2. Definition
Locomotion or gait –
Gait is the medical term to describe human locomotion
or the way that we walk.
Thus, it is a locomotion achieved through the movement
of limbs.
Different gait patterns are characterized by differences in
limb movement patterns. Thus, every individual has a
unique gait pattern, while there are some features in a
person’s gait that are common for everyone.
There are many types of gait such walking, crawling,
jogging, running and skipping.
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3. GAIT ANALYSIS AND
RECOGNITION
Under forensic science, gait is studied through forensic gait
analysis which includes the identification of gait features and
patterns of subjects seen on CCTV and from footprints forming
a gait pattern left at the scene of a crime.
The height of an individual can be determined by his/her
footprint and shoe print, as the foot tends to be approximately
15 % of the person’s average height.
Footprints are left at the scene of a crime forming a
recognizable gait cycle.
The most studied gait features since 1970s is the lower limb, as
the leg motion can be effectively used as a cue to identify a
person.
Gait recognition techniques :
Automatic analysis of Video Imagery
Radar System 3
4. Gait IDENTIFICATION
Gait pattern is identified from the
Direction line,
Walk line,
Foot line,
Foot angle,
Step angle,
Step length,
Step time,
Stride length,
Stance and Swing phase,
Cadence,
Velocity,
Width of the steps;
and other special features of the foot or footwear, in addition to usual
wear and tear of the footwear (numerous creases, flatfoot character,
horizontal & vertical ridges, corns, deformities.) 4
5. Gait CYCLE
Gait cycle is used to describe the complex activity of
walking, by describing the motions from the period of
time from one heel strike on the ground to the next
strike of the same heel, on the ground for a second time.
PHASES OF GAIT –
Gait cycle is divided into two phases :
Stance : Defined as the interval in which the foot is
on the ground (60 % of the gait cycle.)
Swing : Defined as the interval in which the foot is
not in contact with the ground (40% of the gait
cycle.)
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6. Stance phase
It begins at the instant that one extremity
contacts the ground & continuous only as long
as some portion of the foot is in contact with
the ground.
It is approx 60% of normal gait duration.
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7. Swing phase
It begins as soon as the toe of one extremity
leaves the ground & ceases just before heel
strike or contact of the same extremity.
It makes up 40% of normal gait cycle.
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8. Double support
It is the period of time when both feet are in contact with the
ground.
This occurs twice in the gait cycle – at the beginning and end
of stance phase – and also is referred to as initial and terminal
double limb stance.
It accounts to approximately 25% of gait cycle.
This phase is absent in running
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SINGLE support
It is the period of time when only one foot is in contact with the ground.
In walking, this is equal to the swing phase of the other limb.
13. PECULIAR FEATURES
It is sometimes required to determine whether a person was walking,
running or standing.
A running man exerts about 2-3 times the pressure he exert in his walk,
therefore, the shapes and sizes of the marks and the step length vary.
Step length in a slow walk is about 60 cms while it increases to about
90 cms in running.
It also varies from man to man according to his height and habits.
A standing man gives clear mark of his foot or footwear – There are
drag or slippage marks if he is walking or running.
If an individual has stood for sometime at a particular place, the marks
at the spot are found somewhat damaged.
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14. factors affecting variables
Age,
Gender,
Height,
Size & shape of bony
components,
Distribution of mass in
body segments,
Joint mobility,
Muscle strength,
Type of clothing &
footwear,
Habit,
Psychological status.
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15. Saunders’ Determinants of gait
Gait “determinants” was first described by “Saunders &
Coworkers” in 1953.
The “determinants” represent adjustments made by the
pelvis, hips, knees, foot and ankles affect energy
expenditure and the mechanical efficiency of walking.
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16. GAIT ABNORMALITY
It is a deviation from normal walking.
There are numerous causes of abnormal gait.
There can be great variation depending upon the
severity of the problem.
If a muscle is weak, how weak is it?
If joint motion is limited, how limited is it?
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17. VALUE OF GAIT EVIDENCE
If a crime had happened in a village where
there were no CCTV cameras or anything,
gait evidence can be used by taking cue
from the footprints left at the crime scene.
Any conviction cannot be given on the basis
of gait alone; it has to be corroborated by
other evidences.
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18. PRITAM SINGH and Anr.
V.
STATE OF PUNJAB
AIR 1956 SC 415
Case of murder; accused fled away; tracks found; identity of one established by looking
at his gait pattern.
Accused made to walk with four other men for the identification of foot prints.
Accused walked with a distinct limp; very much less marked on previous occasions.
The evidence of the trackers sufficiently established that one of the culprits made
footprints which showed that his way of walking was outwards and he put his right foot
more outwards than the left.
Thus, the limp in the gait had created impressions which were particularly characteristic
of this accused and went onto corroborating the story of prosecution that the tracks
obtained from crime spot was of the accused.
This was also demonstrated by the impressions which the accused made when he
walked in the District Jail with the shoes given to him there on the sandy patch, which
was specially prepare for that purpose.
His identify was thus established as the culprit, using the track evidence.
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19. Reference
Sharma, B.R., ‘Forensic Science in Criminal Investigation and Trials.’
4th Ed, Universal Law Publishing, New Delhi.
Vij, Krishan., ‘Textbook of Forensic Medicine & Toxicology.’ 4th Ed.
Elsevier Publications.
Modi., ‘Medical Jurisprudence & Toxicology.’ Lexis Nexis,
Buttersworth (2010)
http://en.wikipedia.org/wiki/Gait_%28human%29
http://www.active.com/running/articles/what-is-a-gait-analysis
http://www.sportsinjuryclinic.net/sports-specific/running-injuries/gait-
analysis
http://www.springerreference.com/docs/html/chapterdbid/70829.html
http://globalseci.com/?page_id=4
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