Gait and Posture Flashcards
What does bipedalism refer to?
Walking on 2 feet
Give 3 ways in which peoples gait can differ?
1) Stride length
2) Pelvic movement
3) Upper body position
What 5 things does normal gait rely on?
1) Joints: intact and well functioning
2) Muscles: adequate muscle strength
3) Nerves: CNS and PNS
4) Vision: info about movement of body and head relative to surroundings
5) Vestibular and auditory systems
At what age should children be able to walk alone?
About 1 year (anywhere between 8 and 18 months)
Give the 3 most common reasons for gait changes in the elderly?
1) Decreased muscle bulk
2) Decreased strength and flexability
3) Some loss of hearing and vision
Give the 5 changes to gait that tend to occur in the elderly?
1) Reduction in the overall velocity
2) Reduction in the step/ stride length
3) Decreased arm swing
4) Decreased rotation of the pelvis
5) More flat foot approach to both heel strike and toe push off (shuffling gait)
The center of gravity lies anterior to which vertebra?
S2
Where does the center of gravity lie in relation to a) the hip joints b) the knee and ankle joints?
Lies posterior to the hip joints and anterior to the knee and ankle joints
How is the need for muscular contraction minimised during standing?
The knees and hips are in their most stable position ie. extension
Why is the ankle joint the least stable during standing?
It is flexed rather than extended like the others
What is meant by the ‘forward sway’ that exists when standing?
The tendency to fall forward due to the fact that the line of gravity passes anterior to the ankle joint
How is the forward sway counteracted when standing?
By contraction of the plantar flexor muscles - particularly soleus
What 2 phases can the gait cycle be divided into?
Stance phase
Swing phase
What is meant by double support during the gait cycle?
When both of the feet are in contact with the ground
The stance phase of the gait cycle comprises which 5 phases?
1) Heel strike
2) Loading response
3) Mid stance
4) Terminal stance
5) Pre-swing/ toe push off
The swing phase of the gait cycle comprises which 3 phases?
1) Initial swing
2) Mid swing
3) Terminal swing
What are the 2 main types of muscle contraction?
1) Dynamic contraction - muscle contraction with a change in muscle length
2) Isometric contraction - muscle contraction with no change in length
What are the 2 types of dynamic muscle contraction?
1) Concentric - muscle contraction results in shortening of muscle
2) Eccentric - muscle contraction results in lengthening of muscle
Lowering of the forefoot to the ground during heel strike is controlled by eccentric contraction of what muscle?
Tibialis anterior
Deceleration of forward momentum is achieved by what muscle?
Hip extension by gluteus maximus
During heel strike which muscles are involved in the preservation of the longitudinal arch of the foot?
Intrinsic muscles
Loading response occurs when the foot comes into full contact with the ground and body weight is transferred to the stance limb, what muscle and joint movement is key here?
Extension of the knee by quadriceps femoris to prevent the knee joint from buckling under weight
Mid stance is the point at which the opposite limb swings past the stance limb, it requires stabilisation of the pelvis how?
By abduction of the hip to keep pelvis level, achieved by gluteus medius, minimus and tensor fascia lata
Terminal stance is the point at which the heel starts to lift of the ground, this is achieved by which 2 muscles?
Plantar flexors - soleus and gastrocnemius (Also accelerates mass forward)
Pre swing (toe off) is for preparation for moving into swinging phase - which movement is involved to push off ground and accelerate mass forward?
Powerful plantar flexion of the digits
During pre-swing, slowing of hip extensions and preparation for hip flexion is achieved by which muscle?
Eccentric contraction of rectus femoris
Which digit is essential for toe - off ?
Hallux
Which 2 muscles in hallux stabilised by?
Adductor hallucis and abductor hallucis brevis
If a pt has a misaligned or missing hallux, how does this affect their gait? 2
Weak push off so:
Shorter stride length
Decreased gait velocity
During initial and mid swing hip flexion is achieved by which 2 muscles?
1) Iliopsoas
2) rectus femoris
During initial and mid swing the leg must be shortened to clear the ground, in which 3 ways is this achieved and what muscles are involved in each?
1) Hip flexion - iliopsoas and rectus femoris
2) Toes and foot dorsiflexed - tibialis anterior
3) Knee flexion - hamstrings
What 3 movements have to occur in terminal swing, which muscles are involved in each?
1) Knee flexion change to extension - quadriceps
2) Dorsiflexion of ankle - tibialis anterior
3) Deceleration of limb in preparation for heel strike - eccentric contraction of hamstring muscles
If a patient has limited knee flexion meaning the limb cant be shortened, how is there gait altered and why?
Limb circumduction
Swinging leg moves in an arc rather than forwards which increases the chance of ground clearance for the swing foot
If the foot cant be dorsiflexed ie. foot drop - which nerve is likely to be damaged?
Common fibular
How does a pt with foot drop compensate when walking?
Exaggerated flexion of knee and hip to clear floor
What 2 shifts occur to a persons center of gravity when walking?
1) Vertical shift
2) Lateral shift
What movement reduces the vertical drop in center of gravity when walking?
Pelvic drop
Internal rotation of the stance limb
External rotation of swing limb
Which 3 muscles are involved in internal rotation of the stance limb to reduce the vertical drop in COG?
Gluteus medius and minumus and tensor fascia lata
What 6 muscles are involved in external rotation of the swing limb to reduce the vertical drop in COG when walking?
1) Piriformis
2) Quadratus femoris
3,4) Obturator internus and externus
5,6) Superior and inferior gemelli
What 2 movements limit vertical rise in COG during walking?
1) Knee flexion during stance
2) Pelvic drop to swing side
Which movement limits lateral shift in COG when walking?
Hip adduction (adductors pull knee into midline)
