1. The Muscular System: Axial Musculature
Chapter 10 Lecture
Chapter 10
The Muscular System: Axial Musculature
Frederic Martini
Michael Timmons
Robert Tallitsch

2. The axial musculature arises on the axial skeleton.
Introduction
The axial musculature arises on the axial skeleton.
It positions the head and vertebral column.
It moves the rib cage.
It does not play a role in the movement or stabilization of the pectoral or pelvic girdles or the limbs.
Roughly 60% of the skeletal muscles in the body are axial muscles.

3. Introduction
The axial muscles fall into four groups based on location and/or function:
Muscles of the head and neck:
Laughing
Talking
Frowning
Smiling
Whistling
Muscles of the vertebral column
Oblique and rectus muscles:
diaphragm
Muscles of the pelvic floor
Sucking
Chewing
Swallowing
Contractions of
the eye muscles

4. Superficial Skeletal Muscles
Figure Anterior Muscles
Figure Posterior Muscles

5. Muscles of the Head and Neck
The muscles of the head and neck can be subdivided into several groups.
Muscles of facial expression
Extra-ocular muscles
Muscles of mastication
Muscles of the tongue
Muscles of the pharynx
Anterior muscles of the neck

6. Muscles of Facial Expression
Figure 10.3a Anterior Muscles
Figure 10.4a Lateral Muscles

7. Extra-ocular Muscles Figure 10.5a Lateral, Right Eye
Figure 10.5b Medial, Right eye

8. Extra-ocular Muscles Figure 10.5c Anterior, Right Eye
Figure 10.5d Anterior, Right Orbit

9. Muscles of Mastication
Figure 10.6a Lateral Muscles
Figure 10.6b Deep Lateral Muscles

10. Muscles of the Tongue
Figure Muscles of the Tongue

11. Muscles of the Pharynx Figure 10.9a Lateral View
Figure 10.9b Midsagittal View

12. Anterior Muscles of the Neck
Figure 10.10a Anterior Muscles
Figure 10.10b Superior View

13. Muscles of the Head and Neck
Summary of the head and neck muscles
PLAY
The Head and Neck

14. Muscles of the Vertebral Column
The muscles of the back form three distinct layers:
Superficial: move the neck
Intermediate: extend the vertebral column
Deep: interconnect vertebrae

15. Muscles of the Vertebral Column: Superficial and Intermediate Layers
Figure 10.12a Superficial and Intermediate Muscles

16. Summary of the erector spinae muscles
PLAY
The Erector Spinae Muscles

17. Muscles of the Vertebral Column: Deep Layer
Figure 10.12b Intervertebral Muscles

18. Muscles of the Vertebral Column: Spinal Flexors
Figure 10.12c Anterior Vertebral Muscles

19. Oblique and Rectus Muscles
The muscles of the oblique and rectus groups lie between the vertebral column and the ventral midline.
The oblique muscles can compress underlying structures or rotate the vertebral column, depending on whether one or both sides are contracting.
The rectus muscles are important flexors of the vertebral column, acting in opposition to the erector spinae.

20. Oblique and Rectus Muscles
Figure 10.13a Anterior View
Figure 10.13b Horizontal Section

21. Oblique and Rectus Muscles: The Diaphragm
Figure 10.14a Inferior View

22. Oblique and Rectus Muscles: The Diaphragm
Figure 10.14b Superior View

23. Muscles of the Pelvic Floor
Muscles of the pelvic floor have three main functions:
Support the organs of the pelvic cavity
Flex the joints of the sacrum and coccyx
Control the movement of materials through the urethra and anus

24. Muscles of the Pelvic Floor
Figure 10.15a Female

25. Muscles of the Pelvic Floor
Figure 10.15b Male