1. The Muscular System
Support Systems
Unit 2

2. Vocabulary- combining forms
Cardi/o heart
Fasci/o fascia, connective tissue
Fibr/o fiber, fibrous tissue
Leiomy/o smooth muscle
Muscul/o muscle
My/o muscle
Ten/o, tend/o, tendin/o tendon

3. Vocabulary- prefixes A- or an- without or not Ab- away Ad- towards
Bi- two
Hemi- half
Hyper- excessive, above normal
Intra- between
Quadri- four
Tri- three

4. Vocabulary- suffixes -algia pain -ar pertaining to -ceps heads
-cyte cell
-duction act of leading
-genesis production of
-itis inflammation
-oma tumor
-osis abnormal condition
-pathy disease
-plasty surgical repair
-plegia paralysis
-rrhaphy sutures
-rrhexis rupture
-tome instrument to cut
-tomy incision
-trophy development, nourishment
-um structure, thing

5. Vocabulary- abbreviations and terms
MRI magnetic resonance imaging
Antagonist the muscle that does the opposite motion
Agonist prime mover, the muscle that does most of the work
Insertion the distal attachment/ the moving end
Involuntary does not need conscious thought
Origin the proximal attachment/ the stable end
Striations striped
Synergist helper muscle
Thermogenesis heat production
Voluntary needs conscious thought

6. Functions of the Muscular System
Heat Production (thermogenesis)
Heat is a byproduct of muscle contraction
Movement Facilitation
Muscles shorten and pull on bones which produces movement
Structure (postural support)
Contraction of muscles keeps us upright and maintains posture

7. Functions cont. Protection of Internal Organs
Contraction of abdominal muscles causes them to become hard and offers protection to the underlying organs
Other muscles can contract prior to receiving a blow thus protection bones and soft tissue.
Controls the volume of hollow organs
Smooth muscle surrounds our hollow organs and contractions propel the substances through them, aid in their emptying, or helps control their volume
Stomach and small intestines
The bladder
Blood vessels

8. Types of Contractibility
Voluntary- contractions controlled by conscious thought or will
Involuntary- contract due to unconscious impulses sent by the autonomic nervous system or certain specialized cells or hormones

9. Muscle Appearance
Striated- stripes, muscles that on a microscopic level have cross fiber stripes
Non-striated- Not having stripes, muscles cells that microscopically have a smooth appearance

10. Cardiac Muscle Forms the bulk of heart wall (Myocardium) Striated
Involuntary (typically)
Cardiac fibers typically have a centrally located nucleus
Intercalated discs
Strengthens cardiac muscle tissue
Allows for special wringing muscle contraction

11. Smooth Muscle Located in walls of hollow internal surfaces such as:
blood vessels - stomach
urinary bladder - intestines
Non-striated in appearance
Involuntary (typically)
Contractions usually move things along, from point A to point B (peristalsis)

12. Skeletal Muscle Attached to bones
Striated appearance under a microscope
Voluntary control (conscious control)
Allow for postural support and movement of body parts, both axial and appendicular

13. Skeletal Muscle Tissue

15. Tendons Connect muscle to bone
Made of dense fibrous connective tissue that surrounds the muscle belly and extends further, becoming tendon

16. Muscle Actions
Agonist- the prime mover, or the muscle that does the most work
Antagonist- the muscle that does the opposite motion
Fixator- holds the body part in place while the action takes place
Synergist- the helper muscle, assists in making the motion happen

17. Motions
Peristalsis- a wave like motion by smooth muscle to advance substances
Abduction- movement away from midline
Adduction- movement towards midline
Flexion- decreasing a joint angle
Extension- increasing a joint angle
Hyperextension- extension past normal extension, or past anatomical position

18. Motions Plantarflexion- specific to ankle motion, pointing the toes
Dorsiflexion- specific to ankle motion, pulling the toes towards the shin
Supination- turning palm up
Pronation- turning palm down
Rotation- movement around an axis
Circumduction- cone shaped motion

19. Origin vs. Insertion
Origin- the most proximal end of the muscle, the non moving end, or where the muscle starts
Insertion- the distal end of a muscle, the moving end, or where the muscle goes to

20. Location and Function of Skeletal Muscles
Biceps Brachii
Origin: anterior shoulder
Insertion: anterior elbow
Action: elbow flexion
Triceps Brachii
Origin: posterior shoulder
Insertion: posterior elbow
Action: elbow extension

21. Location and Function of Skeletal Muscles
Trapezius
Origin: cervical and thoracic spine
Insertion: spine of the scapula
Action: extends or hyperextends the head and neck, (also helps with shoulder retraction and elevation and depression)
Latissimus Dorsi
Origin: Lower thoracic and lumbar spine as well as the pelvis
Insertion: proximal humerus
Action: extends a flexed arm or hyperextends the arm from the anatomical position

22. Location and Function of Skeletal Muscles
Deltoid
Origin: clavicle and spine of the scapula
Insertion: lateral humerus
Action: shoulder abduction
Pectoralis Major
Origin: upper ribs along the sternum and clavicle
Insertion: humerus
Action: adduction

23. Location and Function of Skeletal Muscles
Rectus Abdominis
Origin: anterior lower ribs
Insertion: pubic bones
Action: lumbar spine flexion
Diaphragm
Origin: central tendon (fibrous tissue)
Insertion: circumference of lower rib cage
Action: expands chest for breathing

24. Location and Function of Skeletal Muscles
Quadriceps (group of 4 muscles)
Origin: anterior pelvis and proximal femur
Insertion: anterior tibia
Action: knee extension
Hamstrings (group of 3 muscles)
Origin: ischium and posterior femur
Insertion: posterior tibia and fibula
Action: knee flexion

25. Location and Function of Skeletal Muscles
Gluteus Maximus
Origin: ilium, sacrum, and coccyx
Insertion: femur
Action: extends hip
Gastrocnemius
Origin: femur
Insertion: calcaneus (heel bone)
Action: plantar flexes ankle (when knee is straight)
Soleus
Origin: tibia and fibula
Action: plantar flexes ankle (when knee is bent)

26. Anterior Skeletal Muscles

27. Posterior Skeletal Muscles

28. Diseases and Disorders of the Muscular System

29. Tendonitis
Tendonitis is characterized by Inflammation of the tendons due to overuse or age-related changes of the tendon.
It is common in individuals who begin a new exercise or increase their level of exercise.
Age-related tendonitis is due to the loss of elasticity and the ability of the tendon to glide smoothly.
Treatment includes: rest, ice, compression, and elevation (RICE).

30. Strains A tearing of a muscle or its attaching tendon
Occurs when a muscle receives a stress that overcomes its strength
Sudden, quick heavy lifting
During sports
While performing work tasks

31. Strains cont. 3 types of strains Signs and symptoms Treatment
1st degree occurs when the muscle is stretched causing micro-tears in the muscle fibers
2nd degree sprain occurs when the muscle or tendon is partially torn
3rd degree sprain occurs when the muscle is completely ruptured
Signs and symptoms
Pain, especially when the muscle is contracting which limits function, swelling, and bruising
Treatment
Rest, Ice, Compression, Elevation (RICE)

32. Muscle Spasm An involuntary muscle contraction
Also called a “Charlie Horse” or “muscle cramp”
Main causes are electrolyte imbalances, dehydration and fatigue

33. Muscle Spasm cont.
Initial treatment is to put the muscle that has the spasm on stretch
If spasm persists ice or heat can be used
Prevention incudes maintaining a proper diet, drinking plenty of water and proper conditioning
Sports drinks may be beneficial during exercise to help replace lost sodium due to sweating

34. Muscular Dystrophy
An inherited disorder in which the muscles are missing a certain protein causing degeneration of muscle tissue
Causes progressive weakness and loss of function of the affected muscles
There is no cure but physical therapy can lessen the severity of the disorder.