Muscle Chart: Erector Spinae

Question 1

Iliocostalis

Origin, Insertion, Innervation, Blood Supply

Answer 1

Origin: Common tendon

Insertion: transverse processes L1-L3 and lower 1/2 ribs (lumborum), posterior surface of ribs 1-12 (thoracis) and transverse processes C4-6 (cervicis)

Innervation: Dorsal rami of the spinal nerves

Blood Supply: Intercostal arteries

Question 2

Iliocostalis Movements

Answer 2

Unilaterally: laterally flexes the vertebral column to same side

Bilaterally: Extend vertebral column

Question 3

Longissimus

Origin, Insertion, Innervation, Blood Supply

Answer 3

Origin: Common tendon and transverse processes of upper five thoracic vertebrae

Insertion:

• Thoracis: lower 9 ribs and transverse processes of thoracic vertebrae
• Cervicis: Transverse processes of cervical vertebrae
• Capitis: Mastoid process of temporal bone

Innervation: Dorsal rami of the spinal nerves

Blood Supply: Intercostal arteries

Question 4

Longissimus Movements

Answer 4

Unilaterally: Laterally flexes the vertebral column to same side

Bilaterally: Extend vertebral column

Question 5

Spinalis

Origin, Insertion, Innervation, Blood Supply

Answer 5

Origin and insertion not specified
Thoracis: Spinous processes of upper lumbar and lower thoracic vertebrae, lower 9 ribs and transverse processes of thoracic vertebrae

Cervicis: Ligamentum nuchae and spinous processes of C7, transverse processes of cervical vertebrae

Capitis: Mastoid process of temporal bone

Innervation: Dorsal rami of the spinal nerves

Blood Supply: Intercostal arteries

Question 6

Spinalis Movements

Answer 6

Unilaterally: Laterally flexes the vertebral column to the same side

Bilaterally: Extend vertebral column