The Muscular System Chapter 4

Objectives Describe the functions and structures of the muscular system including muscle fibers, fascia, tendons and the three types of muscle Recognize, define, spell and pronounce the terms related to muscle movements and explain how the muscles are named Recognize, define, pronounce, and spell the terms related to the pathology and the diagnostic and tx procedures of the muscular system

Word Parts Bi- Kines/o kinesi/o Ten/o, tend/o, tendin/o -cele My/o Dys- Ton/o -plegia Fasci/o Tri- -rrhexis Fibr/o Tax/o -ia -ic

Fxns of the Muscular System mm hold the body erect and make movement possible m movement generates nearly 85% of the heat that keeps the body warm mm move food through the digestive system m movement, such as walking, aids the flow of blood through veins as it returns to the heart m axn moves fluids through the ducts and tubes associated c other body systems

Structures of the Muscular System Our bodies have more than 600 mm Our mm make up about 40-45% of our body weight Skeletal m is made up of fibers, covered c fascia, and are attached to bones by tendons

Structures of the Muscular System Muscle Fibers Long, slender cells that make up mm Held together by connective tissue and is enclosed in a fibrous sheath Fascia The sheet of fibrous connective tissue that covers, supports and separates mm or groups of mm Flexible but not elastic Myofascial – pertaining to m tissue and fascia

Structures of the Muscular System Tendons Narrow band of non-elastic, dense, fibrous connective tissue that attaches a m to a bone Achilles Tendon attaches the gastrocnemius to the heel bone

3 types: Skeletal, Smooth and Myocardial Types of Muscle Tissue 3 types: Skeletal, Smooth and Myocardial Described according to description and function

Types of Muscle Tissue Skeletal Muscles Attach to the bones of the skeleton and make body motions possible Voluntary muscles We have conscious control over them Striated muscles Under a microscope there are light and dark bands that create a striped appearance

Types of Muscle Tissue Smooth Muscles located in the walls of internal organs Digestive tract, blood vessels, and ducts Fxn: move and control the flow of fluids though these structures Involuntary muscles Under the control of the ANS Unstriated Visceral Found in Lg int organs

Types of Muscle Tissue Myocardial Muscle Myocardium or Cardiac Muscle Forms the muscular walls of the heart Striated like skeletal muscle, but involuntary like smooth muscle It’s contraction and relaxation causes our heartbeat!

Review from yesterday!!!!

Muscle Contraction and Relaxation Muscle Innervation The stimulation of a muscle by an impulse transmitted by a motor nerve Neuromuscular – pertaining to the relationship between nerve and muscle Antagonist Muscle Pairs Antagonist – working in opposition to each other Contraction – tightening of a m Relaxation – when a m returns to it original form

Contrasting Muscle Motion Abduction and Adduction (ABD & ADD) AB-Duction – mvmt of a limb AWAY FROM the midline AD-Duction – mvmt of a limb TOWARD the midline Flexion and Extension ( & /) Flexion – decreasing the angle between two bones by bending a limb at the joint Extension – increasing the angle between two bones or the straightening of a limb Hyperextension – extreme or overextension of a limb/body part beyond normal limits √ is \|/ /_ btwn 2 bones by bending limb @ jt

Elevation and Depression Elevation – the act of raising or lifting a body part Depression – the act of lowering a body part Rotation and Circumduction Rotation – circular mvmt around an axis such as the shoulder joint/neck Circumduction – the circular mvmt of a limb at the far end (the swinging motion @ the distal end of the arm)

Supination and Pronation Supination – the act of rotating the arm or leg so that the palm/sole is turned forward or upward Pronation – the act of rotating the arm or leg so that the palm/sole is turned downward or backward Dorsiflexion and Plantar Flexion Dorsiflexion - D √ - the mvmt that bends the foot upward at the ankle Plantar Flexion – P √ – the mvmt that bends the foot downward at the ankle

How Muscles are Named 1 Muscles are named for their origin and insertion The 2 points where the muscle attaches Origin The less moveable attachment where the muscle BEGINS Located nearest the midline Insertion The more moveable attachment where the muscle ENDS attaching to bone or tendon

O I O I O I

2 How Muscles are Named Muscles named for their Action Named if they’re flexors or extensors Flexor digiti minimi, extensor carpi and flexor carpi muscles

3 How Muscles are Named Muscles names for their location Named for the part of the body or organ they’re near Pectoralis major – the thick fan-shaped muscle on the front of the chest; pectoral means chest Lateralis (lateral) and Medialis (medial) External or Oblique, and Internal 3

4 How Muscles are Named Muscles named for Fiber Direction Oblique – slanted or at an angle Rectus – straight alignment with the vertical axis of the body Sphincter – a ring like muscle that tightly constricts the opening of a passage Transverse – crosswise direction

5 How Muscles are Named Muscles named for Number of Divisions Biceps brachii – biceps; formed from 2 divisions Triceps brachii – triceps; formed from 3 divisions

6 How Muscles are Named Muscles named for their Size or Shape Gluteus Maximus – the larges muscle of the buttock Deltoid Muscle – the shoulder muscle; shaped like an inverted triangle of the Greek letter delta Δ 6

7 How Muscles are Named Muscles named for Strange Reasons The hamstring group… named because that’s the muscles a by which a slaughtered pig is hanged by a butcher Biceps Femoris, Semitendonosis, and Semimembranosis 7

Medical Specialties Related to the Muscular System Exercise Physiologist works under a physician to develop, implement and coordinate exercise programs Neurologist Specialized in muscular disorders where there is loss of fxn Physiatrist Physician who specializes in physical medicine and rehab

Medical Specialties Related to the Muscular System Rheumatologist Physician who specializes in the dx and tx of arthritis, and disorders like osteoporosis, fibromyalgia and tendonitis Sports Medicine Physician Specializes in the tx of sports-related injuries of the bone, joints, and mm

Pathology of the Muscular System Fibers, Fascia and Tendons Fasciitis – inflammation of the fascia Fibromyalgia Syndrome – chronic condition characterized by fatigue, diffuse or specific m, jt or bone p! Tenodynia – p! in the tendon Tendinitis – inflammation of a tendon Chronic Fatigue Syndrome Chronic, debilitating condition. Not like fibromyalgia because it does not go away c rest

Pathology of the Muscular System Muscle Disorders Adhesions – a band of fibrous tissue that holds structures together abnormally Atrophy – weakness or wearing away of body tissues and structures Myalgia – tenderness or p! in the m Myocele – the herniation of m substance thought a tear in the fascia surrounding it

Pathology of the Muscular System Muscle Disorders Myolysis – degeneration of m tissue Myomalacia – abnormal softening of m tissue Myorrhexis – rupture or tear of a m Polymyositis – m disease characterized by simultaneous inflammation and weakness of voluntary mm Sarcopenia – loss of m mass, strength, and pxn that comes c age

Pathology of the Muscular System Muscle Disorders Muscle Tone Known as tonus; the state of balanced m tension Atonic – lacking normal m tone or strength Dystonia – abnormal m tone that causes the impairment of voluntary m movement

Pathology of the Muscular System Muscle Disorders Muscle Tone Hypertonia – excessive tone of the skeletal mm Hypotonia – diminished tone of the skeletal mm Myotonia – a meuromuscular disorder characterized by the slow relaxation of the mm after voluntary contraction

How Muscles are Named Muscles are named for Origin and insertion Their Action Their location Fiber Direction Number of Divisions Their Size or Shape Strange Reasons

PATHOLOGY!!!!!!!

Pathology of the Muscular System Fibers, Fascia and Tendons Fasciitis – inflammation of the fascia Fibromyalgia Syndrome – chronic condition characterized by fatigue, diffuse or specific m, jt or bone p! Tenodynia – p! in the tendon Tendinitis – inflammation of a tendon Chronic Fatigue Syndrome Chronic, debilitating condition. Not like fibromyalgia because it does not go away c rest

Pathology of the Muscular System Muscle Disorders Adhesions – a band of fibrous tissue that holds structures together abnormally Atrophy – weakness or wearing away of body tissues and structures Myalgia – tenderness or p! in the m Myocele – the herniation of m substance thought a tear in the fascia surrounding it

Pathology of the Muscular System Muscle Disorders Myolysis – degeneration of m tissue Myomalacia – abnormal softening of m tissue Myorrhexis – rupture or tear of a m Polymyositis – m disease characterized by simultaneous inflammation and weakness of voluntary mm Sarcopenia – loss of m mass, strength, and pxn that comes c age

Pathology of the Muscular System Muscle Disorders Muscle Tone Known as tonus; the state of balanced m tension Atonic – lacking normal m tone or strength Dystonia – abnormal m tone that causes the impairment of voluntary m movement

Pathology of the Muscular System Muscle Disorders Muscle Tone Hypertonia – excessive tone of the skeletal mm Hypotonia – diminished tone of the skeletal mm Myotonia – a meuromuscular disorder characterized by the slow relaxation of the mm after voluntary contraction

Muscle Disorders Voluntary Muscle Movement Ataxia Dystaxia Contracture The inability to coordinate m activity during voluntary movement Dystaxia Partial ataxia A mild form of ataxia Contracture The permanent tightening of structures occurring when normal connective tissue is replaced w non-elastic fibrous tissues

Muscle Disorders Voluntary Muscle Movement Intermittent Claudication P! in the leg mm during exercise; goes away c rest Spasm Sudden, violent, involuntary contraction of one or more mm Cramp Localized m cramp named for its cause (heat cramp, writer’s cramp, etc) Spasmotic Torticollis Wryneck A spasmotic contracture of the neck

Muscle Disorders Muscle Function Bradykinesia Dyskinesia Hyperkinesia Extreme slowness in movement Dyskinesia Distortion or impairment of voluntary movement such as a tic or spasm Hyperkinesia Hyperactivity Abnormally increased m fxn or activity Hypokinesia Abnormally decreased m fxn or activity

Muscle Disorders Myoclonus The sudden, involuntary jerking of a m or group of mm Nocturnal Myoclonus Thee jerking of limbs that can occur normally as a person is falling asleep Singultus Hiccups Myoclonus of the diaphragm that causes the characteristic hiccup sound c each spasm

Muscular Disorders Myasthenia Gravis Chronic autoimmune disease that affects the neuromuscular junction and produces serious weakness of voluntary mm

Still Pathology…

Muscle Disorders Muscular Dystrophy A group of more than 30 genetic diseases that cause progressive weakness and degeneration of skeletal muscle Duchenne Muscular Dystrophy – most common; usually in boys 3-5 y/o; by 12 most can’t walk and need a respirator Becker Muscular Dystrophy – similar, but less sever than Duchenne.

Repetitive Stress Disorders Caused by repeated motions performed in the course of normal work, ADLs, or sports Compartment Syndrome Compression of nerves and blood vessels in a specific compartment created by the fascia that separates groups of mm Overuse Injuries Minor injuries that have not been given sufficient time to heal

Repetitive Stress Disorders Overuse Tendonitis Inflammation of tendons caused by excessive or unusual use of a joint Stress Fractures We studied these in Ch 3. Overuse; pounding, jumping, crushing stress

Repetitive Stress Disorders Myofascial P! Syndrome Chronic p! disorder caused by the development of trigger points Rotator Cuff Injuries Impingement Syndrome Occurs when inflamed tendons are caught in the narrow spaces between the bone in the shoulder Rotator Cuff Tendonitis Inflammation of the tendons in the shoulder Ruptured Rotator Cuff Untreated tendonitis weakens tendons and they can tear

Repetitive Stress Disorders Carpal Tunnel Syndrome Occurs when the tendons that pass through the carpal tunnel are overused and become inflamed and swollen Creates pressure on the median nerve Causes p!, burning and parasthesia in the thumb, index and middle fingers Release Surgical fix where the tunnel is enlarged

Repetitive Stress Disorders Ganglion Cyst A harmless fluid filled swelling that occurs most commonly on the outer surface of the wrist Epicondylitis Inflammation of the tissues surrounding the elbow Lateral Tennis Elbow Medial Golfer’s or Little Leaguer’s Elbow

Repetitive Stress Disorders Ankle and Feet Problems Heel Spurs A calcium deposit in the plantar fascia near its attachment to the calcaneus Plantar Fasciitis Inflammation of the plantar fascia on the sole of the foot

Sports Injuries Sprain Strain Shin Splint Hamstring injury LIGAMENT injury Strain MUSCULAR injury Shin Splint Condition caused by the m pulling away from the tibia (shin bone) Hamstring injury Any injury, strain or tear, to the mm of the hamstring group Achilles Tendonitis Inflammation of the Achilles Tendon

Spinal Cord Injuries The spinal cord is the consistency of toothpaste, basically, so protection is extremely necessary The type or paralysis is determined by the level of the vertebra closest to the injury The higher up, the great the area of the body that may be affected When the spinal cord is injured, communication with the brain and the area below the injury may be gone or diminished

Spinal Cord Injuries Incomplete Injury Complete Injury The person will have some function below the level or injury, even though that function will not be normal Complete Injury There is complete loss of sensation and m control below the level of the injury. Doesn’t mean to give up hope!

Spinal Cord Injuries Types of Paralysis Paralysis – the loss of sensation and voluntary m movements in m through disease or injury to its nerve supply Myoparesis – weakness or slight muscular paralysis Hemiparesis – slight paralysis or weakness affecting one side of the body Hemiplegia – total paralysis affecting only one side of the body (L brain = R side of the body and vice versa)

Spinal Cord Injuries Paraplegia – paralysis of both legs and the lower body Quadriplegia – paralysis of all four extremities Cardioplegia –Cardiac Arrest; paralysis of the heart m Caused by direct blow or trauma, or medically induced

Diagnostic Procedures of the Muscular System

Deep Tendon Reflexes (DTR) - tested by striking a reflex hammer on a tendon Range of Motion testing (ROM) – procedure used to evaluate joint mobility and muscle strength Electromyography – a test that measures the electrical activity within m fibers in response to nerve stimulation Electroneuromyography – nerve conduction tests; testing and recording neuromuscular activity by electric stimulation of the nerve trunk that carries fibers to and from the m

Treatment Procedures of the Muscular System

Medication Antispasmotic Skeletal m relaxant Neuromuscular blocker Anticholinergic; suppresses smooth m contractions of the stomach, intestine or bladder Skeletal m relaxant Administered to relax certain mm and to relieve the stiffness, p! and discomfort caused by strains, sprains, or other m injuries Neuromuscular blocker A drug that causes temporary paralysis by blocking the transmission of nerve stimuli to the mm

Occupational and Physical Therapy Ergonomics – the study of the human factors that affect the design and operation of tools and the work environment Occupational and Physical Therapy OT – rehab for ADLs. Bathing, grooming, eating, dressing, etc PT – tx to prevent disability or to restore fxn through the use of exercise, heat, massage, and other methods to improve circulation, flexibility and m strength Myofascial Release – soft tissue manipulation to ease p! Therapeutic Ultrasound – high-frequency sound wave to produce deep heat to ease p!, decrease m spasm and accelerate healing

Still under OT and PT Fascia RICE – Rest, Ice, Compression and Elevation; the recipe for injury healing during the 1st few days post-injury Fascia Fasciotomy – surgical incision through the fascia to relieve tension or pressure Fascioplasty – the surgical repair of fascia

Tendons Tenodesis – surgical suturing of a tendon to the bone Tenolysis – a release of a tendon from adhesions Tenectomy – surgical resection/removal of a portion of tendon Tenoplasty – surgical repair of tendons Tenorrhaphy – surgical suturing of divided ends of a tendon Tenotomy – surgical division of a tendon for relief of a deformity caused by the abnormal shortening of a m

Muscles Myectomy – surgical excision of a portion of m Myoplasty – the surgical repair of a m Myorrhaphy – the surgical suturing of a m wound Myotomoy – a surgical incision into a m