Erector Spine Muscle Group

Question 1

What are the three muscles of the erector spine group?

Answer 1

○ Spinalis- most medial part both originating and inserting onto SP (deepest)
○ Longissimus- slightly more laterally and originates inferiorly from posterior sacrum and inserts onto lateral TP’s
Iliocostalis- posterior part of iliac crest and inserts onto ribs

All Epimere- and Dorsal Rami

Question 2

Spinalis

Answer 2

Spinalis Capitis:
inferior attachment/ Superior usually blends with semispinalis capitis

Spinalis Cervicis:
InferiorATT - Lig Nuchae,
Sup ATT : C2 SP

Spinalis Thoracis:
inferior ATT- upper lumbar and lower thoracic SP
Superior ATT: upper thoracic SP

Question 3

Longissimus