Exam 2 thorax muscles (copy)

muscles of neck extension

rectus capitis posterior major

rectus capitis posterior minor

semispinalis capitis

splenius capitis

longissimus capitis

trapezius

muscles of neck lateral flexion

trapezius

scalene anterior

scalene medius

scalene posterior

muscles of neck flexion

longus capitis

rectus capitis anterior

SCM (both contracting)

muscles of neck rotation- same side

rectus capitis posterior major and minor

splenius capitis

splenius cervicis

muscles of neck rotation- oppositie side

SCM

semispinalis capitis

Sternocleidomastoid (SCM)

origin: two heads

-sternal head: anterior surface of manubrium of sternum

-calvicular head: superior surface of medial 1/3 of clavicle

insertion: mastoid process

innervation:

- motor- spinal portion CN XI

-pain/pripriooception- C2 and C3

action:

-bilaterally- flexion of head, elevate sternum during forceful inhalation

-unilaterally- rotate had towards opposite side of contracting muscle

Trapezius

origin: occipital protuberance and C7-T12 spinous processes

insertion: clavicle, acromion process, scapula

innervation: CN XI, C3 and C4

action: upper fibers- retracts/adducts, elevates, and rotates scapula

lower fibers- depresses scapula

Infraspinatus

origin: infraspinatus of scapula

insertion: greater tubercle of humerus

innervation: suprascapular nerve

action: lateral rotation of arm, stabilizes humerus

Rhomboid Major

origin: spinous processes of T2-T5

insertion: medial border of scapula, inferior to the insertion of rhomboid minor

innervation: dorsal scapular nerve (C4 and C5)

action: retract/adduct scapula, downward rotation of scapula to depress glenoid cavity, fixes scapula to thoracic wall

Rhomboid Minor

origin: spinous processes of C7-T1

insertion: medial border of scapula, superior to insertion of rhomboid major

innervation: dorsal scapular nerve (C4-C5)

action: retract/adduct and downward rotation of scapula, fix scapula to thoracic wall

Teres Major

origin: posterior aspect of inferior angle of scapula

insertion: humerus

innervation: lower sup scapular nerve (C5 -C6)

action: adduct humerus, medial rotation of humerus, extend humerus form flexed position, protract/abduct scapula, depress shoulder

Teres Minor

origin: lateral border of scapula

insertion: greater tubercle of humerus

innervation: axillary nerve

actions: lateral (upward) rotation of arm, stabilizes humerus

Splenius Capitis

origin: C7-T4 spinous processes

insertion: mastoid process

innervation: C3, C4

action: bilaterally- extend/hyperextend head and neck

unilaterally- laterally flex and rotate face to same side

Splenius Cervicis

origin: T3-T6 spinous processes

insertion: transverse processes C1-C3

innervation: C5-C6

action: bilaterally - extend neck

unilaterally- laterally flex and rotate neck toward same side

Latissimus Dorsi

origin: T7-T12, L1-L5 spinous processes and iliac crest

insertion: humerus

innervation: thoracodorsal N (C6-C8)

action: extension, adduction, and medial rotation of shoulder joint

Levator Scapulae

origin: C1-C4 transverse processes

insertion: scapula

innervation: C3-C5

action: elevate scapula

erector spinae- lateral column

iliocostalis lumborum

iliocostalis thoracis

iliocostalis cervicis

erector spinae- intermediate column

longissimus thoracis

longissimus cervicis

longissimus capitis

erector spinae- medial column

spinalis thoracis

spinalis cervicis

spinalis capitis

Erector Spinae muscle group

action: bilaterally- extend vertebrae column

unilaterally- rotate vertebrae column, lateral flexion

Iliocostalis Lumborum

origin: ribs 6-12, lateral crest of sacrum, medial end of iliac crest, vertebrae L1-L4

action: extend and laterally flex vertebral column

Iliocostalis Thoracis

origin: ribs 6-12

insertion: ribs 1-6, transverse process of C7

action: extend and laterally flex vertebral column

Iliocostalis Cervicis

origin: ribs 3-6

insertion: transverse process of C4-C6

action: extend and laterally flex vertebral column

Longissimus Thoracis

origin: transverse process of L1-L5

insertion: transverse process of T1-T12, ribs 9-10

action: extend head

Longissimus Cervicis

origin: transverse process of T1-T5

insertion: transverse process of C2-C6

action: extend head

Longissimus Capitis

origin: transverse process of T1-T5 and C4-C7

insertion: mastoid process

action: extend head

Spinalis Thoracis

origin: spinous process of T11-L2

insertion: spinous process of T-14

Spinous Cervicis

Origin: spinous process of C2-T2

Insertion: spinous process of C2

Action: extend head

Spinous Capitis

Origin: C4-C6

Insertion: occipital bone

Action: extend head

Serratus Posterior Inferior

Origin: T11-L2

Insertion: ribs 9-12

Innervation: intercostal nerves

Action: depress lower ribs aiding in inspiration

Serratus Posterior Superior

origin: spinous processes of vertebrae C7-T3

insertion: upper borders of ribs 2-5

innervation: 2-5 intercostal nerves

action: raise upper ribs aiding in inspiration

Pectoralis Major

Origin: anterior borer of medial half of clavicle, anterior surface of sternum, superior six costal cartilages

Insertion: bicipital groove of humerus

innervation: C5-T1

actions: flex, extend, adduct, and medially rotate humerus; draw scapula anterior and inferior

Pectoralis Minor

origin: ribs 3-5

insertion: medial border and superior surface of coracoid process of scapula

innervation: medial pectoral nerve C8, T1

action: stabilize scapula by drawing inferior and anterior against thoracic wall, raises ribs in inspiration

Serratus Anterior

origin: outer surface ribs 1-8

insertion: costal aspect of medial margin of scapula

innervation: long thoracic nerve (from roots of brachial plexus C5-C7)

action: protract/abduct and stabilize scapula, assist in upward rotation of scapula

Transversus Thoracis

origin: body of sternum, xiphoid process

insertion: ribs/costal cartilages 2-6

innervation: intercostal nerves

action: depress ribs

diaphragm anterior muscle fibers insertion

xiphoid process

diaphragm lateral muscle fibers insertion

ribs 6-12

diaphragm posterior muscle fiber insertion

T12-L3

Diaphragm sternal attachment

xiphoid process

diaphragm costal attachment

lower 6 ribs (6-12)

costal cartilages

diaphragm vertebral attachment

bodies of lumbar vertebrae

-right crus - higher (liver)

-left crus

medial arcuate ligament of diaphragm

body to transverse process of L1

passes over psoas major muscle and sympathetic trunk

lateral arcuate ligament of diaphragm

transverse process L1-12th rib

passes over quadratus lumborum muscle

Diaphragm Innvervation

phrenic nerve (C3-C5)

lower intercostal nerves (peripheral)- sensory only

Throracic wall muscles

(innermost intercostal, internal intercostal, external intercostal)

origin: upper limb muscles attach to thoracic cage

innervation: intercostal nerves, posterior rami of T1-T11

action: elevate ribs during inspirations, depress ribs

External Intercostal Muscles

origin: ribs 1-11

insertion: ribs 2-12

action: responsible for elevation of ribs, aid in quiet and forced inhalation

Internal Intercostal muscles

origin: ribs 1-11

insertion: ribs 2-12

action: depression of ribs, decreasing transverse dimensions of thoracic cavity, aid in forced expiration and coughing

muscles of forced inspiration

serratus posterior superior

serratus posterior inferior

scalene muscle group

external intercostal muscle group

levatores costarum

diaphragm

SCM

trapezius

accessory muscles of forced inspiration

scalene muscle group

SCM

Ala nasi

anterior/middle/posterior scalene

origin: C2-7

Insertion: 1st and 2nd ribs

Action: elevate ribs and rotate neck

innervation: C4-C8

muscles of forced (active) expiration

internal intercostal

abdominal muscles

muscles of quiet expiration

none :)

muscles of quiet inspiration

external intercostals, diaphragm