Exam 2 Flashcards
specific gravity of water
1
object with specific gravity more than 1 will
sink
object with specific gravity less than 1 will
float
definition of specific gravity
a ration of an objects weight to the weight of an equal volume of water
specific gravity of humans
0.95-0.97
-obese 0.93 (float)
-lean 1.10 (sink)
Archimedes principle of buoyancy
a body partially or fully immersed in a fluid will experience an upward thrust of that fluid that is equal to the weight of the fluid the body displaces
what does a specific gravity of 0.95 mean (% of floating and submerged)
95% body is submerged
5% of the body is floating
center of buoyancy
buoyancy is the upward force
gravity is the downward force
viscosity of water
resistance to movement within a fluid caused by the friction of the fluid molecules
-aka water resists the movement
is the resistance to a body that is moving through it
drag
form drag
resistance that an object encounters in a fluid
-size and shape
-larger has more drag (turbulence)
wave drag
is the waters resistance because of turbulence caused by the speed of an object in the water
-change positions and speed
friction drag
result of waters surface tension
-competitive swimmers
-shaving arms and legs
Pascals law of Hydrostatic pressure
states that pressure from a fluid is exerted equally on all surface of an immersed object at any given depth
-deeper = greater pressure (ears pop)
what can hydrostatic pressure have a positive effect on
-post injury edema
-exercise without risk (better optimal loading)
whose center of gravity is higher
males COG is higher than females
-% of body weight borne at different depth varies between males and females
advantages of aquatic therapy
-restricted weight bearing
-relaxation of muscles
-reduced joint compression = reduced pain
-warmth = overrides sensory system = relaxation and increased ROM
-reduced stress on muscles
precautions of aquatic therapy
-fear of water
-medications (HR, BP, respiration, cardiorespiratory function)
-ear infections (cover the ear)
-specific conditions: diabetes, CV disease, seizures, sensitive to pool chemicals
contraindications to aquatic therapy
-illness
-open wounds
-other medical conditions (DVT)
differences of running gait from walking gait
-shorter stance phase
-lengthened swing phase
-no double support
-nonsupport phase = double float phase
running stride
the time during a running cycle when one foot makes contact with the ground to the time the opposite foot contacts the ground
running cycle
cycle that includes 2 running strides
cycle time
amount of time it takes to perform one step length
stride rate
inverse of stride time
foot strike
initial contact
what increases as velocity of running gait increases
stride length and stride rate
what decreases with an increases in speed of running gait
cycle time
parts of swing running phase
-initial swing (double float at start)
-midswing
-terminal swing (double float at end)
parts of stance running phase
-absorption
-midstance
-propulsion
types of assistive devices depend on
-patients age and size
-physical ability and coordination
-balance
-specific injury
-weight-bearing status
-comfort level
device selection is dictated by
the weight-bearing required for optimal recovery after an injury or surgery
NWB ambulation
-no weight permitted
-two crutches or walker
PWB
-WB without pain
-two crutches or walker
TTWB (toe-touch) and TDWB (touch-down)
-PWB with touching toe to the ground for stability
-two crutches or walker
WBAT
-no WB restrictions
-two crutches -> one crutches or cane before eliminating them all
proper fitting of crutches
-6 inches lateral and 6 inches anterior to the toes
-2-3 fingers width from crutch to axilla
-20-30 degree elbow bend
proper fitting of canes
-with canes next to leg, top of cane handle is at wrist or greater trochanter
-20-30 degree elbow bend
two-point gait
PWB allowed on involved extremity
three-point gait
-axillary crutches, forearm crutches, walker
-NWB on one leg
-swing to or swing through gait
four-point gait
-used for those who have bilateral lower-extremity involvement
-involves using one crutch with each contralateral leg
single support ambulation
-1 crutch or cane
-both feet on floor
-used for stability and balance
-device moves with the injured leg
how to use assistive devices on the stairs
-up with the good
-down with the bad
-device always goes with the injured leg
how to use assistive devices on ramps
-device and injured leg kept together
-take shorter steps
safety instructions and precautions with assistive devices
-inspect equipment for wear and damage
-remove throw rugs
-environmental conditions: use caution in rain, ice, snow
-keep assistive devices close to the body to avoid tripping others
-do not rest axillae on axillary pads
body’s ability to transmit afferent information about position sense, to interpret the info, and respond consciously or unconsciously to stimulation through appropriate execution of posture and movement
proprioception
proprioception is targeted in therapeutic exercise after
flexibility, strength, and endurance have improved
components of proprioception
agility
balance
coordination
proprioceptors
afferent nerves that receive and send impulses from stimuli within the skin, muscles, joints, and tendons to the CNS
-send info about tension of the muscles, position of body part, etc
types of cutaneous receptors
fast adapting afferents
slow adapting I and II afferents
fast adapting afferent cutaneous receptors
-detects sudden changes in speed and movement
-send lots of info quickly to CNS
slow adapting I and II afferents cutaneous receptors
-produce constant level of stimulation and provide info related to joint and limb position
injured subjects have increases reliance on these receptors for proprioception
cutaneous
GTOs
detect tension, respond to contraction and stretch, produce relaxation
muscle spindles
respond to stretch, cause contraction
muscle spindles and GTOs
-work together to facilitate actions of opposing muscles and synergists
-determine joint position because of muscle-length sensitivity
-act as limb stabilizers
types of joint receptors
group II afferents
groupt III and IV afferents
group II afferents joint receptors
-similar to A-beta
-large diameter, myelinated axons with high speed conduction
-ruffini endings, Pacinian corpuscles, golgi-mazzoni corpsucles
group III and IV afferents joint receptors
-group III are A fibers
group IV are C fibers
-small diameter, thinly myelinated or no myelinated axons with slower conduction
-free nerve endings in soft tissue and articular surfaces
-nocieceptors stimulated by pain and inflammation when a joint is placed in any end position
ligament receptors
-stimulated by ligamentous stress
-produce inhibitory response of agonist muscles: ruptured ACL prevents quad muscles from contracting
T/F the CNS cannot determine the position of an extremity unless it receives input from all sensory, motor, and joint receptors
true
spinal cord
-spinal reflex or internuncial connections
-quickest response
brainstem
-cerebellum: primary proprioceptive correlation center
-posture and balance
cerebral cortex
-volitional control
-correct movement learned and consciously controlled
-slowest response, becomes automatic
balance
body’s ability to maintain an equilibrium by controlling its COG over its base of support
3 systems of balance
vestibular
oculomotor
somatosensory
what influences balance
strength and sensory input from CNS
vestibular system
vertical and horizontal position and motion
-ear
oculomotor system
relative position of body in space
somatosensory system
proprioception
static testing of balance
Romberg
BESS
dynamic testing of balance
SEBT
Y-balance
closed kinetic chain upper extremity stability test
what produces relaxation of a muscle
GTOs
coordination
complex process by which smooth pattern of activity is produced through a combination of muscles acting together with appropriate intensity and timing
components of coordination
-perception of activity
-feedback and feedforward
-performance adjustment
-repetition (develops engram and accuracy)
-inhibition
how is coordination accomplished
complex neural network of sensory receptors, internuncial neurons, ascending and descending corticospinal pathways, and afferents receptors
overflow
with increased voluntary effort or prolonged effort, motor activity spreads to additional motor units of the same muscle and to motor units of other muscles
what produces incoordination
overflow
what causes incoordination
weakness
feedback
sensory and visual input -> cerebral cortex/cerebellar response/spinal reflex -> muscle activity -> feedback on performance from sensory and visual
feedforward
sensory and visual input -> cerebral cortex/cerebellar response/spinal reflex -> muscle activity
agility
ability to control the direction of a body or its parts during rapid movement
-built on flexibility, strength, power, followed by coordination and balance
general concepts of exercise progression
-balance first, then coordination, then agility
-simple to complex
-initial exercises are slow and controlled
-advance only after goal is achieved or activity is mastered
when should you do proprioceptive exercises
early in the session when less fatigued
swinging a baseball bat at a pitch would most likely use what to ensure accuracy
feedforward
during upper extremity ABC rehab, what would be the last step
functional/performance specific activities
exercising a sprained ankle in water can help reduce what in the ankle
both pain and edema
appropriate order in which problems are addressed in a rehab program
flexibility, strength, functional progression activities, performance-specific
T/F the brain stem is where conscious correction of motor performance originates
false
injured patients have an increases reliance on which receptors
cutaneous
T/F a larger object has more drag in water than a smaller object
true
what statements describe feed forward information
-movement is based on previous knowledge of the activity
-info on the accuracy comes after the movement is completed
-information is used to predict the success of the movement
T/F the Romberg test is used to assess agility deficits
false
which exercise places the least load or compression on the body
walking in shallow water
a patients arm will have more resistance in the water if they move their arm
faster
which should be used as transition parameter to advance functional activities
proprioception
T/F strength does not play a role in balance
false
examples of group II afferents nerve endings
ruffini and Pacinian corpsucles
the quickest proprioceptors neural response occurs with efferent impulses that are initiated in the
spinal cord
T/F ab object with a specific gravity of 1.5 will NOT float in water
true
a patients using assistive devices is more stable because he or she has
a wider base of support
running gait differs from walking gait in that the stance phase is ___ and the swing phase is ___
stance phase is shortened
swing phase is lengthened
which side does the cane go
opposite of injured leg
