Abdominal and Back Muscles

quadratus lumborum

Origin- 12th rib, tran processess L1-L4 Insertion- iliac crest Innervation- ant. rami T12-L4 Action- lateral flexion, hikes hip

Rectus abdominis

Origin- costal cartilage 5-7/xiphoid process, Insertion- pubic synthesis Innervation- ant rami T7-T12 Actions: trunk flexion; post pelvis tilt

Iliopsoas

Origin- iliac fossa, trans process T12-L5 Insertion- lesser trochanter Innervation- ant. rami, femoral n. L2-L4 Action: Flexion

Suboccipitals

Origin- spinous process C1 & C2 Insertion- occiput Innervation- post. rami Action:extend head on upper cervical

erector spinae

Origin-broad tendon from iliac crest; lumbar spinous process Insertion: lower ribs; transverse process thoracic & cervical Innervation: post rami Action: unilat - lat flex of trunk & neck bilat - extension of trunk & neck

Multifidus

Origin-sacrum & transverse process C2-L5 Insertion- spinous process C2-L5 Innervation- pot. rami Action- unilat - rotation to opposite bilat - trunk extension

Serratus Anterior

Saw toothed muscle that abducts the scapula

subcostal

Superior Attachment: Internal surface of lower ribs near their angles Inferior attachment: superior borders of 2nd or 3rd ribs below Innervation: Intercostal nerve Action: probably the same as intercostal muscles

Aponeurosis

strong sheet of tissue that acts as a tendon to attach muscles to bone

Scalenes

Anterior Origin: Transverse Process of C3-7 Insertion: Rib 1 (anterior & middle), 2nd rib (posterior) Innervation: ant. rami Actions: unilat - lateral neck flexion bilat - neck flexion; elevate ribs during forced inspiration

Diaphragm

Breathing, increase or decrease size of thoracic cavity, insertion- centeral tendon, origin-lumbar vertebrae

External oblique

Origin-lower 8 ribs Insertion- ant iliac crest; aponeurosis Innervation-ant rami T7-T11 Actions: unilat - lat flexion; rotate opposite bilat - forward flexion

Internal oblique

Origin-ribs 10-12 Insertion- iliac crest; aponeurosis thoracolumbar fascia Innervation-ant rami T7-L1 Actions: unilat - lat flexion; rotate same side bilat - forward flexion

Sternocleidomastoid

Origin: Clavicular head- medial 1/3 clavicle, sternal head- sternum Insertion: mastoid process & occiput Innervation: CN XI- Spinal access Actions: Unilateral- lateral flex to same, rotate head & neck to opposite Bilateral- lower cervical flexion

Splenius Cervicis

Origin: Spinous processes of T3-T6. Insertion: Transverse Processes of C1 - C3. Innervation: Post Rami Action: unilat - lat flex rotation to same (head) bilat - neck extension

Transverse abdominis

Origin: iliac crest; internal surface lower ribs Insertion: aponeurosis Innervation: ant rami T7-L1 Actions: stabilizes lumbar spine & SI joint

splenius capitis

Origin: nuchal ligament, spinous processes of vertebrae C7-T4 Insertion: mastoid process, lat occiput Innervation: post rami Action: unilaterally: lat flexion to same side bilaterally: extend head when acting

Semispinalis *

Origin:transverse process C4-T12 Insertion: spinous process C4-T6 Innervation: post rami Action: unilat - rotate to opposite bilat - extension of trunk & neck

transversus thoracis

Superior Attachment: Posterior surface of lower sternum Inferior attachment: Internal surface of costal cartilages 2-6 Innervation: Intercostal nerve Action: weakly depresses ribs

Serratus Posterior Inferior

Superior Attachment: inferior boarders of 8-12th ribs near their angles Inferior attachment: spinous process of T11-L2 Innervation: 9-11th intercostal nerves, subcostal nerves Action: depress ribs Notes: Deepest layer of superficial back muscles

Serratus Posterior Superior

Superior Attachment: nuchal ligament, spinous process of C7-T3 vertebrate Inferior attachment: superior boarders of 2nd - 4th ribs Innervation: Intercostal nerves 2-5th Action: elevate ribs

Levatores Costarum

Superior Attachment:Transverse process of T7-11 Inferior attachment: subjacent ribs between tubercle and angle Innervation: Posterior rami of C8-Tll Action: elevate ribs

Innermost Intercostal

Superior attachment- inferior border of ribs Inferior border- superior border or ribs below. Innervation- intercostal nerves Action-Depresses rib cage

Internal intercostals

Superior attachment- inferior border of ribs Inferior border- superior border or ribs below. Innervation- intercostal nerves Action-Depresses rib cage

External intercostals

Superior attachment- inferior border of ribs Inferior border- superior border or ribs below. Innervation- intercostal nerves. Action- elevate ribs during forced inspiration