Muscles of the Axial Skeleton

What is this muscle?

• Erector Spinae

• Intercostals

• Iliopsoas

• Rectus Abdominis

What is the origin of the erector spinae?

• sacrum, iliac crest, spinous and transverse processes of vertebrae, ribs

• transverse processes of all lumber vertebrae, vertebral bodies of T12-L5, ilium

• iliac crest, costal cartilages of lower 6 ribs

• pubic crest and symphysis

What is the insertion of the erector spinae?

• ribs, transverse and spinous processes of vertebrae, occipital bone

• lesser trochanter of femur

• midline

• xiphoid

What is the action of the erector spinae?

• extend and laterally flex vertebral column

• stabilize ribcage

• hip flexion

• compresses abdomen

What is this muscle?

• Internal Obliques

• External Obliques

• Internal Intercostals

• External Intercostals

What is the origin of the external obliques?

• lower 8 ribs

• iliac crest, midline

• bottom ribs

• xiphoid

What is the insertion of the external obliques?

• lower 8 ribs

• iliac crest, midline

• costal cartilages

• transverse processes

What is the action of the internal and external obliques?

• together they compress the abdomen; one side does lateral trunk flexion and rotation to the opposite side

• flexes lumbar spine, depresses ribcage, stabilizes ribcage

• hip flexion

• extend and laterally flex vertebral column

What is this muscle?

• frontalis

• temporalis

• occipitalis

• masseter

Where is the origin of the frontalis?

• galea aponeurotica

• frontal bone

• temporal bone

• zygomatic bone