Erector Spinae Longissimus
O: Thoracolumbar fascia, iliac crest, posterior sacrum, sacral ligaments, SP of lumbar vertebrae
I: Between tubercles of ribs 3-12, TP of thoracic and cervical vertebrae, mastoid process
N: Respective spinal nerves of each region
A: Laterally flexes column to same side, bilaterally extends vertebral column