EXAM 3

Exercise Physiology 364 with Mccrory at West Virginia University

About this deck

By: meredith orndorff
Created: 2011-03-15
Size: 128 flashcards
Views: 39

About StudyBlue

STUDYBLUE makes things that make you better at school. Things like online flashcards with photos and audio. Things like personalized quizzes and friendly reminders about when (and what) to study next. Think of it as a digital backpack™: access to all of your study materials online and on your phone. STUDYBLUE exists to make studying efficient and effective for every student, for free. Join us.

“I have used this website for three exams, and I see a huge difference in my test results.”
Naj

Sign up (free) to study this.

Articulations

structure and function of joints are so interrelated that it is difficult to discuss them separately
configuration of bones and reinforcing ligaments determine and limit the movement of an articulation

Stability and _____ are _________ related.

Range of motion

inversely

Structural Classification of Joints

based on presence of absence of joint cavity

synarthrosis
amphiarthrosis
diathrosis

Further Classification of Joints

By shape or nature of tissues that connect the bones

Synarthrosis Joint

IMMOVABLE JOINTS
NO articular cavity, NO capsule, NO synovial membrane or fluid

Types

1. Sutures

2. Syndesmoses

Sutures

connected by fibers that are continuous with the periosteum

NO MOVEMENT PERMITTED

*skull is the only place sutures are located

Syndesmoses

connected by dense fibrous tissue

EXTREMELY LIMITED MOVEMENT

Ex : coracoacrimial joint (on scapula)

tibiofibular joint

Amphiarthrosis

SLIGHTLY MOVABLE

NO ARTICULAR CAVITY, NO CAPSULE, NO SYNOVIAL MEMBRANE OR FLUID

TYPES:

1. Synchondroses

2. Symphyses

Synchondroses (cartilage)

articulating bones are held together by a thin layer of hyaline cartilage

sternocostal joints (ribs and sternum)

epiphyseal plates in children

Sympheses

fibrocartilage is present between articulating bones

intevetebral joints (between vertebrae)

pubic symphysis (front of pelvis)

Diarthrosis

FREELY MOVABLE JOINT
articular cavity that contains synovial fluid
ligamentous capsule
synovial membrane manufactures synovial fluid
surfaces are smooth and covered with hyaline cartilage

Types: Gliding, Hinge, Pivot, Condyloid, Saddle, Ball and Socket

in TMJ and knee, surfaces are covered with

fibrocartilage

Gliding (planar) Joints

Articular surfaces are flat planes
Movements are non-axial
Short, gliding movements

EX: Intertarsal and intercarpal joints

2 Uniaxial Joints

Hinge Joint
Pivot Joint

Hinge Joint

cylindrical end of bone fits into a trough of another bone
angular movement allowed in one plane
SAGITTAL PLANE --> elbow, ankle, joints between phalanges
movement is UNIAXIAL -- around one axis

Pivot Joint

classified as UNIAXIAL - around one axis
rotating bone only turns around its long axis
EX: proximal radioulnar joint, joint between atlas and axis

2 BI-AXIAL JOINTS

Condyloid Joints
Saddle Joints

Condyloid Joints

convex and concave
allow moving bone to travel

- side to side (ab/adduction)

- back and forth (flexion/extension)

- circumduction

bi-axial movement
EX: wrist joints, metacarpal/phalangeal joints

Saddle Joints

similar to condyloid joints but more bone mass is cut away so joint has MORE ROM
convex and concave
bi-axial movement

EX: first carpometacarpal joint

Tri-axial Joints

1. Ball and socket joints

2. Knee Joint

Ball and Socket Joints

multi-axial movement
shoulder and hip joints
spherical head of one bone fits into round socket of another
moves in all planes (transverse, frontal, sagittal)

Knee Joint : Bicondyloid Joint

two convex and two concave surfaces
more ROM than a typical hinge or condyloid joint
about 8 degrees of rotation can occur when walking
multi-axial movement

Types of cartilage

1. Hyaline

2. Elastic

3. Fibrocartilage

Hyaline Cartilage

most abundant type of cartilage

provides support via flexibility and resilience

Elastic Cartilage

able to tolerate repeated bending

outer ear, tip of nose, epiglottis

Fibrocartilage

(pillow cartilage)

very strong in resisting tension and compression

annulus fibrosis (intevertebral discs), menisci of knee

Articular Cartilage

comprised of hyaline cartilage
consists of chondrocytes, embedded in a matrix of collagen and other proteins
chondrocytes maintain and restore cartilage from wear although this ability decreases with age, disease, and injury

Function of Articular Cartilage

distributes load over wide area to reduce stress on tissues (OVER 50%)
allows movement at joints w/ minimal friction and tear (lubes them up)
acts like sponge to soak up and squeeze out synovial fluid

What makes your knuckles crack?

Nitrogen is within synovial fluid 

Nitrogen gas comes out of fluid bc of low pressure

Forms little Nitrogen gas bubbles that make up on big bubble

When you crack your knuckles, you burst that bubble

“Cracking” is following by decreased pain and increased ROM of joint

Can't crack again until Nitrogen comes out of SF again, 25 to 30 minutes

Joint Stability

ability of a joint to resist abnormal displacement of the articulating bones

INVERSELY PROPORTIONAL TO ROM

Close packed position

MOST STABLE POSITION

joint orientation where contact between articulating surfaces is at a MAX

Loose packed position

any other joint orientation that is not close packed

Factors contributing to Joint Stability

Bone structure
Ligaments
Muscle tone/tension
Fascia
Atmospheric Pressure

Bone structure

may refer to type of joint
JOINTS MOST STABLE TO LEAST STABLE

hinge
condyloid
ball and socket

may refer to specific characteristics of joint

(depth of joint socket)

As a general rule, the more articulating surfaces are in contact with one another,

the more stable the joint is

Ligaments

Strong, flexible, stress-resistant fibrous tissues that form bands around joints

Help to maintain relationship of bones

Will stretch when subjected to prolonged stress
Once stretched, their function is affected
Medical intervention is needed to shorten them

Muscles

Muscle force can help to stabilize or destabilize joint, depending on joint position

Particularly helpful in stabilizing a joint when bony structure has little stability

Fascia

Fascia consists of fibrous connective tissue

May form thin membranes or tough fibrous sheets

Intense or prolonged stress may cause permanent damage

Atmospheric Pressure

pushes on outside of joint w/ a greater force than the outward pushing force w/in a joint cavity

Knee stability

very unstable joint
contact of articulating surfaces is minimal, resulting in large ROM
dependent on ligaments/tendons for stability
injuries are common

Factors influencing Joint ROM

Shape/ Contact area of articular surfaces (BONE STRUCTURE)
Restraining effect of ligaments
Muscles and tendons

+ gender, body build, heredity, occupation, exercise, age

Measuring Joint ROM

measure degrees from starting position or anatomical position to its max movement

during activity ---> you can use film or electric goniometers a person can wear

goniometer

tool that measures joint angles

1. axis placed directly over center of joint

2. one arm held stationary

3. other arm held to moving segment

flexibility and injury

injury is HIGHER when joint flexibility is

EXTREMELY HIGH or EXTREMELY LOW

decreased flexibility in older age

caused by sedentary lifestyle

Propioceptors

respond to degree, direction, & rate of change of body
transmit info to CNS
muscle receptors

- muscle spindles, golgi tendon organs

joint and skin receptos

- ruffini endings, Pacinian corpuscles

Types of Efferent Neurons

1. Alpha efferent neuron

2. Gamma efferent neuron

Alpha Efferent Neuron

motor neuron that activates / inhibits muscles

Gamma Efferent Neuron

neuron that presets sensitivity of propioceptor

very active when REFLEXES must be SHARP

(ex. walking on ice or into dark room)

Muscle spindles

"intrafusal" muscle fibers
located in muscle belly
more spindles in muscles controlling precise movements

Summary of Stretch Reflex

1. Muscle gets stretched

2. Muscle spindle is activated by change in length of muscle

3. Afferent message is sent to spinal cord

4. Alpha motor neuron is activated

5. Muscle that is stretched is activated and antagonist is inhibited

efferent neuron path

SPINAL CORD to MUSCLE SPINDLE

afferent neuron path

MUSCLE SPINDLE to SPINAL CORD

efferent activates muscle

SPINAL CORD to BELLY OF MUSCLE

afferent activates muscle

SPINAL CORD to BELLY OF MUSCLE

nerve to brain

tells brain what happened

reciprocal inhibition

when muscle is inhibited by neuron

Importance in Standing Posture

Soleus is primary posture muscle
If person sways forwad, muscle spindles in soleus are activated
Stretch reflex is activated
Soleus is activated and tib ant is inhibited
Person then sways back to begin cycle again

COM

center of mass is anterior to ankle so a person ALWAYS sways forward when standing

why soleus is so important

Spasticity

overactive stretch reflexes
common in people w/ neurological disorders (cerebal palsy, stroke)

Spasticity in response to fast stretch

beating motion called CLONUS

Spasticity in response to slow stretch

continuous activation

Treatment for spasticity

1. Temporary - BOTULISM TOXIN (BOTOX)
2. Permanent - DORSAL RHIZOTOMY (SURGERY)

Golgi tendon organs

embedded in the tendon

in muscle tendon junction on tendon side

GTO activated by

increased tension

Muscle spindles activated by

stretch

Function of GTO

signals CNS to relax muscle

PROTECTIVE MECHANISM

Reflex Inhibition

1. tendon is under high tension

2. GTO is activated by tension level

3. afferent message is sent to spinal cord

4. alpha motor neuron is activated

5. muscle of tendon under tension is inhibited

6. antagonist muscle is activated

Pacinian Corpuscles

reflex loop measures FAST THINGS

located in regions around joint capsules, ligaments, and tendon sheaths
measure acceleration, rapid movement of joints, and joint pressure
transmit impulses for only a BRIEF TIME
predict where body will be at any time
appropriate adjustment in position can be anticipated

Ruffini Endings

TELL YOU WHERE YOU ARE AT REST AND WITH SLOW MOVEMENT

in deep layers of skin and joint capsules
activated by mechanical deformation
signal continous states of pressure
adapt slowly, transmit steady signal
sense joint position and changes in joint angle

active stretching vs. passive stretching

stretching where you actively develop tension in antagonist muscles

vs.

stretching where you use another person or another force other than antagonist muscles to move body segment to end of ROM

static vs. ballistic stretching

holding a slow, controlled, sustained stretch for over 30 seconds

vs.

a series of quick, bouncing type stretches

benefit of active vs passive

more chance of injury with passive stretching by going past ROM

benefit of static vs. ballistic

more likely to tear or rupture tissues with ballistic stretching

which stretching using muscle spindles

active stretching

which stretching uses GTOs

passive stretching

proprioceptive neuromuscular function

require partner/clinician
originally used for treating neuromuscular paralysis
Take advantage of GTO response by alternative contraction and relaxation of antagonist muscle

Joint Injuries

1. Sprain

2. Subluxation

3. Dislocation

4. Torn intracapsular cartilage

Sprain

First degree: minor tear or stretch 

Second degree: tear, followed by pain and swelling 

Third degree: complete ligamentous rupture 

Fourth degree: complete rupture, along with some small 

bone

Subluxation

incomplete / partial dislocation

Dislocation (luxation)

displacement of the articulating bones

*usually requires medical treatment to reduce

Torn intracapsular cartilage

cartilage within joint capsule is torn

*often repaired with athroscopic surgery

Joint disorders

Bursitis

Arthritis

1. Osteoarthritis

2. Rheumatoid arthritis

3. Gout

Bursitis

inflammation of bursa

Arthritis

inflammation of joint

Osteoarthritis

wear and tear arthritis

Rheumatoid arthritis

autoimmune disorder in which immune system attacks SYNOVIAL JOINTS

gout

uric acid crystalizes in the joint

Functions of Muscle tissue

movement
posture
joint stabilization
heat generation

body temp while working out

101.3 degrees F

Tissues in Musculotendinous Unit

1. Muscle cells (fibers)

2. Tendons

3. Connective Tissue and Fascia

Epimysium
Perimysium
Endomysium

Epimysium

surrounds entire muscle

Perimysium

surrounds each fasicle

Endomysium

surrounds each muscle cell

Behavioral Properties of Musculotendinous Unit

Contractility

Excitability

Extensibility

Elasticity

Contractility

ability to shorten to generate force

Excitability

aka Irritability

ability to react to a stimulus (electrical nerve impulse)

Extensibility

ability to be stretched

Elasticity

ability to recoil after being stretched

active tissue

what responds to stimuli

Contractile Component "CC"

Passive tissue

SEC and PEC

series elastic component and parallel elastic component

hyperplasia

increasing # of muscle fibers that we have

most evidence says you are born w/ the amount you will have forever except you can lose them to injury

Dr. Haff is studying to see if you can gain any

sarcomere

basic unit of muscle cell

actin (thin filaments)

extend from Z disc toward center of sarcomere

LIGHT FILAMENTS

myosin (thick filaments)

located in center of sarcomere

DARK FILAMENTS

*overlap inner ends of thin filaments

* contain ATPase enzymes

Titan filament

holds myosin in place

not involved in contraction

Z-disc

boundaries of each sarcomere

A bands

full length of thick filament

includes inner bands of thin filaments

*remember A in dark

H zone

center part of A band where no thin filaments occur

M line

center of H zone

contains tiny rods that hold thick filaments together

I band

region w/ only thin filaments

(remember I in light)

sarcoplasmic reticulum

an elaborate smooth endoplasmic reticulum made of interconnecting tubercles

sliding filament mechanism

myosyin heads attach and pull actin towards middle

ACTIN IS THE ONLY PART THAT MOVES (ladder above that is moving)

myosin does not move, held by titin

Motor units

Single motor neuron and all fibers it innervates

COMPRISED OF: 1. nerve cell body

2. nerve axon

3. all muscle fibers innervated by nerve fiber

Muscle characteristics

Most motor units are TWITCH TYPE (respond to single stimulus)

Eye muscles are TONIC TYPE (need multiple stimuli to contract)

with one stimulation

you get a set amount of force

summation

building tension/force in an additive fashion in response to repeated stimulation

tetanus

state of sustained MAX tension resulting from repetitive stimulation

ALL myosins have grabbed on to actins, you cannot get any more force

Fiber types

categorized by

1. how they manufacture energy (ATP)

2. how quickly they contract

3 types

TYPE 1 -- Slow oxidative fibers

TYPE 2A -- Fast oxidative glycolytic fibers

TYPE 2B -- Fast glycolytic fibers

Slow oxidative fibers

RED

endurance, aerobic, slow to fatigue

Fast oxidative glycolytic fibers

PINK

no endurance

anaerobic, fatigue quickly

Fast glycolytic fibers

WHITE

no endurance

anaerobic, fatigue quickly

dorsal spinal cord

back

SENSORY

to brain

ventral spinal cord

front

MOTOR

to body

intrafusal

activated by alpha efferent neurons

extrafusal

activated by gamma efferent neurons

About this deck

By: meredith orndorff
Created: 2011-03-15
Size: 128 flashcards
Views: 39

About StudyBlue

“I have used this website for three exams, and I see a huge difference in my test results.”
Naj