musculoskeletal back muscles Origin insertion innervation action

trapezius muscle origin

medial 1/3 of nuchal line

EOP

SP of C7-T12

Trapezius insertion

acromion

lateral 1/3 of clavicle

scapular spine

innervation for trapezius muscle

CN XI Accessory (motor)

C3,C4 (sensory)

action of trapezius

elevates shoulders

retracts shoulders

tilts head backwards

first layer back muscles (extrinsic/superficial)

trapezius, latissimus dorsi

second layer back muscles (extrinsic/superficial)

rhomboid major, rhomboid minor, levator scapulae

third layer back muscles (intermediate/superficial)

serratus posterior inferior and serratus posterior superior

fourth layer back muscles (intrinsic/superficial)

splenius capitis and splenius cervicis

fifth layer back muscles (intrinsic/intermediate)

erector spinal muscle group

sixth layer back muscles (intrinsicdeep)

transversospinalis group

deeper than sixth layer back muscles (intrinsic/deeper)

suboccipital muscles, intertransversarii muscles and interspinales muscles

superficial muscles of the back

trapezius, latissimus dorsi, rhomboid major, rhomboid minor, levator scapulae

latissimus dorsi origin

SP of T7-T12

inferior 3-4 ribs

thoracolumbar fascia

Iliac crest

latissimus dorsi insertion

intertubercular sulcus of the humerus

latissimus dorsi innervation

Thoracodorsal nerve

action of latissimus dorsi

extends, adducts, and medially rotates the humerus

levator scapulae origin

TP of C1-C4

Levator scapulae insertion

medial border of the scapula superior to the scapular spine

innervation of levator scapulae

dorsal scapular (Motor)

C3, C4 (sensory)

levator scapulae action

elevates shoulder

retracts shoulder blades

tilt head backwards

rhomboid major origin

SP of T2-T5

Rhomboid major insertion

Medial border of Scapula from the spine to the inferior angle

Rhomboid Major innervation

Dorsal scapular Nerve

Rhomboid major action

Retract scapula, rotate glenoid cavity inferiorly, fix scapula to thoracic wall

rhomboid minor origin

SP of C7 and T1

rhomboid minor insertion

medial scapular spine

rhomboid minor innervation

dorsal scapular nerve

Rhomboid minor action

retracts scapula, rotates glenoid cavity inferiorly, fix scapula to the thoracic wall

serratus posterior superior origin

SP of C7-T3

serratus posterior superior insertion

superior border of ribs 2-4

Serratus posterior superior innervation

Intercostal nerves 2-5

serratus posterior superior action

proprioception and elevation of ribs

serratus posterior inferior origin

SP of T11-L2

serratus posterior inferior insertion

inferior border of ribs 8-12

Serratus posterior inferior innervation

intercostal nerves 9-12

serratus posterior inferior action

proprioception and depress ribs

splenius capitis origin

nuchal ligament, SP of C6-C7

splenius cervicis origin

SP of T3-T6

splenius capitis insertion

mastoid process and superior nuchal line

splenius cervicis origin

tubercles of TP of C1-C3/4

Splenius capitis and cervicis innervation

Dorsal Rami of the segments spinal nerves

splenius capitis and cervicis action

extends the head and neck, laterally flexes and rotates to side of active muscle

erector spinae muscles from lateral to medial

Iliocostalis, longissimus, spinalis

action of erector spinae group

Extensor of the back

location of erector spinae group

between the SPs and angles of ribs

Transversospinalis muscle group layers from superficial to deep

semispinalis group

multifidus group

rotatores group

muscles of the suboccipital triangle

rectus capitis posterior minor

rectus capitis posterior major

obliquus capitis inferior

obliquus capitis superior

innervation of suboccipital triangle

Suboccipital nerve (AKA posterior branch of C1 spinal nerve)

C2 dorsal ramus

Origin of rectus capitis posterior minor

posterior tubercle of the atlas (C1)

Insertion of the rectus capitis posterior minor

inferior nuchal line

action of rectus capitis posterior minor

extension of the head

rectus capitis posterior major origin

SP of the axis (C2)

Rectus capitis posterior major insertion

Lateral part of inferior nuchal line

origin of the obliquus capitis inferior

SP of Axis (C2)

insertion of the obliquus capitis inferior

TP of Atlas (C1)

origin of the obliquus capitis superior

TP of the Atlas (C1)

insertion of the obliquus capitis superior

Lateral inferior nuchal line

primary artery that supplies the suboccipital triangle

Vertebral Artery

What ligament connects the occiput to C1

Atlanto-occipital membrane

what happens when the posterior atlanto-occipital membrane ossifies

a bridge called “posterior ponticus” is formed between occiput and the atlas

what is the hole in a complete posterior ponticus called?

arcuate foramen

location of cervicis interspinalis muscles

between SP of C2-T1

Location of Thoracis interspinalis muscles

Between Sp of T1-T3 and T11-T12

Location of lumborum interspinalis muscles

Between SP of T12-S1

Location of Cervicis intertransversiarii muscle

TPs of C2-T1

Location of thoracis intertransversiarii muscle

TPs of T9-T12

Location of Lumborum intertransversiarii muscle

TPs of T12-S1

Location of levator costorum brevis

TP to Rib on C7-T11

Location of levator costorum longus

TP to rib of T8-T10

Innervation of Levator costorum longus and brevis

Dorsal rami

Muscle involved in the lumbar triangle

Latissimus dorsi, external oblique abdominus, and the iliac crest