1. Medical Terminology I Muscular System
Chapter 15

2. Functions
Types of Muscles
Structures
Types

3. Functions
Movement
Create Heat
Provide support

4. Types of Muscles Skeletal Muscle- called Striated voluntary muscles
Cardiac Muscle- called mixed it contains both voluntary and involuntary muscle fiber
Nonstriated Muscles- called involuntary muscles or smooth muscles found in the intestines, blood vessels

5. New York, 1837. Chromolithograph. National Library of Medicine.
Jean Baptiste Sarlandière( )[author]J. Bisbee[artist]

6. Structure Contractile cells- made up of myofilaments
Myosin protein that makes up the filaments
Sarcomere- basic contractile unit seperated by “Z” lines
Thick and thin filaments slide past each other and catch like “barbs” of a thistle

7. Muscle Tissue
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8. Contraction
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9. Structure Continued…
All or none principle- the fibers must contract completely when they are stimulated

10. Structure
Origin point immobile point where it attaches to bone tendon that attaches muscle to bone.
Body of the muscle (belly) greatest amount of contractile fibers are found
Insertion- muscle attaches to the bone and creates joint movement

11. Muscle Actions
Prime Movers- muscle that creates the greatest amount of movement….most muscle action is carried out by groups of muscles
Synergist- muscles that help the prime movers move the body
Antagonistic- muscles that move opposite of the prime movers

12. Muscle Actions
Tonic Contractions- muscles that stay contracted to provide good posture
Can be trained to improve posture
Sit up straight
Stand up straight
Maintain muscle control through contractile exercises
Crunches and pelvic floor exercises
Poor posture causes problems with your back and disease…..

13. Muscle Fatigue Muscles have built in energy called glycogen
The more you exercise the more glycogen you store increases endurance slows the fatigue process
When you burn Glycogen you release acid into muscles (lactic acid)
To remove lactic acid you need to exercise more

14. Motor Unit
Motor neurons are specialized nerve cells that stimulate muscles to shorten and produce movement
Motor units are nerve/ muscle connects
Different types of motor units require different levels of stimulation to cause contraction

15. Fast Twitch
All people have both fast and slow twitch muscle fibers…..sprinters have more fast twitch muscle fiber and fewer slow twitch tissues
Isotonic contractions- muscle contractions that produce movement
Isometric contractions- muscle contractions that do not produce movement muscle tension increases.

16. Exercise and Muscles
Exercise is essential for proper muscle growth and motor development
Atrophy- muscles become smaller due to lack of use or disease
Hypertrophy- increase in muscle size due to exercise

17. Muscle movements
Flexion
Extension

18. Muscle movements
Abduction
Adduction
Rotation

19. Muscle movements
Supination
Pronation

20. Muscle movements
Dorsiflexion
Plantar Flexion

21. Muscular Disorders Injuries
Strain- overexertion or trauma to muscles causing over stretching or tearing of muscle fiber
Cramps- painful contraction of muscle fiber

22. Muscular Disorders
Poliomyelitis- a viral infection of the motor neurons causes paralysis
Muscular Dystrophy- rapid progressive weakness and atrophy of muscles

23. Activities
Vocabulary Flashcards

24. Assessment 15.06
Give the word for each definition, break it down into its parts, and give an example of a medical term using it.
Sheaths enveloping muscles
Muscle
Soles of the feet
Lack of strength
Back
Smooth muscle lining the intestinal tract
Development, nourishment
Toward
Away from
Skeletal muscle connected to bone

25. Assessment 15.07 – Case Study
Clinical information:
The patient was a 48 year-old woman who presented with a 10 cm proximal, anterior intramuscular mass in her left thigh. Magnetic resonance imaging (MRI) studies suggested a "fatty tumor".  The patient was prepped for sugery and the mass was sent to the pathology department for evaluation and diagnosis. A resection yielded the following specimen.
Gross pathology of the case:
The tumor was a soft mass and the surface was covered by some tan tissue fragments that were grossly consistent with skeletal muscle. The cut surface was translucent and gelatinous. Neither necrosis nor hemorrhage was present.
Cellular myxoma, also known as low-grade myxoid neoplasm with recurrent potential, is a term that has been used recently to describe a family of myxomatous neoplasm with features in between intramuscular myxoma and low-grade myxofibrosarcoma. Although these tumors may recur, they do not metastasize. During the short available period of follow up in two of the recent studies, the rate of recurrence of these tumors is low.
Mirela Stancu, M.D.1 and Kar-Ming Fung, M.D., Ph.D.2 Last update on July 30, 2003.
1 Department of Pathology, Roger William Medical Center-University Medical Group, Providence, Rode Island and 2 Department of Pathology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma.