1. Diseases and Disorders
Muscular System
Diseases and Disorders

2. Muscular Dystrophy
Group of diseases that cause progressive weakness and loss of muscle mass
Duchenne Muscular Dystrophy
Becker Muscular Dystrophy
Abnormal genes (mutations) interfere with the production of proteins needed to form healthy muscle
Primarily in boys
No cure
Signs and symptoms typically appear between the ages of 2 and 3
Frequent falls
Difficulty getting up from a lying or sitting position
Trouble running and jumping
Waddling gait
Walking on the toes
Large calf muscles
Muscle pain and stiffness
Learning disabilities

3. Muscular Injury

4. Injury: Muscle Strain Stretching or tearing of muscle or tendon
An acute strain occurs when a muscle becomes strained — or may even tear — when it stretches unusually far or abruptly
A chronic strain results from prolonged, repetitive movement of a muscle

5. Injury: Muscle Cramps
Sudden and involuntary contraction of one or more of your muscles
Causes
Inadequate blood supply
Nerve compression
Dehydration

6. Muscle Infections
Caused by bacteria, viruses, and parasites that infect muscle tissue
Produces myositis (local or widespread)
Examples:
Influenza (muscle stiffness and pain)
Trichinosis (muscle pain and fatigue)
Thread worm

7. Infection: Poliomyelitis
Polio is a contagious viral illness that in its most severe form causes paralysis, difficulty breathing and death
In the U.S., the last case of naturally occurring polio happened in 1979
Poliovirus resides only in humans and enters the environment in the feces of someone who's infected Poliovirus spreads primarily through the fecal-oral route
Transmitted through contaminated water and food or through direct contact with someone infected

8. Myasthenia Gravis
Characterized by weakness and rapid fatigue of any of the muscles under your voluntary control
Caused by a breakdown in the normal communication between nerves and muscles
No cure for myasthenia gravis, but treatment can help relieve signs and symptoms
S/s:
Weakness of arm or leg muscles, double vision, drooping eyelids, and difficulties with speech, chewing, swallowing and breathing

9. Heart Disease (Muscle)
Heart disease describes a range of conditions that affect your heart
Coronary artery disease
Arrhythmias
Congenital heart defects
Used interchangeably with the term "cardiovascular disease.”
Refers to conditions that involve narrowed or blocked blood vessels that can lead to a heart attack, chest pain (angina) or stroke

10. Heart: Hypertrophic Cardiomyopathy
Disease in which the myocardium becomes abnormally hypertrophied
Usually caused by abnormal genes (gene mutations)
Usually inherited
Thickened heart muscle can make it harder for the heart to pump blood
Often goes undiagnosed because many people with the disease have few, if any, symptoms
S/S:
Death if activity is too strenuous
Shortness of breath
Chest pain
Problems in the heart's electrical system
Arrhythmias