L: Walking and Gait Flashcards
What is gait?
Mechanism by which the body is transported using co-ordinated movements of the major lower limbs
Require energy-efficient interaction between musculoskeletal and neurological systems
What are the two phases of gait?
Stance phase: 60% cycle, time in which the foot is in contact with the ground
Swing phase: 40% cycle, time when foot is not in contact with the ground
What is the gait cycle?
Period of time from the initial contact to next initial contact on same side of body
What are 5 important things that are needed for normal gait?
- Stability in stance: transfer weight from one side of the body to the other
- Foot clearance during swing phase: Raise the foot off the ground as its brought forward
- Pre-positioning for initial contact: prepare the position of the foot for the next stance phase
- Adequate step length: lower limb brought forward by suitable distance during the swing phase, before making contact with the ground during the next stance phase
- Energy conservation: movements need to be energy efficient
What normally makes the first contact during normal gait?
Heel normally makes contact first
What is meant by period of double support?
The point in time when both feet are in contact with the ground
What happens to the period of double support as you being to walk faster/ start running?
Period of double support decreases in length
Period of double float–> both feet are off the ground
What happens to the normal gait cycle during sprinting?
Stance and swing phase reverse
40% stance phase
60% sprint phase
What are the different stages of the stance phase?
Initial contact- ‘heel strike’ heel makes initial contact
Loading response- Decceleration, knee and ankle joint absorb impact, heel rocks forward ready for whole foot impact
Mid-stance- Foot is flat in the ground, centre of gravity shifted from back to front, ready for forward propulsion
Terminal stance- Ankle is plantarflexed, heel of supporting leg raised from ground
Pre-swing- metotarsalphalangeal joints flex to give’ push off’ by toes
What are the different stages if the swing phase?
Initial swing- Knee flexes to enable foot to clear the ground
Mid-swing- Hip flexes, pelvis swings forward enable forward progression, dorsiflexion of the ankle to neutral position
Terminal swing- knee extends, foot brought close to the ground in preparation for heel strike
What is responsible for the forward progression?
Push off of the toes
Powerful plantarflexion of the ankle
Flexion of the hips
Swing movement of the pelvis
Define stride?
Distance from initial contact with one leg to the next initial contact with the same leg
Define step?
Distance from initial contact with one leg to initial contact with the other leg
Two steps with every stride
Define cadence?
Number of steps per minute
What is gait analysis? What are the elements?
Study of a person’s gait
Kinematics–> describe the motion’s –> joint angles, displacements, velocities and accelerations that take place during gait
Kinetics–> describe force and moments that cause motion
Measured at the hip, knee and ankle
What are the three ways in which muscles work?
Concentric contraction–> muscle shortening
Eccentric contraction–> muscle lengthening
Isometric contraction–> muscle same length
What are the roles of the muscles during gait?
Initial contact–> heel strike, tibialis anterior (dorsiflexor) works eccentrically, stops the foot slapping the ground during–> deceleration
Mid stance–> tibialis anterior relaxes
Terminal stance–> gastrocneium and soleus concentric contraction to plantarflex ankle and generate powerful propulsion
How is energy conserved during normal gait?
- Minimise movement of centre of gravity
- Control momentum
- Transfer energy passively between body segments using elasticity in the tendons and ligaments
- Phasic muscle action: using muscles intermittently, fatigues less rapidly
What can cause gait abnormalities?
Nerve lesions, joint instability, immobility of joints and pain
What are the different types of gait abnormalities?
Antalgic gait Trendelenburg gait Hemiplegic gait Diplegic gait High-steppage gait Parkinsonian gait Ataxic gait
What is antalgic gait?
Walk to reduce pain
Walk with a limp
Spend more time in stance phase on less painful limb
Reduced swing phase in unaffected limb–> uneven gait
Walking stick–> used in hand opposite to painful limb
–> shift centre of gravity onto it so that less weight through painful limb during stance phase
What is Trendelenburg gait?
Hip adductors normally contract preventing pelvis dropping on unsupported side
Mechanism fails–> positive Trendelenburg sign and Trendelenburg gait
Stance phase–> Pelvis drops on the unaffected side
Compensated response–> patient shifts torso to affected side
What can causes Trendelenburg gait and sign?
Lesion in superior gluteal nerve
Muscle pain and inhibition of function
Trauma –> fraction of greater trochanter (Insertion of G. Medius), or hip dislocation
Biomechanical hip instability
What is Hemiplegic gait?
Paralysis of one side of body e.g stroke, cerebral palsy, trauma of CNS
Spasticity (continuous contraction) of affected side of body
Most severe in flexors (upper limb) and extensors (lower limb)–> dominant muscle groups
Patients–> flexed upper limb and extended lower limb
Cannot flex hip, knee or ankle
Weight transferred to unaffected side of body and circumduction of paralysed leg
Paralysed leg cannot bear much weight so short stance phase
What is diplegic gait?
Spasticity affects both lower limbs
Most common in cerebral palsy
Narrow based gait–> drag both legs and toes
Scissoring–> spasticity of hip adductors means legs cross midline
Spasticity of hamstings–> Knees slightly flexed
Spasticity of gastrocnemius and soleus–> plantarflexion of foot
Forefoot usually makes initial contact (normal gait=heel)
What is high-steppage gait?
Weakness of ankle dorsiflexion –> foot drop
Foot raised off ground in swing phase–> absence of dorsiflexion means foot assumes plantarflexion position
Flexion of hip much more to stop toes dragging along the floor
Tibialis anterior absent so foot slaps down on the floor–> no controlled eccentric contraction
If deep peroneal nerve affected but superficial intact–> compensate for lack of dorsiflexion by eversion flick –> sudden eversion of foot
What are the causes of high-steppage gait?
Common peroneal nerve palsy –> trauma to nerve, compression of nerve, peripheral neuropathy
Sciatica–> L4 myotome dorsiflexes ankle
Neuromuscular disease
PED- common Peroneal Evert and Dorsiflex (injury= foot drop)
Whats is parkinsinian gait?
Nerve cells in substania nigra degenerate–> reduction in dopamine –> regulates body movement
PD patients difficult to initiate movement
Flex their necks and trunk–> centre of gravity in front of lower limbs
Short steps –> Festinant gait–> accelerating steps
Loss of arm swing–> diagnostic sign
What is ataxic gait?
Clumsy staggering movemens
Wide broad base, arms often out to help with balance
Standing still–> body sways backwards and forward and side to side–> titubation
Patients unable to walk heel to toe or in a straight line
What causes ataxic gait?
Proprioceptive (loss of awareness of position of joints)
Cerebellar disease
Vestibular damage (damage to organs of balance in inner ear)
Cerebellar dysfunction (inherited, acquired or alcohol intoxication)
- Cerebellum normally coordinates elements of movement resulting smooth and balanced muscular activity
What happens if you injury the tibial nerve?
TIP= Tibial Inverts and Plantarflexes (injury= can’t walk on TIPtoes)
