The muscles move the body like strings move a puppet.

The muscular system is made up of…

muscles

and

tendonsThe prefixes “my/o” and “sarc/o” refer to

muscles.

The Muscular System

Muscle is a general term for contractile tissue

Consists of over 600 individual muscles.

What are muscles made of?

Stretchy, elastic

cells and fibers

All muscle cells are elongated and are called fibers.

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Muscles produce movement by shortening in length or contracting.

Chapter 65

Three types of muscles

Involuntary or Smooth – cannot be controlled by will.

Cardiac – controls the contractions of the heart. (involutary)

Voluntary or Skeletal – can be controlled by will.

Smooth Muscle

Smooth muscles are found in the hollow parts of the body. This would be in places like the stomach, intestines, blood vessels and the bladder

they are usually in sheets, or layers, with one layer of muscle behind the other.

Because it is the muscle of organs, it is sometimes called visceral muscle

Cardiac Muscle

Cardiac muscles are involuntary and found only in the heart.

Most of your heart is made of cardiac muscle. The cardiac muscle never stops working until you die.

Voluntary or Skeletal Muscles(also called Striated because the muscles

appear to be striped)– Function is to:

maintain posture protect internal organs stabilize jointsproduce movement produce heat and energy for the

body

Most muscles span across joints attach to bones in at least two places.

1. The bone that moves when a muscle contracts is called the muscle's insertion.

2. The bone that does not move, or is less moveable, is called the muscle's origin.

3. The motion produced by the contraction is called the muscle's action.

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Naming Muscles– Muscles can be named based on any of the

following criteria:

– Muscle location (biceps brachii, brachii = arm)– Number of origins (biceps brachii has two origins

bicep=two heads)– Action (adductor longus, adducts the thigh)– Size (gluteus maximus, maxiumus=biggest)– Location of attachments– Shape (deltoid, delta=triangle)– Combination of all the above

Chapter 611

Why do I need tendons?

Tendons attach my muscles to my bone helping my body move.

Feel your tendon right above your heel in the back of your leg.

This is the thickest tendon in your body.

Muscle Movements Flexion – the act of bending. The joint angle

decreases. The muscle that bends the joint is called flexor

muscle When you bend your elbow your are flexing.

Extension means to straighten a joint. The joint angle increases.

An Extensor muscle straightens the joint

Abduction *movement in the frontal plane

Means to move or take away from the body, usually midline

Adduction

Means to add or move toward the body

*movement in the frontal plane

Pronation and Supination

Special movements of the forearm Pronation is palms down Supination is palms up (facing forward if in the

anatomical position)

Circumduction – to make a circle

Combined flexion, extension, abduction and adduction

Rotation

Means to rotate or move around an axis. For example, you turn your head side to side to say no.

Dorsiflexion/Plantarflexion

Flexion and extension at the ankle joint

Did you know?????

It takes more muscles to

frown

than to

smile?

Diseases and Disorders– Strain – overuse of a muscle and/or

tendon.– Strains cause pain, swelling and limited

movement.– Strains should be treated immediately with:

– Rest– Ice– Compression – Elevation

RICE

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Fibromyalgia

– a chronic pain in muscles. The term "fibromyalgia" means pain in the

muscles, ligaments and tendons. – Symptoms include:– A history of widespread pain (pain on both sides of

the body and above and below the waist) that is present for at least three monthsPain in at least 11 of 18 tender-point sites.

– Treatment includes pain medication physical therapy, massage and muscle relaxants

Chapter 623

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Bursitis and Tendonitis

Chapter 624

– Dislocation – may result from an injury or strenuous, sudden movement.

Muscular dystrophy – a group of inherited diseases that cause progressive weakness and disability