Lumbar Muscles

Question 0

Spinalis Thoracis

Answer 0

PA: sp’s of T11-12, L1-2

DA: sp’s of T1-4

I: dorsal rami of thoracic nerves

A: bilateral trunk extension, weak ipsilateral SB

Question 1

Latissimus Dorsi

Answer 1

PA: T7-12, iliolumbar fascia, iliac crest, ribs 9-12

DA: floor of the bicepital groove

I: thoracodorsal nerve (c6-8)

A: extension, addiction, and interval rotation of the shoulder

Question 2

Longissimus Thoracis

Answer 2

PA: via the common tendon, thoracolumbar fascia, posterior surface of lumbar TPs, sacrum

DA: tps of all thoracic vertebrae, lower 8-9 ribs

I: dorsal Rami of lumbar and thoracic nerves

A: bilateral trunk extension, ipsi SB

Question 3

Iliocostalis Thoracis

Answer 3

PA: lower 6 ribs

DA: angles of the upper 6 ribs

I: dorsal Rami of the lumbar and thoracic nerves

A: bilateral trunk extension, ipsi SB

Question 4

Multifidus

Answer 4

PA: TPs of lumber through lower cervical vertebra, sacrum, PSIS, dorsal SI ligaments

DA: SP of the more superiorly located vertebrae

I: dorsal rami of corresponding level

A: trunk extension, ipsi SB, contra lateral rotation, stabilization of SI joint and lumber joints

Question 5

Rotators

Answer 5

TPs of the thoracic spine T1-12

Lamina of the next superior vertebrae

Dorsal rami of corresponding level

Trunk contra rotation and bilat extension