BMS561. Lecture 2 OIANs.

OIANs of Hypaxial mm, Epiaxial mm (including Erector Spinae group), Transversospinalis mm., Suboccipital mm.

Upper Trapezius Origin and Insertion

O: external occipital protuberance, medial 1/3 of superior nuchal line, ligamentum nuchae, spinous process of C7

I: lateral 1/3 clavicle and acromion process of scapula

Actions of upper trapezius

elevation of scapula

ext, lat flex, OSR of C-spine (head)

Trapezius Innervation

Accessory (CN XI), ventral rami C2, C3, C4

Middle Trapezius Origin and Insertion

O: spinous process of T1-T5

I: medial margin of acromion and superior lip of spine of scapula

Middle Trapezius Action

retraction of the scapula

Lower Trapezius Origin and Insertion

O: spinous process of T6-T12

I: tubercle at the apex of spine of scapula

Action of Lower Trapeziu

depression of scapula, upward rotation of scapula, accessory mm. of respiration

Origin and Insertion of Latissimus Dorsi

O: spinous process of T6-T12, ribs 9-12, through the thoracolumbar fascia from lumbar and sacral vertebrae, posterior 1/3 of exteral lip of iliac crest, one slip from inferior angle of scapula

I: bed of the intertubercular groove of the humerus

Action of Latissimus Dorsi

Origin fixed:

Med rot, add, ext of the humerus

depression of the shoulder girdle

lateral flexion of the trunk

Insertion fixed:

ant/lat pelvic tilt

hyperextend spine

accessory mm. inspiration

Innervation of Lats

Thoracodorsal nerve (C6-C8)

Origin and Insertion of Rhomboid Major

O: spinous process of T2-T5

I: fibrous attachment to the medial border of scapula between the spine and inferior angle

Actions of Rhomboid Major and Minor

Elevate, retract, downward rot of scapula

Innervation of Rhomboid Major, Rhomboid Minor, and Levator Scapulae

Dorsal Scapular Nerve (C4, C5)

Origin and Insertion of Rhomboid Minor

O: ligament nuchae, spinous process of C7, T1

I: medial border at root of spine of scapula

Origin and Insertion of Levator Scapulae

O: transverse process of C1-C4

I: medial border of scapula, between superior angle and root of the spine

Action of Levator Scapulae

Ext, lat flex, SSR of C-spine

elevate scapula

assists in downward rot of scapula

OIAN of Serratus Posterior Superior

O: ligamentum nuchae, spinous processes of C7-T3

I: superior borders of ribs 2-5

A: elevate ribs 2-5 during hyperinhalation

N: T1-T4

OIAN of Serratus Posterior Inferior

O: spinous processes of T11-T12

I: inferior borders of ribs 9-12

A: depress ribs 9-12 during hyperexhalation

N: T9-T12

Innervation of Epaxial mm.

dorsal rami

OI of splenius Capitis

O: superior ½ of ligamentum nuchae, spinous process of C7, T1-T3or4

I: occipital bone inferior to the lateral 1/3 of the superior nuchal line, mastoid process of temporal bone

Action of Splenius Capitis

Ext. lat flex, SSR of C-spine

*acts on the atlanto-occipital jt, interbody jts, facet jts

OI of splenius cervicis

O: spinous process of T3-T6

I: posterior tubercle of transverse of C1-C2or3

Action of Splenius Cervicis

Ext, lat flex, SSR of neck

*acts of interbody and facet jts. of C-spine

OIA of iliocostalis lumborum

O: medial and lateral crests of sacrum, sp of T11-L5, posterior part of medial lip of iliac creast, supraspinous lig.

I: angle of ribs 6-12,

A: ext, lat flex of spine, also draws ribs downward

OIA of Iliocostalis thoracis

O: upper borders of angles of ribs 7-12

I: angle of ribs 1-6, tp of C7

A: extension, lateral flexion of spine, draws ribs downward

OIA of Iliocostalis cervicis

O: angle of ribs 3-6

I: post. tubercles of transverse processes of C4-C6

A: ext, lat flex of spine, also draws ribs downward

OI = of longissimus thoracis

O: posterior surfaces of sp and tp of L1-L5, anterior layer of thoracolumbar fascia

I: transverse process of T1-T12, ribs 3-12 between tubercles and angle

OI of Longissium Cervicis

O: transverse processes of T1-T5

I: posterior tubercles of transverse processes of C2-C6

OI Longissimus Capitis

O: tp of T1-T5, articular processes of C4-C7.

I: post. margin of the mastoid process of temporal bone deep to splenius capitis and SCM

Action of Longissimus group

Extension and lateral felxion of the spine,

Longissimus Capitis assists in SSR of neck

OIA Spinalis Thoracis

O: spinous processes of T11-T12

I: spinous processes of T2-T8

A: ext., lat flex, SSR of T-spine (Corey says only extension of spine)

Where is spinalis capitis found?

medial border of semispinalis capitis

OIA semispinalis cervicis

O: transverse processes of T1-T6

I: spinous processes of C2-C5

A: Extend, OSR in C- and upper T- spine

OIA of semispinalis Capitis

O: articular processes of C4-C6, transverse processes of C7, T1-6

I: between superior and inferior nuchal lines of occipital bones

A: extension and OSR of head

O of multifidous (2x regions)

Sacral Region:

posterior surface of sacrum, medial surface of posterior iliac spine, posterior sacro-iliac ligs

L, T, C regions

transverse process of C4-L5

Insertion of multifidous

*varies

spinous process of vertebrae that spans 2-4 vertebrae higher from origin from C2-L5

Actions of multifidous

Extension of spine, OSR of spine, Lat flex of spine

*postural / stabilization of spine

OI Rotatores

O: transverse processes of all vertebrae

I:

Brevis - base of spinous process of vert. above origin

Longus - base of spinous process two vert. above origin

Action of rotatores

OSR, ext, stabilization of spine

Interspinales OIA

How many pairs are in each section of the spine?

O: spinous process of vertebrae

I: adjacent superior spinous process

A: extend spine

C: 6 pairs

T: 2-3 pairs (bw T1-T2 and T11-T12)

L: 4 pairs

Intertransversarrii OIA

O: transverse process

I: adjacent transverse process

A: postural, slight lat flex

Levator Costarum OIAN

O: transverse process of C7-T11

I: angle of rib

A:

elevate rib during inspiration

when rib is fixed, lat flex of spine, ext of spine

N: Intercostal nn.

OIA RCPM

O: spinous process of axis

I: lateral part of inferior nuchal line of occipital bone

A: SSR of head (AO jt?)

Innervation of the suboccipiral mm

suboccipital n (CN1)

Rectus Capitis Posterior Minor OIA

O: tubercle on posterior arch of atlas

I: medial part of inferior nuchal line of occipital bone

A: Postural - erect skull at atlanto-occipital jt

Obliquues Capitis Inferior OIA

O: apex of spinous process of axis

I: inferoposterior part of transverse process of C1

A: SSR at AO jt

Obliquus capitis superior OIA

O: superior surface of tp of atlas

I: bw sup and inf nuchal lines of occiptial bone

A: extend spine at AO jt