Posterior Muscles

Question 1

What makes up erector spinae

Answer 1

Longissimus thoracis and iliocostalis lumborum

Question 2

Superficial layer of erector spinae

Answer 2

Long MA, good line of pull, bilat: extension in T and L regions, unilat: Lat flex trunk and rotation

Question 3

Flexion relaxation phenomenon

Answer 3

After 2/3 of maximal flexion, will become electrically silent

Question 4

Deep layer of erector spinae

Answer 4

Posterior shear, not good extensors, impressive forces, not good at resisting anterior shear force with flexion

Question 5

Multifidus

Answer 5

Extension, increases lordosis, compression, rotation to oppose flexion moment that abs produce

Question 6

1. Intertransversarii and 2. rotatores muscles

Answer 6

1. Lateral flexion 2. rotation and both. Proprioception

Question 7

What 3 structures will compress the lumbosacral region and will make it stable

Answer 7

Latissimus dorsi, contralateral glut max, thoracolumbar fascia