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