04/18/2023
📚Muscle Monday📚
💥Erector Spinae Group💥
*Spinalis
*Longissimus
*Iliocostalis
The Erector Spinae Group runs from the sacrum to the occiput along the posterior aspect of the vertebral column. It’s musculature has a dense, layered arrangement that can be difficult to visualize. It might simplify matters if you imagine your Erector Spinae muscles as a tall poplar tree with three main branches- the Spinalis, Longissimus and Iliocostalis. These branches can then be subdivided into numerous, smaller branches such as Spinalis Thoracis, Longissimus Capitis, Iliocostalis Lumborum and more.
In the lumbar region, the Erectors lie deep to the thin but dense thoracolumbar aponeurosis. In the Thoracic and Cervical areas, they are deep to the Trapezius, the Rhomboids and the Serratus Posterior Superior and Inferior. As a group, the Erectors are easily palpated along the entire length of the back and neck; locating a specific branch of the Erectors, however, can be challenging.
💥Erector Spinae Group💥
▶️Action
Unilaterally
*Laterally flex vertebral column to the same side
Bilaterally
*Extend the vertebral column
↔️Origin
*Common tendon (thoracolumbar Aponeurosis) that attaches to the posterior surface of the sacrum, iliac crest, spinous processes of the lumbar and last two thoracic vertebrae
↔️Insertion
*Various attachments at the posterior ribs, spinous and transverse processes of the thoracic and cervical vertebrae and mastoid process of the temporal bone
This week we are looking at💥Iliocostalis💥
The lateral Iliocostalis and (thick Longissimus) form a visible mound alongside the lumbar and thoracic spine. The upper fibres of Longissimus and Iliocostalis muscles assist in extension, lateral flexion and rotation of the head and neck to the same side. The long tendons of Iliocostalis extend laterally beneath the scapula
↔️Origin
*Common tendon (Lumborum)
*Posterior surface of ribs 1-12 (thoracis and cervicis)
↔️Insertion
*Transverse processes of lumbar vertebrae 1-3 and posterior surface of ribs 6-12 (Lumborum)
*Posterior surface of ribs 1-6 (thoracis)
*Transverse processes of lower cervicals (cervicis)
*Trail Guide to the Body, Andrew Biel