Triceps brachii Origin and Insertion
Origin:
Long head: infraglenoid tubercle of scapula
Lateral head: upper half of posterior humerus
Medial head: distal 2/3 of medial and posterior humerus
Insertion: posterior surface of olecranon process of ulna
Triceps brachii Innervation
Radial Nerve (C6, C7, C8)
Triceps brachii Action
extends arm at elbow; long head stabilizes head of abducted humerus and extends/adducts arm at shoulder
Pronator Teres Origin and Insertion
Origin:
Two heads: medial epicondyle of humerus and coronoid process of ulna
Insertion: Midway along lateral surface of radius
Pronator Teres Innervation
Median Nerve (C6-C7)
Pronator Teres Actions
Pronates forearm and assists with elbow flexion
Flexor Carpi Radialis Origin and Insertion
Origin: Medial epicondyle of humerus
Insertion: Base of 2nd Metacarpal
Flexor Carpi Radialis Innervation
Median Nerve (C6, C7)
Flexor Carpi Radialis Actions
Flexes and abducts hand at wrist
Palmaris Longus Origin and Insertion
Origin: medial epicondyle of humerus
Insertion: distal half of flexor retinaculum and palmar aponeurosis
Palmaris Longus Innervation
Median Nerve (C7, C8)
Palmaris Longus Actions
Flexes hand and tenses palmar aponeurosis
Flexor Carpi Ulnaris Origin and Insertion
Origin:
Humeral Hair: medial epicondyle of humerus
Ulnar head: olecranon and posterior border of ulna
Insertion: pisiform bone, hook of hamate bone, and base of 5th metacarpal
Flexor Carpi Ulnaris Innervation
Ulnar Nerve (C7, C8, T1)
Flexor Carpi Ulnaris Actions
Flexes and adducts hand at wrist
Flexor Digitorum Superficialis Origin and Insertion
Origin:
Humeroulnar head: medial epicondyle of humerus and coronoid process of ulna
Radial head: superior half of anterior radius
Insertion: bodies of middle phalangeal bones of medial four digits
Flexor Digitorum Superficialis Innervation
Median nerve (C8-T1)
Flexor Digitorum Superficialis Actions
Flexes middle and proximal phalangeal bones of medial four digits; also flexes hand at wrist
Flexor Digitorum Profundus Origin and Insertion
Origin: medial and anterior surface of proximal three quarters of ulna, and interosseous membrane
Insertion: palmar base f distal phalangeal bones of medial four digits
Flexor Digitorum Profundus Innervation (lateral and medial part)
Medial part: ulnar nerve (C8-T1)
Lateral part: medial nerve (C8-T1)
Flexor Digitorum Profundus Actions
Flexes distal phalangeal bones of medial four digits; assists in flexion of hand at wrist
Flexor Pollicis Longus Origin and Insertion
Origin: Anterior surface of radius and interosseous membrane
Insertion: palmar base of distal phalanx of thumb
Flexor Pollicis Longus Innervation
Median nerve (anterior interosseous) (C7-C8)
Flexor Pollicis Longus Actions
flexes phalangeal bones of thumb
Pronator Quadratus Origin and Insertion
Origin: distal 1/4 of anterior ulna
Insertion: distal 1/4 of anterior radius
Pronator Quadratus Innervation
Median Nerve (anterior interosseous) (C7-C8)
Pronator Quadratus Actions
Pronates forearm
Brachioradialis Origin and Insertion
Origin: proximal 2/3 of lateral supracondylar ridge of humerus
Insertion: lateral side of distal end of radius
Brachioradialis Innervation
Radial Nerve (C5-C6)
Brachioradialis Actions
Weak flexion of forearm when forearm is midpronated
Extensor Carpi Radialis Longus Origin and Insertion
Origin: distal 1/3 of lateral supracondylar ridge of humerus
Insertion: dorsal base of 2nd metacarpal and slip to 3rd metacarpal
Extensor Carpi Radialis Longus Innervation
Radial nerve (C6-C7)
Extensor Carpi Radialis Longus Action
extends and abducts hand at wrist
Extensor Carpi Radialis Brevis Origin and Insertion
Origin: lateral epicondyle o humerus (common extensor tendon)
Insertion: dorsal base of 3rd metacarpal
Extensor Carpi Radialis Brevis Innervation
Radial Nerve (deep branch) (C7-C8)
Extensor Carpi Radialis Brevis Action
Extends and abducts hand at wrist
Extensor Digitorum Origin and Insertion
Origin: lateral epicondyle of humerus
Insertion: extensor expansions of medial four digits
Extensor Digitorum Innervation
Posterior interosseous nerve (C7-C8)
Extensor Digitorum Actions
extends medial four digits; assists in wrist extension
Extensor Digiti Minimi Origin and Insertion
Origin: lateral epicondyle of humerus (common extensor tendon)
Insertion: extensor expansion of 5th digit
Extensor Digiti Minimi Innervation
Radial nerve (posterior interosseous) (C7-C8)