1. The Muscular System

2. Muscle Tissue One of the four types of tissue in the body
Elongated cells
Specialized for contraction
Three types of muscle tissue:
Skeletal muscle
Cardiac muscle
Smooth muscle

3. Functions of skeletal muscle
Produce movement of the skeleton
Maintaining Posture and body position
Support soft tissues
Guard entrances and exits
Maintain body temperature by generating heat

4. Axial Musculature Positions the head and spinal column
Moves the rib cage
Does not play a role in movement or support of the pectoral girdle

5. Appendicular Musculature
Stabilizes or moves components of the appendicular skeleton

6. Muscle Terminology When a skeletal muscle contracts,
1. Origin = muscle attachment that remains fixed 2. Insertion = muscle attachment that moves 3. Action = what joint movement a muscle produces
When a skeletal muscle contracts,
its insertion moves toward its origin

7. Muscle Terminology 4. Agonist = prime mover 5. Synergist 6. Antagonist
Main muscle in an action
5. Synergist
Helper muscle in action
6. Antagonist
Oppose or reverse a movement
When agonists are in action, antagonists are relaxed
7. Fixator
Stabilize the origin of a prime mover
Postural muscles are fixators

8. Types of Movements

9. Common movement of a hinge joint
Flexion and Extension
Flexion = movement which decreases the angle of the joint; brings two bones closer together
Extension = movement which increases the angle of the joint or the distance between two bones
Hyperextension = extension greater than 180o
Common movement of a hinge joint

10. Flexion and Extension

11. Flexion and Extension

12. Flexion and Extension

13. Rotation
Rotation = movement of a bone around its longitudinal axis

14. Abduction and Adduction
Abduction = moving away from midline
Adduction = moving toward midline

15. Circumduction
Circumduction = combination of flexion, extension, abduction and adduction
Proximal end of the joint is stationary
Distal end moves in a circle

16. Dorsiflexion and plantar flexion
Dorsiflexion = lifting the foot at the ankle towards the shin
Standing on your heels
Plantar flexion = depressing the foot
Pointing your toes

17. Inversion and Eversion
Special movements of the foot
Inversion = turning the sole of the foot medially
Eversion = turning the sole of the foot laterally

18. Supination and Pronation
Refer to movements of the radius around the ulna
Supination = turning backward
Palm facing backward; radius and ulna cross
Pronation = turning forward
Palm facing forward; radius and ulna are parallel

19. Opposition Specifically of the thumb
Ability to touch your thumb to your fingertip

20. Protraction and Retraction
Protraction: moving a body part anteriorly in the horizontal plane
Ex: grasp you upper lip with your lower teeth
Retraction: moving a body part posteriorly in the horizontal plane

21. Naming Skeletal Muscles

22. Direction of muscle fibers
Rectus = straight; fibers run parallel to an imaginary line, usually midline
Ex: rectus femoris = straight muscle of the thigh
Oblique = muscle fibers run at a slant to an imaginary line

23. Terms related to size Maximus = large Minimus = small Longus = long
Ex: gluteus maximus = largest muscle of the gluteus group
Minimus = small
Longus = long

24. Terms related to location
Some muscles are named for the bone with which they are associated
Ex: temporalis overlays the temporal bone

25. Terms related to number of origins
Biceps = two origins
Tripceps = three origins
Quadriceps = 4 origins

26. Terms related to location of origin and insertion
Ex: sternocleidomastoid muscle has its origin on the sternum (sterno) and clicel (cleido) and inserts on the mastoid process of the remporal bone

27. Terms related to shape of muscle fibers
Deltoid = triangular
Orbicularis
Pectinate
Piriformis
Platy
Pyramidal
Rhomboid
Serratus
Splenius
Teres
Trapezius
Pennate
Digastric
Fusiform

28. Other muscle terminology
Alba
Brevis
Gracilis
Lata
Latissimus
Longus
Magnus
Minor
Vastus
Tendinosus
longissimus

29. Terms related to muscle action
Flexor, extensor, adductor
Ex: extensor muscles of the wrist extend the wrist.