1. Axial Musculature Biology 223 Human Anatomy and Physiology I
Week 5; Lecture 2; Wednesday
Dr. Stuart S. Sumida
Axial Musculature

3. Superficial Layer Erector Spinae Spinalis Insertion = spinous
Origin = sacrum/iliac crest
Spinalis
Insertion = spinous
processes

4. Superficial Layer Erector Spinae Longissimus Insertion = transverse
Origin = sacrum/iliac crest
Longissimus
Insertion = transverse
processes

5. Superficial Layer Erector Spinae Insertion = ribs
Origin = sacrum/iliac crest
Iliocostalis
Insertion = ribs

7. Intermediate Layer Multifidus Insertion = spinous processes
Origin = sacrum/iliac crest
Insertion = spinous processes

8. Intermediate Layer Semispinalis processes Insertion =spinous
Origin = transverse
processes
Insertion =spinous
Semispinalis has regional
designations:
Semispinalis capitus (head)
Semispinalis cervicis
Semispinalis thoracis

10. Short slips of muscle, connecting adjacent vertebrae
Deep Layer
Short slips of muscle, connecting adjacent vertebrae

13. Three Divisions
Body Wall
Limbs
Prevertebral

14. Subdivision of Body Wall Group
Abdominal
Thoracic
Perineal
Neck

16. Subdivision of the Abdominal Group
Superficial =
external Oblique
Origin: Lower 8 ribs
Insertion: top of rectus sheath

17. Subdivision of the Abdominal Group
Intermediate =
Internal Oblique
Origin: Iliac crest
Insertion: Rectus sheath

18. Subdivision of the Abdominal Group
Deep = Transversus
Origin: Thoracolumbar
fascia
Insertion: Sheath below
abdominus rectus

20. Subdivision of the Thoracic Group
External intercostal
Internal Intercostal
Transversus thoracis

24. Subdivision of the Perineal Group
Superficial = Urogenital/anal
External sphinceters

25. Subdivision of the Perineal Group Intermediate = Pelvic Diaphragm:
- Coccygeus
- Levator ani

26. Subdivision of the Perineal Group Deep = Transversalis Fascia

30. Subdivision of the Neck Region
Diaphragm ripped out early in development
Scalenes are what are left.

34. Strap muscles
Rectus Abdominus

41. Strap muscles
Pyramidalis

42. Strap muscles
Rectus Series
Geniohyoid

43. Strap muscles
Rectus Series
Omohyoid

44. Strap muscles
Rectus Series
Sternohyoid
Sternothyroid