Gait and posture

Question 1

What is gait?

Answer 1

Cyclical activity that translocates the centre of the body mass in a forward direction e.g. walking or running

Generally symmetrical and rhythmic but each gait differs from person to person

Question 2

what is bipedalism?

Answer 2

Walking on two limbs

Question 3

Why did hominids develop bipedalism?

Answer 3

• becoming taller to see more of the landscape
• using upper limbs for climbing
• greater movement economy on the ground

Question 4

everybody has a unique gait because gait depends on:

Answer 4

Stride length – determined by by height / leg length

Pelvic movement

Upper body position

Weight and weight carriage

Clothing

Shoes / footwear
Age

Question 5

Normal gait depends on:

Answer 5

Vestibular system

Peripheral nerves

visual system

Motor pathways

Basal ganglia = initiation of movement and coordination of movement

Reflexes and muscle tone being pain free

Question 6

The role of standing in gait

Answer 6

supports body weight

minimises energy expenditure

Question 7

Where is the centre of gravity?

Answer 7

The centre of gravity =
anterior to S2 vertebra

slightly posterior to the hips
anterior to knee and ankle

Question 8

What is the most stable position of the knees and hips

Answer 8

Extension (not bent)

Question 9

In standing, the tendency to fall forward is called

Answer 9

sway

This is counteracted by contraction of soleus

Question 10

What is muscle tone and what are the changes of muscle tone called?

Answer 10

Muscle tone is a feature of skeletal muscle – in the limbs and body wall that is deemed the “firmness”

Hypotonia = reduced muscle tone - ’floppy’

Hypertonia = increased muscle tone - ‘spasticity’ and stiffness

Question 11

Why is muscle tone important?

Answer 11

It helps to stabilise joints and maintain our posture

Question 12

What systems control muscle tone and posture?

Answer 12

sensory inputs, spinal reflexes, descending tracts; the vestibular system and the vestibulospinal tracts important for standing upright

Cerebellar outputs to brainstem and cerebral cortex also involved in postural control.

Question 13

What are the 2 phases of the gait cycle?

Answer 13

Stance phase (foot in contact with ground; 60% cycle)

Swing phase (foot is in the air; 40% cycle)

Question 14

What is stance phrase comprised of?

Answer 14

Heel strike
Loading response
Mid-stance
Terminal stance
Pre-swing

Question 15

What is swing phase comprised of?

Answer 15

Initial swing
Mid-swing
Terminal swing

Question 16

2 types of muscle contraction are:

Answer 16

Isotonic: concentric (shorten) and eccentric contraction (Relax and lengthen)

Isometric: increase in tension of the muscle but it doesn’t change length and there is no movement

Question 17

Heel strike

Answer 17

Begins when the heel strikes ground

Lowering of forefoot to the ground is by the controlled lengthening / relaxation (eccentric contraction) of tibialis anterior

Deceleration of forward momentum due to hip extension (gluteus maximus)

Ankle and subtalar joints accommodate terrain

Question 18

loading response

Answer 18

Foot comes into full contact with ground

Body weight is transferred to stance limb

Quadriceps femoris is key in extending and stabilising the knee and preventing the knee from buckling under the body weight

Question 19

Midstance

Answer 19

Opposite limb swings past stance limb

Requires stabilisation of the pelvis to keep it level – achieved by abduction of hip on stance side by gluteus medius and minimus

Question 20

terminal stance

Answer 20

Heel of the stance limb starts to lift off the ground

Achieved by the plantarflexors – soleus and gastrocnemius

This also accelerates mass forward

Question 21

Pre swing

Answer 21

Final stage of stance phase – preparation for moving into swing phase (i.e. prep for this limb leaving the ground and swinging forward)

Powerful plantarflexion of the digits to push off the ground and accelerate mass forward

In preparation for hip flexion, rectus femoris starts to relax / lengthen (eccentric contraction)

Question 22

Hallux is essential for:

Answer 22

toe off

stabilised by adductor hallucis and abductor hallucis brevis

Question 23

Weak push off (‘apropulsive’ gait) from the toe results in:

Answer 23

shorter stride length

decreased gait velocity

Question 24

initial and mid swing

Answer 24

Hip flexion carries limb forward – iliopsoas and rectus femoris are active (shortening)

Toes & foot are dorsiflexed to allow the foot to clear the ground – tibialis anterior active

Plus knee flexion to shorten limb – hamstrings shorten

Question 25

Terminal swing

Answer 25

In preparation for landing the foot on the ground for heel strike the foot is positioned: to land the foot on the ground: flexed knee is now moved into extension (shortening of the quads, relaxation of the hamstrings – the latter decelerates the limb))

Dorsiflexion of ankle (tibialis anterior) ensures toes clear the ground

Question 26

vertical shift is minimised by

Answer 26

hip abductors

Question 27

lateral shift is minimised by

Answer 27

hip abductors

Question 28

why does gait change with age?

Answer 28

Reduced muscle bulk
Reduced strength and flexibility
Some degree of hearing and vision impairment

Question 29

how do elderly increase gait velocity?

Answer 29

elderly tend to take more steps instead of increasing stride length

Also decreased arm swing and rotation of the pelvis

More flat-footed approach to both heel strike and push off

Question 30

What are the 9 major classifications of gait abnormalities?

Answer 30

Cerebellar ataxia
Hemiparetic gait
Diplegic gait (spastic hemiplegia)
Parkinsonian gait
Sensory ataxic gait
Steppage gait
Myopathic gait
Antalgic gait
Functional gait

Question 31

How do you identify cerebellar ataxia (key characteristics) and what causes it?

Answer 31

Unsteady gait
Incoordination and difficulty with balance
Tendency to jerk sideways
Struggle to narrow feet - appear broad

Can be caused by:

• midline cerebellar lesions that cause truncal ataxia
• chronic alcoholism that leads to cerebellar degeneration

Question 32

How to identify hemiparetic gait and what causes it?

Answer 32

Appearance shows on the affected side

Flexion of the elbow and extension of the lower limb
(affected side appears to be drawing circles with their foot)

the affected limb cannot be shortened by knee flexion when walking

Question 33

How to identify diplegic gait and what can cause it?

Answer 33

Lower limbs are stiff and the hips are adducted

The legs may appear to cross each other and knees seem inverted

Can be caused by:

• cerebral palsy
• MS
• MND

Question 34

what does the Parkinsonian gait appear like?

Answer 34

Shuffling, small steps, difficulty initiating and stopping movement.

When the patient starts walking, their pace increases

Caused by:

• degeneration of the dopamine-producing neurons of the substantia nigra.
• Leads to a combination of rigidity,
• bradykinesia (poverty of movement)
• tremor

Question 35

What does sensory ataxic gait look like and what can cause it?

Answer 35

caused by impaired proprioception

broad based (feet wide apart) and unsteady

Sometimes shows as stomping feet

Positive romberg test: when patient closes their eyes they begin to sway as they cannot depend on their vision

Question 36

What does steppage/neuropathic gait look like?

What can it be caused by?

Answer 36

Weakness of the muscles of the anterior compartment of the leg that dorsiflex the foot = footdrop.

Patients are unable to dorsiflex the ankle of the swing limb and the toes don’t clear the ground

Question 37

How do patients with steppage/neuropathic gait compensate

Answer 37

Flexion of the hip and knee on the affected side so the foot clears the ground.

Question 38

myopathic gait appearance and can be caused by…

Answer 38

waddling appearance
proximal lower limb muscles are weak > unable to maintain level position of the pelvis when one leg leaves the ground

can be caused by muscular dystrophies

Question 39

trendelenberg gait is caused by

Answer 39

Paralysis of the hip abductors of one side (e.g. due to superior gluteal nerve palsy)

Question 40

Antalgic gaits

Answer 40

An antalgic gait occurs secondary to pain

patients cannot put weight onto painful limb

Question 41

functional gaits

Answer 41

‘Non-organic’: i.e. psychological

highly variable presentation that doesn’t fit into any of the other categories