Human Gait

HUMAN GAIT
Dr. Hazrat Bilal Malakandi, PT
DPT (IPM&R, KMU), MSPT (KMU), CHPE (KMU)
Senior Lecturer (NCS University System, Peshawar)

INTRODUCTION TO
HUMAN GAIT
Human gait may be
define as “ the
translatory progression
of the human body as a
whole, produced by
coordinated, rotatory
movements of the body
segments” is known as
gait or human
locomotion

TASKS
Winter proposed the following five tasks for
walking:
1. Maintenance of support of HAT
2. Maintenance of the upright posture and balance of the
body
3. Control of the foot trajectory to achieve safe ground
clearance and gentle heel or toe landing.
4. Generation of the mechanical energy to maintain the
present forward velocity or to increase forward velocity
5. Absorption of the mechanical energy for shock
absorption and stability or to decrease the forward
velocity of the body

GAIT INTIATION
 Gait initiation may be defined as an activity that
includes the series or sequence of events that occur
from the initiation of movement to the beginning of
gait cycle.
 Gait initiation begins in erect standing posture with
activation of the tabilais anterior and vastus lateralis
muscles, in conjunction with an inhibition of the
gastrocs muscles, bilateral concentric contraction of
the tabilais anterior muscles results in a sagittal torque
that inclines the body anteriorly from ankles.

 The CoP is described as shifting either
posteriorly and laterally or posteriorly and
medially.
 Abduction of the swing hip occurs almost
simultaneously with contractions of the tabilais
anterior and vastus lateralis muscles and
produces a coronal torque which propel the body
toward the support limb.
 Total duration of the initiation phase is about
0.64 seconds.

KINEMATICS
Phases of the Gait cycle
 Gait cycle which is also called as stride is the time
interval or sequence of motions which occurs
between two consecutive initial contacts of the
same foot i.e. from heel strike of the right
extremity to heel strike again of the right
extremity
 Distance covered one gait cycle is called the stride
length

PHASES OF GAIT CYCLE
During gait cycle each extremity passes through two
major phases
1. Stance phase----60%
2. Swing phase-----40%
 There are two periods of “double support” in
which one extremity is in initial contact and the
other one leaves the ground

 At normal walking speed each period of
double support occupies 11% of the gait
cycle which a total duration of 22% of the
gait cycle, normally 20% is used.
 The body is supported on a single limb for a
duration which makes 80% of the gait
cycle.

DIVISONS OF PHASES
Two most common terminologies for the divisions
of phases into events of the gait cycle are
1. Traditional (T)
2. Rancho Los Amigos (RLA)
In both conventions the gait cycle is divided into
percentiles that will be used to clarify events and
phases

EVENTS IN STANCE PHASES
1. Heel contact or heel strike (T) refers to the
instant at which the heel of the leading extremity
strikes the ground. Initial contact (T and RLA)
refers to the instant the foot of the leading
extremity strikes the ground.
In normal gait, the heel is the point of contact. In
abnormal gait, it is possible for the whole foot or
the toes, rather than the heel, to make initial
contact with the ground. The term initial contact
will be used in referring to this event.

2. Foot flat (T) in normal gait occurs after initial contact
at approximately 7% of the gait cycle . It is the first
instant during stance when the foot is flat on the
ground.
3. Midstance (T) is the point at which the body weight is
directly over the supporting lower extremity. usually
about 30% of the gait cycle. Heel-off (T) is the point at
which the heel of the reference extremity leaves the
ground , usually about 40% of the gait cycle.
4. Toe-off (T and RLA) is the instant at which the toe of
the foot leaves the ground , usually about 60% of the
gait cycle.

EVENTS IN SWING PHASES
1. Acceleration, or early swing phase (T),
begins once the toe leaves the ground and
continues until midswing, or the point at
which the swinging extremity is directly
under the body .
2. Initial swing (RLA) begins when the toe
leaves the ground and continues until
maximum knee flexion occurs.

1. Midswing (T) occurs approximately when the
extremity passes directly beneath the body, or from
the end of acceleration to the beginning of
deceleration. Midswing (RLA) encompasses the
period from maximum knee flexion until the tibia is
in a vertical position.
2. Deceleration (T), or late swing phase, occurs after
midswing when limb is decelerating in preparation
for heel strike. Terminal swing (RLA) includes the
period from the point at which the tibia is in the
vertical position to a point just before initial contact.

GAIT TERMINOLOGIES
 Time and distances are two basic
parameters of motion.
1. Temporal variables
2. Distance variables

TEMPORAL VARIABLES
1. Stance time
2. Single limb support time
3. Double support time
4. Swing time
5. Stride time
6. Step time
7. Cadence
8. speed

DISTANCE VARIABLES
1. Stride length
2. Step length
3. Step width
4. Degree of toe out

stance time
 Amount of time spent during stance phase
of Gait cycle of one extremity.

Single support time
Amount of time that spent during the period
when only one extremity is on the supporting
surface in a gait cycle

Double support time
Amount of the time spent with both feet on
the ground during one gait cycle
 The time of double support may be
increased in elder patients and in those
having balance disorders
 The time of double support decreases when
speed of walking increases

Stride duration
 Amount of time spent in completion of one
stride or Gait cycle
 One stride duration for a normal stride is 1
second.
 Changes occur in stride length during
normal, slow, fast walking.

Stride length
 Gait cycle is also called stride
 The linear distance between heel strike of one
extremity and when the same extremity heel strike
again ( time spent in a gait cycle of one extremity)
 A stride include two steps, right and left
 Stride length greatly varies among individual
because it is effected by leg length, gender, age.
 Stride length decreases with increase in age

Step length
Linear distance between two successive points of the
opposite extremities.
 Comparison of the right and left steps provides an
indication of gait symmetry, the more equal are the
step length more symmetrical will be the gait

Step duration
The amount of time spent in completion of a
single step.
 Its measurements is expressed as sec/step
 When there is weakness or pain in an
extremity step duration may be decreased
on the effected side while increased on the
unaffected side

cadence
The number of steps taken by a person per unit time
Cadence=number of steps/sec or min
 Shorter step length will result in increase cadence at a
given velocity
 When a person is walking with cadence between 80
and 120 steps/min, then cadence and stride length
have a linear relationship

 If cadence increases the double support
time decreases and vice versa
 Normal cadence , man=110 steps/min
 Normal cadence, woman=116 steps/min

Walking velocity
 Is the rate of linear forward motion of the body in
a specific direction
 It can be measured as, cm/sec, meter/min or
miles/hour
 If the direction is not specified than term walking
velocity is called “walking speed”
Walking velocity or speed=distance walked/ time
Distance(cm, m, miles, km)
Time(sec, min, hour)

 Speed of gait may be referred as slow, free
or fast
 Free gait speed refer to person normal
walking speed
 Slow or fast speed of gait refer to slower or
faster speed than person normal walking
speed.

Step width
 Step width, or width of the
walking base
 It is measured by the linear
distance between the mid point
of the heel of one foot and the
same point of the other foot.
 Step width increases if there is
increased demand for side to
side stability.
 Normal is 5-10cm

Degree of toe out
It is the angle of foot placement(FP) and may
be found by measuring the angle formed by
each foot line of progression and a line which
intersect the center of heel and second toe.
 Normal angle = 7 degree
 Angle of toe-out decreases as the speed of
walking increases

Path of Center of Gravity
 Center of Gravity (CG):
– midway between the hips
– Few cm in front of S2
 Least energy consumption if CG travels in
straight line

A. Vertical displacement:
 Rhythmic up & down
movement
 Highest point: midstance
 Lowest point: double support
 Average displacement: 5cm
 Path: extremely smooth
sinusoidal curve

B. Lateral displacement:
 Rhythmic side-to-side
movement
 Lateral limit: midstance
 Average displacement: 5cm
 Path: extremely smooth
sinusoidal curve

Determinants of Gait
Saunder determinants
 Six optimizations used to minimize
excursion of CG in vertical & horizontal
planes
 Reduce significantly energy consumption of
ambulation
 Classic papers: Sanders, Inman (1953)

Determinants of Gait
Saunder determinants
1) Pelvic rotation
2) Pelvic tilt
3) Knee flexion in stance phase
4) Ankle mechanism
5) Foot mechanism
6) Lateral displacement of body

Determinants of Gait :
 (1) Pelvic rotation:
 Forward rotation of the pelvis in the horizontal
plane approx. 8o on the swing-phase side
 Enables a slightly longer step-length w/o further
lowering of CG

 (2) Pelvic tilt:
 5o dip of the swinging side (i.e. hip adduction)
 In standing, this dip is a positive Trendelenberg
sign

 (3) Knee flexion in stance phase:
 Approx. 20o dip
 Shortens the leg in the middle of stance phase

 (4) Ankle mechanism:
 Lengthens the leg at heel contact
 Smoothens the curve of CoG

 (5) Foot mechanism:
 Lengthens the leg at toe-off as ankle moves from
dorsiflexion to plantarflexion
 Smoothens the curve of CG

 (6) Lateral displacement of body:
 The normally narrow width of the walking base
minimizes the lateral displacement of CG

JOINT MOTIONS
 The approx. ROM needed in normal gait and the time
of occurrence of the maximum flexion/extension for
each major joint may be determined by examining the
joint angels
 These angles varies with age, gender, and walking
speed.
 Approx. values may be calculated

 Anatomical position for Hip, Knee, Ankle
are considered as 0 degree, while the
flexion for the hip, knee, and dorsiflexion of
the ankle is considered as positive values
and extension and planter flexion are given
negative values

SAGGITAL PLANE
HIP JOINT
 During stance phase hip achieve maximum
flexion(approx. +20 degree) at initial contact at
0% of the gait cycle and its most extended
position (approx. -20 degrees) at about 50% of
the gait cycle, between heel-off and toe-off
 During swing phase (mid-swing) hip joint
reaches its maximum flexion (approx. +30
degrees).

KNEE JOINT
 The knee is straight (0 degree) at initial
contact and nearly straight just before heel-
off at 40% of the gait cycle.
 During foot-flat of the gait cycle the knee
reaches it maximum flexion of (approx.
+15 degree)
 During swing phase(acceleration) the knee
reaches upto 60 degree flexion at 70% of
gait cycle

ANKEL JOINT
 The ankle reaches maximum dorsi flexion
of ( approx. +7 degree) at heel-off at 40% of
the gait cycle and reaches maximum planter
flexion( approx. -25 degrees) at toe-off 60%
of the gait cycle

JOINT MOTIONS STANCE PHASE
Sagittal Plane

JOINT MOTIONS SWING PHASE
Sagittal Plane

NORMAL WALKING
 For normal walking:
 Hip: ROM approx. 20-30 degree of flexion
and extension
 Knee: ROM, 0 degree to 60 degree of
flexion
 Ankle: ROM, 25 degree planter flexion to 7
degree dorsi flexion
*** If ROM of the above joint are not sufficient than
considerable deviation will occur from the normal gait

FRONTAL PLANE JOINT ANGLES
 During the first 20% of the stance of the gait
cycle, pelvis or the contralateral side drops about 5
degree which results in hip adduction of the
supporting limb.
 The hip abducts smoothly to 5 degree of
abduction, peaking about toe-off, then returns to
neutral at initial contact

 Knee remains more or less in neutral
position except for a brief abduction
peaking at about 7 degrees in mid swing
and then returns to neutral position
 Ankle everts from 5 degrees of inversion to
5 degree of eversion in early stance and
inverts during push-off

TRANSVERSE ANGLES
 Hip externally rotates until approx. midswing and
then internal rotates to near neutral before initial
contact.
 The knee joint remains relatively neutral through
out most of the gait cycle but external rotates in
late stance until about foot flat.
 The ankle has three rapid reversals of rotation
from about 40% of the gait cycle until initial
contact and reaches a point of maximum external
rotation at about foot flat.

STAIR GAIT
 Stair climbing is an important mode of
locomotion having many similarities to that
of level ground locomotion, the difference
between the two modes are extremely
important for the patient population.
 The muscle strength and ROM required for
locomotion on level ground does,t ensure
that the patient will be able to climb stairs.

 The trunk ROM during level ground is
similar to trunk ROM during descent but
differed from the stair gait during ascending
in all planes, trunk flexion during ascending
gait is at least double to that of trunk flexion
in descending and level ground gait.
 Gait on stair is similar to level ground
walking in that stair gait involves both
swing and stance phases, and to carry HAT.

STAIR GAIT
 The net internal movements of the hip, knee, ankle
during stair ascending and descending when compared
to level ground walking, the internal knee extensor
movement in both ascending and descending was
approx. three times larger that that of level ground.
 Ankle moments are approx. the same.
 Power generation mainly occur during ascending and
power generation absorption occur during descending

RUNNING GAIT
 Locomotion mode which is similar to walking, but
there are certain differences.
 A person able to walk on level ground may not able
to run, running requires greater balance, muscle
strength, and ROM as walking.
 Body needs greater balance as running is
characterized by reduced base due to lake of double
support and the presence of floating periods in
which both extremities are out of contact with the
ground. Presence of floating periods increases will
increase the speed of the running.

RUNNING GAIT
 Knee is flexed about 20 degree when foot strike the ground
which also increases forces on the PF joint.
 Typical base of the support is considerably less than
normal walk i.e.: 2-4inches
 Both the feet falls in the same line of progression so the
center of mass of the body must be placed over single
supported foot.
 To compensate for the reduced base of support the
functional varus angle increases. Which is the angle
between bisection of the lower leg and floor, it increases 5
degree during running

ABNORMAL GAIT
 Many causes of abnormal gait, it may be
temporary, due to sprained ankle or
permanent following stroke. Following are
the abnormal gaits based on general causes
 Muscular weakness/paralysis
 Joint muscle range-of-motion (ROM) limitation
 Neurological involvement
 Pain
 Leg length discrepancy

Muscular weakness
 Gluteus Maximus gait
 Gluteus Medius gait
 Quadriceps gait
 Hamstring gait

Types of pathological gait
 Due to pain –
– Antalgic or limping gait – (Psoatic Gait)
 Due to neurological disturbance –
– Muscular paralysis – both
»Spastic (Circumductory Gait, Scissoring
Gait, Dragging or Paralytic Gait, Robotic
Gait[Quadriplegic]) and
»Flaccid (Lurching Gait, Waddaling Gait,
Gluteus Maximus Gait, Quadriceps Gait,
Foot Drop or Stapping Gait)

Types of pathological gait
– Cerebellar dysfunction (Ataxic Gait)
– Loss of kinesthetic sensation
(Stamping Gait)
– Basal ganglia dysfunction (Festinaut
Gait)

 Due to abnormal deformities –
– Equinus gait
– Equinovarous gait
– Calcaneal gait
– Knock & bow knee gait
– Genurecurvatum gait
 Due to Leg Length Discrepancy (LLD) –
– Equinnus gait

Antalgic gait
 This is a compensatory gait pattern adopted in order
to remove or diminish the discomfort caused by pain
in the LL or pelvis.
 Characteristic features:
– Decreased in duration of stance phase of the
affected limb (unable of weight bear due to pain)
– There is a lack of weight shift laterally over the
stance limb and also to keep weight off the
involved limb
– Decrease in stance phase in affected side will
result in a decrease in swing phase of sound limb.

Psoatic gait
 Psoas bursa may be inflamed & edematous,
which cause limitation of movement due to
pain & produce a atypical gait.
– Hip externally rotated
– Hip adducted
– Knee in slight flexion
 This process seems to relieve tension of the
muscle & hence relieve the inflamed
structures.

Gluteus maximus gait
 The gluteus maximus act as a restraint for
forward progression.
 The trunk quickly shifts posteriorly at heel
strike (initial contact).
 This will shift the body’s COG posteriorly
over the gluteus maximus, moving the line
of force posterior to the hip joints.

Cont ……
 With foot in contact with floor, this requires
less muscle strength to maintain the hip in
extension during stance phase.
 This shifting is referred to as a “Rocking
Horse Gait” because of the extreme
backward-forward movement of the trunk.

Gluteus medius gait
 It is also known as “Trendelenberg gait” or
“Lurching Gait” when one side affected.
 The individual shifts the trunk over the
affected side during stance phase.
 When right gluteus medius or hip abductor is
weak it cause Right side of the pelvis drop
when the right leg leaves the ground & begins
swing phase.

Cont …..
 Shifting the trunk over the affected side is an
attempt to reduce the amount of strength
required of the gluteus medius to stabilize the
pelvis.
 Bilateral paralysis, waddling or duck gait.
 The patient lurch to both sides while walking.
 The body sways from side to side on a wide
base with excessive shoulder swing.
– E.g. Muscular dystrophy

Quadriceps gait
 Quadriceps action is needed during heel
strike & foot flat when there is a flexion
movement acting at the knee.
 Quadriceps weakness/ paralysis will lead to
buckling of the knee during gait & thus loss
of balance.
 Patient can compensate this if he has normal
hip extensor & plantar flexors.

 Compensation:
– With quadriceps weakness, the individual may
lean forward over the quadriceps at the early
part of stance phase, as weight is being shifted
on to the stance leg.
– Normally, the line of force falls behind the
knee, requiring quadriceps action to keep the
knee from buckling.
– By leaning forward at the hip, the COG is
shifted forward & the line of force now falls in
front of the knee.

Cont …
– This will force the knee backward into
extension.
 Another compensatory manoeuvre to use is the hip
extensors & ankle plantar flexors in a closed chain
action to pull the knee into extension at heel strike
(initial contact).
 In addition, the person may physically push on the
anterior thigh during stance phase, holding the knee
in extension.

Genu recurvatum gait or
Hamstring Gait
 Quadriceps paralysis, Hamstrings are
weak or planter flexors contracture,
– During stance phase, the knee will go
into excessive hyperextension, referred
to as “genu recurvatum” gait.
– If only hamstrings are weak
– During the deceleration (terminal
swing) part of swing phase, without the
hamstrings to slow down the swing
forward of the lower leg, the knee will
snap into extension.

Hemiplegic gait
 With spastic pattern of hemiplegic leg
– Hip into extension, adduction &
medial rotation
– Knee in extension, though often
unstable
– Ankle in drop foot with ankle plantar
flexion and inversion (equinovarus),
which is present during both stance
and swing phases.
 In order to clear the foot from the ground
the hip & knee should flex.

 But the spastic muscles won’t allow the hip & knee
to flex for the floor clearance.
 So the patient hikes hip & bring the affected leg by
making a half circle i.e. circumducting the leg.
 Hence the gait is known as “Circumductory Gait”.
 Usually, there will be no reciprocal arm swing.
 Step length tends to be lengthened on the involved
side & shortened on the uninvolved side.

Scissoring gait
 It results from spasticity of
bilateral adductor muscle of
hip.
 One leg crosses directly over
the other with each step like
crossing the blades of a
scissor.
– E.g. Cerebral Palsy

Dragging or paraplegic gait
 There is spasticity of both hip & knee
extensors & ankle plantar flexors.
 In order to clear the ground the patient has
to drag his both lower limb swings them &
place it forward.

Cerebral Ataxic or Drunkard’s
gait
 Abnormal function of cerebellum result in a
disturbance of normal mechanism
controlling balance & therefore patient
walks with wider BOS.
 The wider BOS creates a larger side to side
deviation of COG.
 This result in irregularly swinging sideways
to a tendency to fall with each steps.
 Hence it is known as “Reeling Gait”.

Sensory ataxic gait
 This is a typical gait pattern seen in patients
affected by tabes dorsalis.
 It is a degenerative disease affecting the
posterior horn cells & posterior column of
the spinal cord.
 Because of lesion, the proprioceptive
impulse won’t reach the cerebellum.
 The patient will loss his joint sense &
position for his limb on space.

 Because of loss of joint sense, the patient
abnormally raises his leg (high step) jerks it
forward to strike the ground with a stamp.
 So it is also called as “Stamping Gait”.
 The patient compensated this loss of joint
position sense by vision.
 So his head will be down while he is
walking.

Short shuffling or festinate gait
or Parkinsonian Gait
 Normal function at basal ganglia are:
– Control of muscle tone
– Planning & programming of normal movements.
– Control of associated movements like reciprocal
arm swing.
– Typical example for basal ganglia lesion is
parkinsonism.

Parkinsonian Gait
 In this gait, the patient will have rigidity and
bradykinesia.
 He or she will be stooped with the head and
neck forward, with flexion at the knees.
 The whole upper extremity is also in flexion
with the fingers usually extended.
 The patient walks with slow little steps.
 Patient may also have difficulty initiating
steps.

 This posture displaces the COG anteriorly.
 So in order to keep the COG within the
BOS, the patient will take no of small
shuffling steps.
 Due to loss of voluntary control over the
movement, they loses balance & walks
faster as if he is chasing the COG.
 So it is called as “Festinate Gait”.
 Since his shuffling steps, it is otherwise
called as “Shuffling Gait”.

Foot drop or slapping gait
 This is due to dorsiflexor weakness caused
by paralysis of common peroneal nerve.
 There won’t be normal heel strike, instead
the foot comes in contact with ground as a
whole with a slapping sound.
 So it is also known as “Slapping gait”.

Cont ….
 Due to plantarflexion of the ankle, there
will be relatively lengthening at the leading
extremity.
 So to clear the ground the patient lift the
limb too high.
 Hence the gait get s its another name i.e.
“High Stepping Gait”

Equinus gait
 Equinus = Horse
 Because of paralysis of dorsiflexor which
result in plantar flexor contracture.
 The patients will walk on his toes (toe
walking).
 Other cause may be compensation by
plantar flexor for a short leg.

Unequal Leg Length
 We all have unequal leg length, usually a
discrepancy of approx 1/4 inch between the
right and left legs.
 Clinically, these smaller discrepancies are
often corrected by inserting heel lifts of
various thicknesses into the shoe.

 Leg length discrepancy (LLD) are divided
in –
– Minimal leg length discrepancy
– Moderate leg length discrepancy
– Severe leg length discrepancy

Minimal LLD
 Compensation occurs by dropping the
pelvis on the affected side.
 The person may compensate by leaning
over shorter leg (up to 3 inches can be
accommodated with these tech).

Moderate LLD
 Approx between 3 & 5 cm, dropping the
pelvis on the affected side will no longer be
effective.
 A longer leg is needed, so the person
usually walks on the ball of the foot on the
involved (shorter) side.
 This is called an “Equinnus Gait”.

Severe LLD
 It is usually discrepancy of more than 5 inches.
 The person may compensate in a variety of
ways.
 Dropping the pelvis and walking in an
equinnus gait plus flexing the knee on the
uninvolved side is often used.
 To gain an appreciation for how this may feel
or look, walk down the street with one leg in
the street and the other on the sidewalk.

Equinovarous gait
 There will be ankle plantar flexion &
subtalar inversion.
 So the patient will be walking on the outer
border of the foot.
– E.g. CETV

Calcaneal gait
 Result from paralysis plantar flexors causing
dorsiflexor contracture.
 The patient will be walking on his heel (heel
walking)
 It is characterized by greater amounts of ankle
dorsiflexion & knee flexion during stance & a
shorter step length on the affected side.
 Single-limb support duration is shortened because
of the difficulty of stabilizing the tibia & the knee.

Knock knee gait
 It is also known as genu valgum gait.
 Due to decreased physiological valgus of
knee.
 Both the knee face each other widening the
BOS.

Bow leg gait
 It is also known as genu varum gait.
 Knee face outwards.
 Due to increase increased physiological
valgus of knee.
 The legs will be in a bowed position.

JOINT/ MUSCLE ROM
LIMITATION
 Hip flexion contracture
 Fused hip joint
 Knee flexion contracture
 Knee joint fusion
 Ankle fusion

Human Gait

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