Biomechanics, Analysis, and Abnormalities in Gait. Oriented for Second-year students of Undergraduate Physiotherapy studies. Details of kinetic and kinematic analysis of gait.

1. Biomechanics of the
Gait
Dr. Vivek H. Ramanandi (PT)
MPT (Neuro), Ph. D. Scholar,
Sr. Lecturer,
Satish Goswami College of Physiotherapy,
Ahmedabad.

2. Introduction
 In human locomotion (ambulation, gait),
we discover how individual joints and
muscles function in an integrated
manner both to maintain upright posture
and to produce motion of the body as a
whole.
 Knowledge of the kinematics and
kinetics of normal ambulation provides
the reader with a foundation for
analyzing, identifying, and correcting
abnormalities in gait.
2

3.  Human locomotion, or gait, may be
described as a translatory
progression of the body as a whole,
produced by coordinated, rotatory
movements of body segments.
 The alternating movements of the
lower extremities essentially support
and carry along the head, arms, and
trunk (HAT).
3

4.  HAT constitutes about 75% of total body
weight, with the head and arms contributing
about 25% of total body weight and the
trunk contributing the remaining 50%.
 Walking is probably the most
comprehensively studied of all human
movements, and the variety of
technologies, coupled with the diversity of
disciplinary perspectives, has produced a
complex and sometimes daunting literature.
4

5.  Nevertheless, the biomechanical
requirements of the movement that
explain gait are logical and easily
understood if the detail is not permitted
to cloud comprehension.
 The purpose of this discussion is to
provide this comprehension of gait that
will serve as the foundation for analysis
of normal walking and of gait deviations.
5

6. General Features
 In early gait analysis, investigators used
cinematographic film.
 Until about 20 years ago, sophisticated
analysis required frame-by-frame hand-
digitizing of markers that had been placed
on body landmarks.
 These data were coupled with knowledge of
the center of pressure (CoP) of the foot-
floor forces derived from a force platform to
give complete, if simplified, kinetic
information.
 This is referred to as the inverse dynamic
approach with link segment mechanics.
6

7.  Electrogoniometers fastened to
joints were also commonly used to
describe joint motion and still have
applications.4
 Similarly, electromyography (EMG)
has been used for many decades,
although the expectation that it would
be possible to convert those signals to
force values in simple, useful ways
7

8.  The past two decades have witnessed an
explosion of technical advancements in
motion analysis whose greatest virtue is the
ability to collect and process large amounts of
data.
 As with the development of any science, the
knowledge available far exceeds its current
applications.
 A modern gait laboratory (Fig. 14-1) includes
some kind of motion analysis system that
gives precise marker locations that are
subsequently used to model a several-
segment body with joint centers and centers
of mass. 8

9. 9

10.  One or more force platforms provide
simultaneous foot-floor forces.
 EMG systems provide simultaneous
information from surface or, sometimes,
indwelling electrodes.
 An excellent and engaging report of the
evolution of clinical gait analysis,
including motion analysis and EMG, can
be found in Sutherland’s articles.
10

11.  To understand gait, let us first identify the
fundamental purposes.
 Winter proposed the following five main tasks for
walking gait:
1. maintenance of support of the HAT: that is,
preventing collapse of the lower limb
2. maintenance of upright posture and balance of the
body
3. control of the foot trajectory to achieve safe ground
clearance and a gentle heel or toe landing
4. generation of mechanical energy to maintain the
present forward velocity or to increase the forward
velocity
5. absorption of mechanical energy for shock
absorption and stability or to decrease the forward 11

12.  The professional staff at Rancho Los
Amigos National Rehabilitation Center
in California identified three main
tasks in walking:
◦ (1) weight acceptance (WA),
◦ (2) single-limb support, and
◦ (3) swing limb advancement.
 Although worded differently, these
concepts correspond to Winter’s first
three tasks.
12

13.  However, the body moves only because
energy is generated by means of
concentric contraction of muscle groups.
 In fact, normal walking at a constant
velocity requires small bursts of energy
from three muscle groups at two
important times in the gait cycle.
 Likewise, unless energy is removed with
each step through eccentric muscle
contractions, the velocity of walking
would continue to increase.
13

14. Gait Initiation
 Gait initiation may be defined as a
stereotyped activity that includes the
series or sequence of events that occur
from the initiation of movement to the
beginning of the gait cycle.
 Gait initiation begins in the erect
standing posture with an activation of the
tibialis anterior and vastus lateralis
muscles, in conjunction with an inhibition
of the gastrocnemius muscle.
14

15.  Bilateral concentric contractions of the tibialis anterior
muscle (pulling on the tibias) results in a sagittal torque
that inclines the body anteriorly from the ankles.
 Initially, the CoP is described as shifting either
posteriorly and laterally toward the swing foot (foot that
is preparing to take the first step) or posteriorly and
medially toward the supporting limb.
 Abduction of the swing hip occurs almost
simultaneously with contractions of the tibialis anterior
and vastus lateralis muscles and produces a coronal
torque that propels the body toward the support limb.
15

16.  According to Elble and colleagues, the
support limb hip and knee flex a few
degrees (3 to 10), and the CoP moves
anteriorly and medially toward the
support limb.
 This anterior and medial shift of the CoP
frees the swing limb so that it can leave
the ground.
 The gait initiation activity ends when
either the stepping or swing extremity
lifts off the ground or when the heel
strikes the ground. 16

17.  The total duration of the gait initiation
phase is about 0.64 second.
 A healthy individual may initiate gait
with either the right or left lower
extremity, and no changes will be
seen in the pattern of events.
17

18. 18

19. Phases of the Gait Cycle
 Gait has been divided into a number of
segments that make it possible to describe,
understand, and analyze the events that are
occurring.
 A gait cycle spans two successive events of
the same limb, usually initial contact (also
called heel contact or heel strike) of the lower
extremity with the supporting surface.
19

20. 20

21.  During one gait cycle, each extremity
passes through two major phases:
◦ a stance phase, when some part of the foot is in
contact with the floor, which makes up about
60% of the gait cycle, and
◦ a swing phase, when the foot is not in contact
with the floor, which makes up the remaining
40%
21

22.  There are two periods of double support occurring
between the time one limb makes initial contact and the
other one leaves the floor at toe-off.
 At a normal walking speed, each period of double
support occupies about 11% of the gait cycle, which
makes a total of approximately 22% for a full cycle.
 The body is thus supported by only one limb for nearly
80% of the cycle. The approximate value of 10% for
each double-support phase is usually used.
 The approximate value of 10% for each double-support
phase is usually assigned to each of the two double-
support periods.
22

23. 23

24.  The two most common terminologies for
the further division of these major
phases into sub phases are shown in
Figures 14-3 and 14-4,
where one will be referred to as
traditional (T),
and one derived from Rancho Los
Amigos (RLA).
 Both terminologies define “events” that
mark the start and end of defined sub-
phases.
24

25.  Figure 14-3 identifies the events
delimiting the major phases in both
terminology conventions as initial contact
(T and RLA) or heel contact or heel
strike (T) and toe-off (RLA and T).
 In both conventions, the gait cycle is
divided into percentiles that will be used
to clarify events and phases.
 Values for normal walking appear in the
figures.
25

26. 26

27. Events in Stance Phase
 1. Heel contact or heel strike (T) refers to the
instant at which the heel of the leading extremity
strikes the ground (Fig. 14-5).
 The word “strike” is actually a misnomer
inasmuch as the horizontal velocity reduces to
about 0.4 m/sec and only 0.05 m/sec vertically
 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.
27

28. 28

29. 2. Foot flat (T) in normal gait occurs
after initial contact at approximately
7% of the gait cycle (Fig. 14-6).
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 (Fig. 14-7),
usually about 30% of the gait cycle.
29

30. 30

31. 31

32. 4. Heel-off (T) is the point at which the
heel of the reference extremity leaves
the ground (Fig. 14-8), usually about
40% of the gait cycle.
5. Toe-off (T and RLA) is the instant at
which the toe of the foot leaves the
ground (Fig. 14-9), usually about 60%
of the gait cycle.
32

33. 33

34. 34

35. Subphases of Stance Phase
1. Heel strike phase (T) begins with initial
contact and ends with foot flat and
occupies only a small percentage of the
gait cycle (see Fig. 14-3).
2. Loading response (RLA), or WA, begins
at initial contact and ends when the
contralateral extremity lifts off the ground
at the end of the double-support phase
and occupies about 11% of the gait cycle
(see Fig. 14-3).
35

36. 3. Midstance phase (T) begins with foot
flat at 7% of the gait cycle and ends with
heel-off at about 40% of the gait cycle.
Midstance phase (RLA) begins when the
contralateral extremity lifts off the ground
at about 11% of the gait cycle and ends
when the body is directly over the
supporting limb at about 30% of the gait
cycle,
which makes it a much smaller portion of
stance phase than the T midstance
phase. 36

37. 4. Terminal stance (RLA) begins when the body is
directly over the supporting limb at about 30% of
the gait cycle and ends a point just before initial
contact of the contralateral extremity at about
50% of the gait cycle.
5. Push-off phase (T) begins with heel-off at about
40% of the gait cycle and ends with toe-off at
about 60% of the gait cycle (see Fig. 14-2).
6. Preswing (RLA) is the last 10% of stance phase
and begins with initial contact of the contralateral
foot (at 50% of the gait cycle) and ends with toe-
off (at 60%).
37

38. Swing Phase
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
(see Fig. 14-3).
2. Initial swing (RLA) begins when the
toe leaves the ground and continues
until maximum knee flexion occurs.
38

39. 3. 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.
39

40. 4. 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.
40

41.  For most purposes, including patient
report writing, it is preferable to refer to
events as occurring in early, middle, or
late stance phase or in early, middle, or
late swing phase.
 For detailed description or quantitative
analysis, more specific events and
phases may be needed,
but it is most important that the student
grasp the overall picture and understand
the major events of gait,
which can become buried in excessive
terminology.
41

42. Gait Terminology
 Time and distance are two basic
parameters of motion, and
measurements of these variables
provide a basic description of gait.
 Temporal variables include
◦ stance time,
◦ single-limb and double-support time,
◦ swing time,
◦ stride and step time,
◦ cadence, and
◦ speed.
42

43.  The distance variables include
◦ stride length,
◦ step length and width, and
◦ degree of toe-out.
 These variables, derived in classic
research of over 30 years ago, provide
essential quantitative information
about a person’s gait and should be
included in any gait description
43

44.  Each variable may be affected by such
factors as
◦ age,
◦ sex,
◦ height,
◦ size and shape of bony components,
◦ distribution of mass in body segments,
◦ joint mobility,
◦ muscle strength,
◦ type of clothing and footgear,
◦ habit, and
◦ psychological status
44

45.  Stance time is the amount of time that
elapses during the stance phase of
one extremity in a gait cycle.
 Single-support time is the amount of
time that elapses during the period
when only one extremity is on the
supporting surface in a gait cycle
45

46.  Double-support time is the amount of
time spent with both feet on the
ground during one gait cycle.
 The percentage of time spent in
double support may be increased in
elderly persons and in those with
balance disorders.
 The percentage of time spent in
double support decreases as the
speed of walking increases.
46

47.  Stride length is the linear distance
between two successive events that
are accomplished by the same lower
extremity during gait.
 In general, stride length is determined
by measuring the linear distance from
the point of one heel strike of one
lower extremity to the point of the next
heel strike of the same extremity (Fig.
14-10).
47

48. 48

49.  The length of one stride is traveled
during one gait cycle and includes all
of the events of one gait cycle.
 Stride length also may be measured
by using other events of the same
extremity, such as toe-off, but in
normal gait, two successive heel
strikes are usually used
49

50.  A stride includes two steps, a right
step and a left step.
 However, stride length is not always
twice the length of a single step,
because right and left steps may be
unequal.
 Stride length varies greatly among
individuals, because it is affected by
leg length, height, age, sex, and other
variables.
50

51.  Stride length usually decreases in elderly
persons and increases as the speed of
gait increases.
 The length of one stride is traveled
during one gait cycle
 Stride duration refers to the amount of
time it takes to accomplish one stride.
 Stride duration and gait cycle duration
are synonymous.
 One stride, for a normal adult, lasts
approximately 1 second.
51

52.  Step length is the linear distance
between two successive points of
contact of opposite extremities.
 It is usually measured from the heel
strike of one extremity to the heel strike
of the opposite extremity (see Fig. 14-
10).
 A comparison of right and left step
lengths will provide an indication of gait
symmetry
 The more equal the step lengths, the
more symmetrical is the gait. 52

53.  Step duration refers to the amount of
time spent during a single step.
 Measurement usually is expressed as
seconds per step.
 When there is weakness or pain in an
extremity, step duration may be
decreased on the affected side and
increased on the unaffected (stronger)
or less painful side
53

54.  Cadence is the number of steps taken
by a person per unit of time.
 Cadence may be measured as the
number of steps per second or per
minute, but the latter is more common:
Cadence = number of steps/time
54

55.  A shorter step length will result in an
increased cadence at any given velocity.
 Lamoreaux found that when a person
walks with a cadence between 80 and
120 steps per minute, cadence and
stride length had a linear relationship.
 As a person walks with increased
cadence, the duration of the double-
support period decreases.
 When the cadence of walking
approaches 180 steps per minute, the
period of double support disappears, and
running commences.
55

56.  A step frequency or cadence of about
110 steps per minute can be
considered as “typical” for adult men;
a typical cadence for women is about
116 steps per minute.
56

57.  Walking velocity is the rate of linear
forward motion of the body, which can be
measured in meters or centimeters per
second, meters per minute, or miles per
hour.
 Scientific literature favors meters per
second.
 In instrumented gait analyses, walking
velocity is used, inasmuch as the
velocities of the segments involve
specification of direction:
Walking velocity (meters/second) =
distance walked (meters)/time (seconds)
57

58.  Women tend to walk with shorter and
faster steps than do men at the same
velocity.
 Increases in velocity up to 120 steps
per minute are brought about by
increases in both cadence and stride
length, but above 120 steps per
minute, step length levels off, and
speed increases are achieved with
only cadence increases.
58

59.  Speed of gait may be referred to as slow,
free, and fast.
 Free speed of gait refers to a person’s
normal walking speed; slow and fast
speeds of gait refer to speeds slower or
faster than the person’s normal
comfortable walking speed, designated
in a variety of ways.
 There is a certain amount of variability in
the way an individual elects to increase
walking speed
59

60.  Some individuals increase stride
length and decrease cadence to
achieve a fast walking speed.
 Other individuals decrease the stride
length and increase cadence.
60

61.  Step width , or width of the walking
base, may be found by measuring the
linear distance between the midpoint
of the heel of one foot and the same
point on the other foot (see Fig. 14-
10).
 Step width has been found to increase
when there is an increased demand
for side-to-side stability, such as
occurs in elderly persons and in small
children. 61

62.  In toddlers and young children, the
center of gravity is higher than in
adults, and a wide base of support is
necessary for stability.
 In the normal population, the mean
width of the base of support is about
3.5 inches and varies within a range of
1 to 5 inches
62

63.  Degree of toe-out represents the angle
of foot placement (FP) and may be found
by measuring the angle formed by each
foot’s line of progression and a line
intersecting the center of the heel and
the second toe.
 The angle for men normally is about 7°
from the line of progression of each foot
at free speed walking (see Fig. 14-10).
 The degree of toe-out decreases as the
speed of walking increases in normal
men.
63

64. Positive & Negative Muscle Work
During Gait
 Power generation is accomplished
when muscles shorten (concentric
contraction).
 They do positive work and add to the
total energy of the body.
 Power is the work or energy value
divided by the time over which it is
generated.
64

65.  The power of muscle groups
performing gait is calculated through
an inverse dynamic approach.
 The power generated or absorbed
across a joint is the product of the net
internal moment and the net angular
velocity across the joint.
65

66.  If both are in the same direction
(flexors flexing, extensors extending,
for example), positive work is being
accomplished by energy generation.
 The most important phases of power
generation and absorption have been
designated by joint (H= hip, K = knee,
A= ankle) and plane (S = sagittal, F=
frontal, T= transverse).
66

67.  Power absorption is accomplished
when muscles perform a lengthening
(eccentric) contraction.
 They do negative work and reduce the
energy of the body.
 If joint motion and moment are in
opposite directions, negative work is
being performed through energy
absorption.
67

68. Determinants of Gait
 First described by Saunders and
coworkers in 1953 and elaborated on by
Inman & colleagues in 1981.
 The determinants are supposed to
represent adjustment made by the
pelvis, hips, knees, and ankles that help
to keep movement of the body’s COG to
a minimum.
 The determinants are credited with
decreasing the vertical and lateral
excursions of the body’s COG and
therefore decreasing energy expenditure
and making gait more efficient
68

69.  The vertical displacement of the
body’s COG produces a smooth
sinusoidal curve in normal walking.
 The lowest point in the curve is during
the period of double support.
 The highest point in the curve
coincides with midstance when the
trunk is directly over the stance
extremity.
 The drawing shows the lowest and
highest points in the curve.
69

70. 70
The vertical displacement of the body’s COG

71.  Lateral displacement of CG
 Rhythmic side to side movement
 Average displacement is 5 cm
 Path is smooth sinusoidal curve type
71

72. 72

73.  The determinants are:
◦ Lateral pelvic tilt in the frontal plane,
◦ Knee flexion during stance,
◦ Knee interactions,
◦ Pelvic rotation in the transverse plane and,
◦ Physiological valgus of the knee
 The order of presentation of the
determinants that follows is based on
their function and is not necessarily
related to the order in which they appear
in the gait 73

74. 74

75.  The first 4 determinants are supposed
to help to keep the vertical rise of the
body’s COG to a minimum.
 The 5th determinant prevents a drop in
the body’s COG, and
 the 6th determinant reduces the side to
side movement of the COG
75

76. Lateral Pelvic Tilt (Pelvic Drop
in the Frontal Plane
 In single limb support the combined
weight of HAT and the swinging leg must
be balanced over one extremity.
 During this period the COG reaches its
highest point in the sinusoidal curve.
 Lateral tilting of the pelvis (pelvic drop)
on the side of the unsupported extremity
(swing leg) keeps the peak of the rise
lower than if the pelvis did not drop,
because the drop produces a relative
adduction of the stance hip in the stance
phase and relative abduction of the
swinging extremity
76

77. Lateral pelvic tilt in the frontal plane
keeps the peak of the sinusoidal curve lower
77

78.  The tilting of pelvis is
controlled by the hip
abductor muscles of
the stance extremity.
 For example, pelvic
drop on the side of
the right swing
extremity is
controlled by
isometric and
eccentric
contractions of the
left hip abductor
muscles 78

79. Knee Flexion
 Knee flexion at midstance when COG is at
its highest represents another adjustment
that helps to keep the COG from rising as
much as it would have to if the body had to
pass over a completely extended knee
79

80. Knee, Ankle, and Foot
Interactions
 Movements at the knee occur in
conjunction with movements at the
ankle and foot and are responsible for
smoothing the pathways of the body’s
COG so that it forms a sinusoidal
curve.
 Combined knee, ankle, and foot
movements prevent abrupt changes in
the vertical displacement of the body’s
from a downward to an upward
direction 80

81. 81

82.  The change from a downward motion of
the COG at heel strike to an upward
motion at foot flat (loading response) is
accomplished by knee flexion, ankle
plantarflexion, and foot pronation.
 These combined motions serve to
relatively shorten the extremity and thus
prevent an abrupt rise in the body’s COG
after heel strike.
 If these motions did not occur in
conjunction with each other, the COG
would rise abruptly after heel strike as
the tibia rides over talus
82

83.  Another stage of stance in which knee
ankle and foot interactions play an
important role is when the body’s
COG falls after midstance.
 A combination of ankle plantarflexion,
foot supination, and knee extension at
heel off slow the descent of the body’s
COG by a relative lengthening of the
stance extremity
83

84. Pelvic rotation in the
transverse plane
 Forward and Backward Rotation of
the Pelvis in the transverse plane
accompany forward and backward
movements of the lower extremities
during gait
 Forward rotation occurs on the side of
the swinging extremity with the hip
joint of the weight-bearing extremity
serving as the axis for pelvic rotation.
84

85.  The drawing shows right forward rotation of the
pelvis on the side of the swinging extremity. The
left hip joint serves as the axis of motion
 The pelvic rotation relatively lengthens the
extremities and therefore minimizes the drop of
body’s COG that occurs at double support
85

86.  The pelvis begins to move forward at
preswing and continues as the swinging
extremity moves forward during initial
swing.
 At the point of maximal elevation of the
body’s COG in midstance, the forward
pelvic rotation has brought the pelvis to a
neutral position with respect to rotation.
 Forward rotation of the pelvis continues
beyond neutral on the swing side
through terminal swing to initial contact
86

87.  The total amount of rotation of the pelvis
is small and averages about 4° on the
swing and stance sides for a total of 8°.
 The result of pelvic rotation is an
apparent lengthening of the lower
extremities.
 The swinging lower extremity is
lengthened in terminal swing by the
forwardly rotating pelvis, and the weight
bearing extremity is lengthened in
preswing by the posterior position of the
pelvis
87

88. 88

89. Physiological Valgus at the
Knee
 The physiologic valgus at the knee
reduces the width of the BOS from
what it would be if the femoral and
tibial shafts formed a vertical line from
the greater tuberosity of the femur
(Fig. 14-25).
 Therefore, because the BOS is
relatively narrow, little lateral motion of
the pelvis is necessary to shift the
COG from one lower extremity to
another over the BOS.
89

90. 90

91. KINEMATICS
AND
KINETICS OF GAIT
 Path of Center of Gravity
 midway between the hips
 Few cm in front of S2
 Least energy consumption if CG
travels in straight line
91

92. HEEL STRIKE TO FOOT FLAT:
 Heel strike to forefoot
loading
 Foot pronates at subtalar
joint
 Only time (stance phase)
normal pronation occurs
 This absorbs shock &
adapts foot to uneven
surfaces
 Ground reaction forces
peak
 Leg is internally rotating
 Ends with metatarsal
heads contacting ground 92

93. Sagittal plane analysis
93
Joint Motion GRF Moment Muscle Contractio
n
Hip Flexion
30-25
Anterior flexion G.Maximus
Hamstring
Add.magnu
s
Isometric to
eccentric
Knee Flexion
0-15
Anterior To
Posterior
Extension to
flexion
quadriceps Concentric
to eccentric
Ankle Plantar-
Flexion
0-15
Posterior PF Tibialis
anterior
Ex.
digitorum
longus
Ex.hallucis
longus
eccentric

94. Frontal plane analysis
JOINT MOTION
Pelvis Forwardly rotated position
Hip Medial rotation of femur on pelvis
knee Valgus thrust with increasing valgus Medial rotation
of tibia
Ankle Increase pronation
Thorax posterior position at leading ipsilateral side
Shoulder slightly behind the hip at ipsilateral extremity side
94

95. FOOT FLAT TO MIDSTANCE:
SAGIT TAL PLANE
95
Joint Motion GRF Moment Muscle Contraction
Hip Extension 25-0
Flexion-0
Anterior to
posterior
Flexion to
extension
G.maximus Concentric to
no activity
Knee Extension 15-5
flexion 5-5
Posterior to
anterior
Flexion to
extension
Quadriceps Concentric to
no activity
Ankle 15 of PF to 5-10
of DF
Posterior to
anterior
PF to DF Soleus,
gastronemiu
s, PF
Eccentric

96. Frontal plane analysis
96
Joint Motion
Pelvis Ipsilateral side rotating backward to reach neutral at midstance
,lateral tilting towards the swinging extremity
Hip Medial rotation of femur on the pelvis continue to neutral position
at midstance. Adduction moment continue throughout single
support
Knee There is reduction in valgus thrust and the tibia begins to rotate
laterally
Ankle The foot begins to move in the direction of supination from its
pronated position at the end of loading response. The foot
reaches a neutral position at midstance .
Thorax Ipsilateral side moving forward to neutral
Shoulder Moving forward

97. MIDSTANCE TO HEEL OFF
97
Join
t
Motion GRF Moment Muscle Contractio
n
Hip Extension 0 to
hyperextension of
10-20
Posterior Extension Hip flexors Eccentric
Knee Extension 5 degree
of flexion to 0
degree
Posterior
to anterior
Flexion to
extension
No activity
Ankle PF:5 degree of DF
to 0 degree
Anterior DF Soleus, PF Eccentric to
concentric
Toes Extension: o-30
degree of
hyperextens-ion
Flexor hallicus
longus and
brevis ,
Abductor digiti
quinti,
interossei,
lumbricals
SAGIT TAL PLANE

98. 98

99. 99

100. 100