Exam 3 Flashcards
What is center of gravity?
Point at which total mass of the body is equally distributed
Anterior to S1
55-57% of height
What is stability?
Ability to resist movement
What is mobility?
Ability to move readily
What factors affect stability?
Size of bass Height of Center of Gravity Location of Center of gravity Body mass Friction Visual, psychological and physiological
What are the three types of equilibrium?
Stable
Unstable
Neutral
What is stable equilibrium?
Disturbing an object raises center of gravity
What is unstable equilibrium?
An object will move in the direction of displacement
What is neutral equilibrium?
Center of gravity neither raised nor lowered with external force
What is posture?
Alignment of the vertebral column and its parts
What is balance?
The maintenance of posture
What are the functions of posture and balance?
Help maintain body segment alignment
Allows for effective engagement in voluntary movement
Reacting to unexpected balance disturbances
What is dynamic posture?
Posture of motion
What is static posture?
Involves little motion, but not necessarily motionless
What happens when postural control fails?
We engage muscles not suited for activity
Biomechanics suffer
What is standing posture?
Head erect
Even weight distribution
Even bilateral structures
What is sitting posture?
Anterior pelvic tilt
Both feet flat on floor
Both palms on surface
What is static postural control?
Allows for maintenance of center of gravity with the base of support
Happens with postural sway
What is reactive postural control?
Allows for maintenance of balance in response to unexpected events
Righting response
What is anticipatory postural control?
Movements in anticipation of a loss of balance
What is adaptive postural control?
Allows for movement modification for prolonged activity
What is the hip joint comprised of?
Right and left coxae and sacrum (pelvic girdle)
What does the hip joints stability come from?
Bony architecture
Strong ligaments
Large supportive muscles
What bone is weight bearing in the lower leg?
Tibia
What are the structures of the patella?
Superior base
Inferior apex
Articular facets
What are the ligaments of the knee?
Transverse Anterior cruciate Posterior cruciate Tibial collateral Fibular collateral Oblique popliteal Arcuate popliteal
What does the transverse ligament do?
Connects menisci to each other
In front of knee
What does the anterior cruciate ligament (ACL) do?
Main ligament in knee stability
Connects front of tibia to back of femur
Prevents femur posterior displacement
What does the posterior cruciate ligament (PCL) do?
Connects front of femur to back of tibia
What does the tibial collateral ligament(MCL) do?
Connects tibia to femur (medial)
What does the fibular collateral ligament (LCL) do?
Connects fibula to femur
Laterally
What does the oblique popliteal ligament do?
Enforces medial-posterior corner of the knee
What does the arcuate popliteal ligament do?
Connects head of fibula to condyles
What are the two lines of pull that is equal to Q angle?
ASIS to patella
Center of patella to tibial tuberosity
What is normal Q angle for men?
Women?
Less than or equal to 15 degrees
Less than or equal to 20 degrees
What are the proximal tarsal bones?
Calcaneous
Talus
Navicular
What is the lateral longitudinal arch?
Extends from heel to little toe
What is the longitudinal arch?
Extends from heel to halluc
What is les planus?
No arch when in weight bearing position
What is pes cavus?
Heightened arch
What are the three causes of gait abnormalities?
Trendelberg gait
ACL deficiencies
Neurological conditions
What is locomotion?
The act or power of moving from place to place
What is gait?
A particular form of locomotion
What is walking?
Upright bipedal locomotion that consists of two phases
What are the characteristics of stance phase?
60% of the time
Heel contact, foot flat, midstance, heel-off, toe-off
What are the two phases of walking?
Stance phase
Swing phase
What are the steps of swing phase of walking?
Initial, mid and terminal swing
What is cadence?
Number of steps taken per minute
What is slow cadence?
Fast?
Male average?
Female average?
Slow 70
Fast 130
Men 113
Women 117
What is crawling?
Locomotion on both hands and stomach
What is creeping?
Locomotion on hands and knees
What must occur for gait to fully develop?
Increase hip ROM Increased ankle ROM Decrease step width Increase stride length Enhanced counterbalance muscle activity
What are the phases of running?
Swing
Stance
Float
What is the float phase?
Period of nonsupport
At what speed does running begin?
4.5mph
What is jumping?
Leave from two, land on two
What is leaping?
Leave from one, land on the other
What is hopping?
Leave from one, land on the same
What is assemble?
Leave from one, land on two
