Muscular System

Major Structures

1. Muscles- my/o. These make the body movement possible, hold body erect, move body fluids, and produce body heat.

2. Fascia- Fasci/o, cover, support, and separate muscles.

3. Tendons- ten/o, tend/o, tendin/o. Attach muscles to bone.

4. Aponeurosis- is a flat fibrous sheet of connective tissue that is similar to a tendon. It attaches muscle to bone or to other tissues.

Functions of Muscle

1. Muscles hold the body erect and make movement possible.

2. Muscle movement generates nearly 85 % of the heat that keeps us warm.

3. Muscles move food through the digestive system.

4. Muscle movement, such as walking, aids the flow of blood through veins as it returns to the heart.

5. Muscle action moves fluids through the ducts and tubes associated with other body systems.

Types of muscle tissue

1. Skeletal muscles- attach to the bones of the skeleton and are the muscles that make possible body motions such as walking and smiling.

a. they are know as striated muscles because the dark and light bands in muscles fibers create a striped appearance.

b. they are also know as voluntary muscles because we have control over them.

2. Smooth Muscles- are located in the walls of internal organs such as our digestive tract, blood vessels, ect.

a. they are know as Unstriated muscles because they do not have the dark and light bands that produce striated appearance.

b. These muscles are know as involuntary muscles because they are under control by our nervous system.

c. Smooth muscles are also know as visceral muscles because they are found in the large organs and in hollow structures such as

those of the digestive and urinary systems.

3. Cardiac Muscles- also known as the myocardial muscle. Forms the wall of the heart. My/o means muscle and cardi means heart.

a. Cardiac muscle is a specialized tissue that is like striated muscle in appearance but like smooth muscle in its action. This muscle causes the heart to beat and keep us alive.

Characteristics of Muscles

1. Muscles are arranged in antagonistic pairs, meaning they work in opposition to each other. Ex. Bicep vs. tricep because they move elbow joint in opposite directions.

2. Contraction- is the tightening of a muscle. As the muscle contracts it becomes shorter and thicker, causing the belly (center) of the muscle to enlarge.

3. Relaxation- occurs when a muscle returns to its original form. Once a muscle relaxes it becomes longer and thinner. When one muscles pair contracts, the other usually relaxes.

4. Muscle tone- also known as Tonus, Is the normal state of balanced muscle tension that is required to hold the body in an awake position.

How Muscles are Named

• 1. Muscle Origin and Insertion- origin is where muscle begins and insertion is where it ends.

• Ex. Sternocleidomastoid.

• 2. Muscle named by their action- ex. Flexor carpi and Extensor Carpi muscles

• 3. Muscles named for their location- ex. Pectoralis major

• 4. Fiber direction- ex. Rectus abdominis, rectus- means straight and abdominal means abdomen.

• 5. By number of division- ex. Biceps brachii, triceps brachii

• 6. Named for their size- gluteus maximus, means big butt :) or biggest muscle of the buttocks

• 7. Named by shape- ex. Deltoid muscle is shaped like an inverted triangle or the Greek letter delta

Activity

1. *Answer these two questions about Duchenne's and Becker's Muscular Dystrophy. question:

1. What is the disease and how does it affect the body? Please tell me how if physically and mentally effects the body.

2. How do you think this disease would effect the family involved.

Movements

• ROM- Range of Motion • Abduction- movement away from the mid-line.

Example is an abductor longus in your leg.• Adduction- movement towards your mid-line. • Flexion- means to decrease the angle between

two bones that make up the joint.• Extension- to increase the angle between two

bones at a joint. • Hyperextension- an extreme of overextension

of a limb at a joint.

• Elevation- raising or lifting a body part, ribs raise during breathing.

• Depression- act of lowering a body part, ribs when we exhale.

• Rotation- circular movement around an axis . • Supination- rotating arm so palm of hand is in

anatomical position. • Pronation- rotating forearm to where palm is

facing down. • Dorsiflexion- pulling toes towards head. • Plantar flexion- calf raise, moving foot down

Medical professionals that specialize in muscles.

1- Orthopedic Surgeon- treats injuries and disorders involving bones, joints, muscles, and tendons.

2- Rheumatologist- Treats disorders that involve the inflammation of connective tissue including muscles.

3- Neurologist- treats the cause of paralysis and similar muscular disorders in which there is a loss of function.

4- Sports Medicine Specialist- treats sports related injuries of the bones, joints, and muscles.

Pathology

• Fascitis- • Tenalgia- • Tendonitis- • Adhesion- is a band of fibrous tissue that holds

structures together abnormally. • Muscle Atrophy- weakness and wasting away of muscle

tissue. Usually after being casted or in a brace for a long period of time.

• Myalgia- • Myolysis- degeneration (break down) of muscle tissue.

My means muscle and lysis means destruction or breaking down

• Polymyositis- is a chronic, progressive disease affecting the skeletal muscles.

• Myomalacia-

• Myorrhexis-

• Myosclerosis-

• Hernia- is a protrusion of a part or structure through the tissues normally containing it.

• Myocele- is the protrusion of a muscle through its ruptured sheath or fascia.

Activity

• Internet Search these two Muscular disorders.

1- Rotator Cuff injuries- Find three different ones and tell me how they are fixed?

2- Carpal Tunnel Syndrome- Tell me what the definition is and how it is fixed?

Career Opportunities

1. Orthopedic Surgeon2. Rheumatologist3. Neurologist4. Licensed Athletic Trainer5. Chiropractor6. Physical Therapist7. Physical Therapy Assistant8. Massage therapist9. Kinesiotherapist10. Occupational Therapist11. Occupational Therapist Assistant

Assignment1. Pick five careers that interest you.

2. Go to texashotjobs.org

3. Find the following information below for your five jobs.

• Tell me three schools that I can attend to obtain this degree

• How many years will it take to obtain this degree?

• What does this license allow you to do? • How much money can this profession make?

Pathology of Muscle

Starts with Hernia on page 70 and ends with cardioplegia on page 75.