Muscular System

Functions Movement-muscles can contract (shorten) and extend Generate heat through movement Muscular system moves food, blood and other fluids through their respective body systems

Structures of the muscular system Muscles - Fascia Structures of the muscular system 1. Muscle fibers- cells that make up muscles 2. Fascia-band of connective tissue that covers & supports the muscle. 3. Tendons- connective tissue that attach muscle to bone ex: Achilles tendon- attached gastrocnemius to calcaneus.

Types of Muscle Tissue 1. Skeletal – attached to bones; voluntary & striated 2. Smooth-internal organd; involuntary, unstriated, visceral (pertaining to internal organs) 3. myocardial- muscle of heart; involuntary & striated

Movement of muscles Movement of muscles made possible by two points of attachment: origin & insertion Origin: located on a stationary bone; where muscle begins Insertion: located on a moveable bone

Muscles – Origin or Insertion Lift up your right forearm to flex your bicep brachii as if making a fist. Identify the origin and insertion attachment by agreeing with one of the following statements: The radius is the origin and the scapula is the insertion. ---OR--- The scapula is the origin and the radius is the insertion.

Pathology-Abnormal Muscle Tone Muscle tone = tonus Hypertrophy: abnormal increase in muscle size Atrophy: muscles shrink in size from disuse

Pathology-Abnormal Muscle Tone Spasms: abnormal contractions Rigor: abnormal muscle stiffness Tetany: painfully long spasm

Muscular Dystrophy Genetic disorder Progressive disease of muscle weakness and degeneration of skeletal muscles Duchenne muscular dystrophy (DMD) most common; boys age 3-5; unable to walk by age 12; need a respirator to breathe later in life.

Myasthenia Gravis Autoimmune disorder that affects neuromuscular junctions Weakness of voluntary muscles

Treatments for Muscular disorders RICE for 1st aid- Rest, Ice, Compression, Elevation Occupational or physical therapy Medications Antispasmoic to relax smooth muscles Neuromuscular blocker-causes temporary paralysis (used with anesthesia) Skeletal muscle relaxant-relieve stiffness, pain, and discomfort.

Vocabulary List-Unit 4 muscul/o, my/o, myos/o Fasci/o Ten/o, tend/o, tendin/o Ton Kines asthenia