1. Muscles of the Human Body

2. Over 600 in the human body
Allow the skeleton to move
To cause movement, both ends of each muscle must be attached to bone
Origin or proximal attachment – the attachment closer to the center of the body
Insertion or distal attachment – the attachment away from the center of the body

3. Facial Muscles

4. Various functions of the facial muscles
Enable you to change expression and display your emotions outwardly
Allow you to close your eyes and blink
Essential for opening and closing the mouth for:
Keeping food in the mouth
Allowing you to chew
Allowing you to form words
Tongue
Function:
Allows you to move food around in your mouth and get it to a position to be swallowed
Allows you to pronounce words and speak intelligently

5. Neck Muscles

6. Neck Muscles
There are muscles posterior, lateral and anterior to the neck or cervical region
These muscles
Maintain the position in which the sits on the 1st cervical vertebra (atlas) i.e. they hold up our head
Also permit a wide range of movement

7. Sternocleidomastoids
The most important anterior pair of muscles
Movements:
Acting together, they flex the head toward the chest
Individually, each muscle tilts the face up and toward the opposite side

8. Erector Spinae muscles
Important posterior neck muscles
Attach to sacrum inferiorly and to the skull superiorly
Maintain your erect position
Therefore they are also called anti-gravity muscles
When someone faints, these muscles no longer function and the body falls face forward to the ground

9. Trapezius, Upper fibres
Important lateral neck muscles
Movements:
Acting alone, tilt the head to the same side
Together they assist in neck extension

10. Muscles of the pectoral Girdle

11. Muscles acting to hold the pectoral girdle to the chest wall:
Anterior
Pectoralis major
Pectoralis minor
Subclavius
Serratus anterior
Posterior
Trapezius
Latissimus Dorsi
Levator scapulae
Rhomboids Major & Minor

12. Pectoral Girdle - Anterior

13. Pectoral Girdle - Posterior

14. Muscles which attach from the scapula to the humerus, and act across the shoulder Joint
Anterior
Subscapularis
Posterior
Supraspinatus
Infraspinatus
Teres minor
Teres major
Lateral
Deltoid

15. Anterior Lateral Anterior deltoid Fibers Posterior deltoid Fibers
Middle Deltoid fibers

16. Superior and Posterior

17. Muscles of the Arm

18. Anterior Compartment Biceps Brachii Attaches Movements:
Proximally to distal part of humerus (short head)
Distally to proximal part of ulna (together with long head)
Movements:
Flexor of the elbow joint
Supinator of the forearm

19. Anterior Compartment cont’d
Brachialis
Attaches
Proximally to the anterior surface of the humerus
Distally to the coronoid process of the Ulna
Movements of the arm
Powerful flexor of the elbow joint
Works along with the biceps Brachii

20. Posterior compartment
Triceps Brachii
Attaches
Proximally to the humerus (medial and lateral head)
Distally to the olecranon process of the ulna (together with long head)
Movement of the arm:
Elbow extensor

21. Muscles of the Forearm

22. Forearm muscles act on the elbow, wrist and digits (fingers
Flexor-pronator group
Attached to the medial epicondyle of the humerus
Extensor- supinator
Attached to the lateral epicondyle of the humerus

24. Muscles of the pelvic girdle

25. Anterior muscles

26. Posterior and lateral muscles
Gluteals
-include 3 muscles
Gluteus maximus
-the largest of the three
-principal extensor of the hip
Gluteus medius and minimus
-assist in hip extension
-abduct the hip

27. Thigh Muscles Medial Compartment Pectinueus Gracilis Adductors:
Adductor longus
Adductor brevis
Adductor magnus
Primary action

28. Anterior Compartment Sartorius Quadriceps Extend at the knee
Rectus femoris
Vastus Lateralis
Vastus Intermedius
Vastus Medialis
Extend at the knee
Sartorius and Rectus
femoris also flex at the hip

29. Posterior Compartment
Hamstrings
-biceps femoris
-semitendinosus
-semimembranosus
Attach
-proximal to the ischial
tuberosity
-distally, biceps femoris to the
head of the fibula and the semitendinosus
and semimembranosus to the tibia
Flex at the knee
Also extend at the hip

30. Leg Muscles Anterior Compartment Tibialis Anterior
Extensor hallucis longus (deep)
Extensor digitorium (deep)
Arise from
-anterolateral surface of the tibia
-interosseous membrane between
the tibia and fibula
-anterior surface of the fibula
Cross to the ankle joint
Attach distally to
-medial side of the foot
-distal phalanges of the digits
Movements:
-primarily dorsi-flexors of the ankle
-extensors of the toes
-Tibialis anterior further inverts the foot
-Peroneus tertius assist in eversion

31. Lateral Compartment Peroneus Longus Peroneus Brevis
Proximaly attach to the
lateral surface of the tibia
Pass behind the lateral malleolus
Distally attach to the foot
Movement
-plantar flexors
-everters of the sole of the foot

32. Posterior Compartment
Superficial Group
Gastrocnemius
-has two proximal heads
-proximally attaches to the medial
and lateral epicondyles of the distal
femur
Soleus
-proximally attaches to head proximal
ends of tibia and fibula
Gastroc and soleus come together to
form an achilles tendon
Principal plantar flexors of the ankle
Deep Group – primary role is flexion of the toes
- assist in plantar flexion of the ankle

33. Obliques External oblique Internal oblique Transverse abdominus
Reach from the vertebral column,
ribs, and hip bone posteriorly
Meet in the midline anteriorly
through rectus abdominus
Functions:
Lateral bending of the abdomen
Rotation of the abdomen
Extension of the abdomen during forced inspiration
Allow the development of pregnant uterus
Contract to help expel fecal contents from the rectum

34. Muscles of the Abdomen Rectus Abdominus Paired midline muscles
Powerful flexor of the anterior abdominal wall
Strengthening of the abdominal muscles is a very important part of back therapy, because the abdominals support the back

35. Summary
Human anatomy deals with the structures that make up the human body (structures determines function)
The bones, joints, and muscles that make up the muscoloskeletal system allow numerous movements to occur, with varying degrees of:
-motion capabilities
-strength
-flexibility
Bones provide the structural framework necessary for support
Muscles supply the power
Joints supply the mechanism that allows human movement to occur

36. Questions
Describe the anatomical position and discuss its relationship to the directional terms of the body.
What are the four major planes that bisect the body? Provide an example of a movement that occurs in each plane.
Define three types of movement and give an example of each.
Name three types of muscle. How do slow twitch and fast twitch fibers differ?
Differentiate among agonists and antagonists?
Which synovial joint allow the greatest amount of movement? The least? Explain?
Outline the components and roles of the axial and appendicular skeletons?
What structures present at the knee provide additional support to this joint? What type of joint is the knee?
What muscles are primarily responsible for maintaining an upright position?
The posterior group of leg muscles are commonly called the hamstrings. What three muscles combine to form the hamstrings? What are their functions?