Anatomy Trunk Packet

Rectus Abdominis origin

pubic crest, pubic symphysis

Rectus Abdominis insertion

costal cartilages 5-7, xiphoid process

Rectus Abdominis action

flexes trunk

Rectus Abdominis innervation

ventral rami of spinal nerves T5-T12

Transverse Abdominis origin

lower 6 ribs, thoracolumbar fascia (attached to TP of lumbar vertebrae), iliac crest, inguinal ligament

Transverse Abdominis insertion

linea alba, pubic crest

Transverse Abdominis action

stabilize trunk via fixation of linea alba

compress abdomen

Transverse Abdominis innervation

ventral rami of spinal nerves T7-T12, iliohypogastric and ilioinguinal nerve networks

External Abdominal Oblique origin

external surface of ribs 5-8 (anterior fibers) and ribs 9-12 (lateral fibers)

External Abdominal Oblique insertion

outer lip of iliac crest, linea alba via aponeurosis

External Abdominal Oblique action

bilaterally- flex trunk; lateral fibers act on lumbar region to tilt pelvis posterior

unilaterally- rotate to opposite side

compress abdomen

External Abdominal Oblique innervation

ventral rami of spinal nerves T5-T12

Internal Abdominal Oblique origin

lateral 2/3 of inguinal ligament, iliac crest, thoracolumbar fascia

Internal Abdominal Oblique insertion

crest of pubis, pectineal line, linea alba

Internal Abdominal Oblique action

upper anterior fibers flex trunk

unilaterally- work with external oblique of opposite side to rotate trunk

Internal Abdominal Oblique innervation

ventral rami of spinal nerves T7-T12, iliohypogastric and ilioinguinal nerve networks

Obliquus Capitis Superior origin

TP of C1

Obliquus Capitis Superior insertion

occipital bone deep to Spinalis Capitis and Spinalis Cervicis and superficial to Rectus Capitis Posterior Major and Rectus Capitis Posterior Minor

Obliquus Capitis Superior action

extension of AO and a bit of lateral flexion (as a stabilizer of the occiput on C1- the rotation is of the unit, performed primarily at C1/C2)

Obliquus Capitis Superior innervation

dorsal rami of C1 (Suboccipital Nerve)

Obliquus Capitis Inferior origin

SP of C2, lateral to Rectus Capitis Posterior Major

Obliquus Capitis Inferior insertion

TP of C1

Obliquus Capitis Inferior action

ipsilateral rotation at AA joint

Obliquus Capitis Inferior innervation

dorsal rami of C1 (Suboccipital Nerve)

Rectus Capitis Posterior Minor origin

posterior tubercle of C1

Rectus Capitis Posterior Minor insertion

occipital bone, medial to Rectus Capitis Posterior Major

Rectus Capitis Posterior Minor action

extension at AO joint

Rectus Capitis Posterior Minor innervation

dorsal rami of C1 (Suboccipital Nerve)

Rectus Capitis Posterior Major origin

SP of C2

Rectus Capitis Posterior Major insertion

occipital bone lateral to midline at Inferior Nuchal Line

Rectus Capitis Posterior Major action

extension at AO joint

ipsilateral rotation at AA

Rectus Capitis Posterior Major innervation

dorsal rami of C1 (Suboccipital Nerve)

Intrinsic Back Muscle Layers

Superficial

Intermediate

Deep

Intrinsic Superficial Muscles

Splenius Capitis

Splenius Cervicis

Intrinsic Intermediate Muscles

Erector Spinae-

Iliocostalis

Longissimus

Spinalis

Intrinsic Deep Muscles

Transversospinalis-

Semispinalis

Multifidus

Rotatores

Minor Back Muscles

Interspinales

Intertransversarius

Levator Costarum

Suboccipital Triangle contents

Suboccipital Nerve (C1)

Suboccipital Triangle borders

Obliquus Capitis Superior

Obliquus Capitis Inferior

Rectus Capitis Posterior Major

Extrinsic Back Muscle Layers

Superficial

Deep

Extrinsic Superficial Muscles

Trapezius

Latissimus Dorsi

Extrinsic Deep Muscles

Levator Scapulae

Rhomboid Major

Rhomboid Minor

Serratus Anterior

Serratus Posterior Superior

Serratus Posterior Inferior

Trapezius origin

lateral 1/3 Clavicle

Acromion, Spine of Scapula

Trapezius insertion

medial 1/3 Superior Nuchal Line

External Occipital Protuberance

Nuchal Ligament

SP of C7-T12

Trapezius action

Scapular movement- elevation, upward rotation (superior part), retraction (middle part), depression (inferior part)

Trapezius innervation

Spinal Accessory Nerve (Cranial Nerve 11)

C3-C4 via cervical plexus

Latissimus Dorsi origin

SP of T7-T12

Thoracolumbar fascia

posterior 1/3 Iliac Crest

Ribs 9 or 10-12

Latissimus Dorsi insertion

floor of Intertubercular Sulcus Humerus

Latissimus Dorsi action

Glenohumeral joint extension, adduction, internal rotation

Scapular retraction

Latissimus Dorsi innervation

Thoracodorsal Nerve (C6, C7, C8)

Serratus Anterior origin

Ribs 1-8 external and lateral parts

Serratus Anterior insertion

anterior medial border of Scapula

Serratus Anterior action

protracts Scapula, anchors to thoracic wall

Serratus Anterior innervation

Long Thoracic Nerve (C5, C6, C7)

Serratus Posterior Inferior origin

SP of T11-T12

Serratus Posterior Inferior insertion

inferior border of ribs 9-12

Serratus Posterior Inferior action

depress ribs 9-12

assist forced exhalation

Serratus Posterior Inferior innervation

Anterior Primary Rami T9-T12

Serratus Posterior Superior origin

SP C7-T12

Serratus Posterior Superior insertion

posterior aspect of ribs 2-5

Serratus Posterior Superior action

assist in forced inspiration

Serratus Posterior Superior innervation

Anterior Primary Rami T2-T5