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The muscles move the body like strings move a puppet.
The muscular system is made up of… muscles and tendons The prefixes “my/o” and “sarc/o” refer to muscles.
The Muscular System l Muscle is a general term for contractile tissue l 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.
l 5 Muscles produce movement by shortening in length or contracting. Copyright © The Mc. Graw-Hill Companies, Inc. Chapter 6
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 l l l 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 l l 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: l maintain posture l protect internal organs l stabilize joints l produce movement l 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.
Naming Muscles l – 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 – – – 11 Copyright © The Mc. Graw-Hill Companies, Inc. Chapter 6
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 l l l 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.
l l Extension means to straighten a joint. The joint angle increases. An Extensor muscle straightens the joint
Abduction *movement in the frontal plane l Means to move or take away from the body, usually midline
Adduction l *movement in the frontal plane Means to add or move toward the body
Pronation and Supination l l l 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 l Combined flexion, extension, abduction and adduction
Rotation l Means to rotate or move around an axis. For example, you turn your head side to say no.
Dorsiflexion/Plantarflexion l Flexion and extension at the ankle joint
Did you know? ? ? It takes more muscles to frown than to smile?
l 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
Fibromyalgia – a chronic pain in muscles. – – – 23 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 months Pain in at least 11 of 18 tender-point sites. Treatment includes pain medication physical therapy, massage and muscle relaxants Copyright © The Mc. Graw-Hill Companies, Inc. Chapter 6
Bursitis and Tendonitis 24 l Bursitis– an inflammation of the bursa surrounding a joint. l Tendonitis – an inflammation of a tendon in a joint caused by overwork. Copyright © The Mc. Graw-Hill Companies, Inc. Chapter 6
– Dislocation – may result from an injury or strenuous, sudden movement.
Muscular dystrophy – a group of inherited diseases that cause progressive weakness and disability