1. The Muscular System The ability to move is an essential activity of the human body The ability to move is an essential activity of the human body ½ our body weight comes from muscles ½ our body weight comes from muscles Consists of over 600 individual muscles. Consists of over 600 individual muscles. 3 purposes: 3 purposes: –Body movement –Body shape –Body heat (maintain temp.)

2. The Muscular System Body movements are determined by three types of muscles Body movements are determined by three types of muscles –Smooth (involuntary) – cannot be controlled by will. –Cardiac – control the contractions of the heart. –Skeletal (Voluntary) – can be controlled by will.

3. Function of Skeletal muscles Attach to bones to provide voluntary movement Attach to bones to provide voluntary movement –Tendons: strong, tough connective cords –Fascia: tough, sheet-like membrane Produce heat and energy for the body Produce heat and energy for the body Help maintain posture Help maintain posture Protect internal organs Protect internal organs Called striated (striped) because they have striations of alternating light and dark band Called striated (striped) because they have striations of alternating light and dark band Multi-nucleated Multi-nucleated

4. Functions cont’d. Fleshy body parts are made of skeletal muscles Fleshy body parts are made of skeletal muscles Provide movements to the limbs, but contract quickly, fatigue easily and lack the ability to maintain contraction for long periods Provide movements to the limbs, but contract quickly, fatigue easily and lack the ability to maintain contraction for long periods –Blinking eyes, talking, breathing, eating, dancing and writing all produced by these muscles

7. Function of Smooth Muscle Called smooth muscle because they are unmarked by striations, small spindle shaped and uninucleated Called smooth muscle because they are unmarked by striations, small spindle shaped and uninucleated Unattached to bones, act slowly, do not tire easily and can remain contracted for a long time Unattached to bones, act slowly, do not tire easily and can remain contracted for a long time Not under conscious control so they are also called involuntary muscles Not under conscious control so they are also called involuntary muscles Found in walls of internal organs (intestines, bladder, stomach, uterus, blood vessels) Found in walls of internal organs (intestines, bladder, stomach, uterus, blood vessels)

9. Function of cardiac muscle Found only in the heart Found only in the heart Involuntary muscle Involuntary muscle Requires a continuous supply of oxygen to function Requires a continuous supply of oxygen to function Cardiac muscle cells begin to die after 30 seconds of oxygen cut-off Cardiac muscle cells begin to die after 30 seconds of oxygen cut-off Striated and branched; uninucleated Striated and branched; uninucleated

11. Special muscles Sphincter (dilator) muscles are openings between Sphincter (dilator) muscles are openings between –the esophagus and stomach –The stomach and small intestines –Walls of the anus, urethra and mouth Open and close to control passage of substances Open and close to control passage of substances

12. Characteristics of Muscles All muscles have 4 common characteristics All muscles have 4 common characteristics –Excitability – ability to respond to a stimulus (ie: nerve impulse) –Contractibility – muscle fibers that are stimulated by nerves contract (become shorter) and causes movement –Extensibility – ability to be stretched –Elasticity – allows the muscle to return to its original shape after it has been stretched

13. Sources of heat/energy When muscles work, they produce heat that our body needs to function properly When muscles work, they produce heat that our body needs to function properly Major source of this energy is ATP – a compound found in muscle cells Major source of this energy is ATP – a compound found in muscle cells ATP requires muscle cells to have oxygen, glucose and other materials circulated by the blood ATP requires muscle cells to have oxygen, glucose and other materials circulated by the blood When the muscle is stimulated, ATP is released, thus producing heat When the muscle is stimulated, ATP is released, thus producing heat

14. Types of Body Movements Adduction: Adduction: –Moving a body part toward the midline Abduction: Abduction: –Moving a body part away from the midline Flexion: Flexion: –Decreasing the angle between two bones or bending body parts Extention: Extention: –Increasing the angle between two bones or straightening the body part Rotation: Rotation: –Turning a body part around its own axis Circumduction: Circumduction: –Moving in a circle at a joint

15. Buildup of lactic acid caused by vigorous exercise where blood is unable to be transported: Buildup of lactic acid caused by vigorous exercise where blood is unable to be transported: –MUSCLE FATIGUE State of partial contraction is called: State of partial contraction is called: –MUSCLE TONE Loss of muscle tone occurs when muscles are not used for a long period of time. Muscles atrophy (shrink in size and lose strength) and results in: Loss of muscle tone occurs when muscles are not used for a long period of time. Muscles atrophy (shrink in size and lose strength) and results in: –CONTRACTURES  Foot drop is the most common type of contracture seen, but fingers, knees and other joints can be affected

16. MUSCLES YOU NEED TO KNOW THE FUNCTIONS OF: Biceps – flexes lower arm Biceps – flexes lower arm Deltoid – abducts arm; injection site Deltoid – abducts arm; injection site Sternocleidomastoid – turns head Sternocleidomastoid – turns head Gastrocnemius – flexes sole of feet Gastrocnemius – flexes sole of feet Latissimus dorsi – extends & adducts upper arm Latissimus dorsi – extends & adducts upper arm Pectoralis major – adducts and flexes upper arm Pectoralis major – adducts and flexes upper arm intercostals – moves ribs for breathing intercostals – moves ribs for breathing

17. Trapezius – extends head, moves shoulder Trapezius – extends head, moves shoulder Triceps – extends lower arm Triceps – extends lower arm Gluteus maximus – extends thigh; injection site Gluteus maximus – extends thigh; injection site Sartorius – abducts thigh, flexes leg Sartorius – abducts thigh, flexes leg Vastus lateralis – extends leg Vastus lateralis – extends leg Rectus abdominus – compresses the abdomen Rectus abdominus – compresses the abdomen Rectus femoris – flexes thigh & extends lower leg Rectus femoris – flexes thigh & extends lower leg Tibialis anterior – flexes and inverts foot Tibialis anterior – flexes and inverts foot

18. FIBROMYALGIA FIBROMYALGIA Chronic, widespread pain in specific muscle site; numbness and tingling in arms or legs; headaches Chronic, widespread pain in specific muscle site; numbness and tingling in arms or legs; headaches Cause unknown Cause unknown Treat symptoms – pain relief; stress reduction and muscle relaxers Treat symptoms – pain relief; stress reduction and muscle relaxers MUSCULAR DYSTROPHY MUSCULAR DYSTROPHY Group of inherited diseases that cause chronic, progressive muscle atrophy resulting in total disability and early death Group of inherited diseases that cause chronic, progressive muscle atrophy resulting in total disability and early death No cure No cure Treatment used to slow progression of disease Treatment used to slow progression of disease

19. MYASTENIA GRAVIS MYASTENIA GRAVIS Chronic condition where nerve impulses are not transmitted correctly leading to progressive muscular weakness and paralysis; affects respiratory muscles and can be fatal Chronic condition where nerve impulses are not transmitted correctly leading to progressive muscular weakness and paralysis; affects respiratory muscles and can be fatal Cause unknown Cause unknown Treatment is supportive Treatment is supportive MUSCLE SPASMS/CRAMPS MUSCLE SPASMS/CRAMPS Sudden, painful involuntary muscle contractions Sudden, painful involuntary muscle contractions Caused from overexertion, low electrolytes or poor circulation Caused from overexertion, low electrolytes or poor circulation Treat by applying gentle pressure and stretching of the affected muscle Treat by applying gentle pressure and stretching of the affected muscle

20. STRAIN STRAIN Overstretching of a muscle or tendon frequently in legs, back or arms Overstretching of a muscle or tendon frequently in legs, back or arms Caused by sudden muscle exertion Caused by sudden muscle exertion Treated by resting, muscle relaxants, or pain medications, elevation of extremity and applying hot/cold compresses Treated by resting, muscle relaxants, or pain medications, elevation of extremity and applying hot/cold compresses

21. RANGE OF MOTION

22. ????? WHY ????? Done to maintain health of the musculoskeletal system (muscle/skeleton) Done to maintain health of the musculoskeletal system (muscle/skeleton) Each joint and muscle is moved through its full range for patients with limited ability to move Each joint and muscle is moved through its full range for patients with limited ability to move Administered by: PT, RN, Assistant, or other authorized personnel (with training) Administered by: PT, RN, Assistant, or other authorized personnel (with training) Done to prevent problems caused by lack of movement Done to prevent problems caused by lack of movement

23. Problems from lack of movement Contractures Contractures –Tightening and shortening of a muscle resulting in a permanent flexing of a joint Muscle atrophy Muscle atrophy –Muscles become weak and joints become stiff Circulatory impairment Circulatory impairment –Blood clots and pressure ulcers can develop Mineral loss Mineral loss –Especially calcium from the bones making bones brittle and easily to be fractured Other problems Other problems –Poor appetite; constipation; urinary infections; respiratory problems; and pneumonia