Introduction to the
study of human walking
·
Approaches
to the study of gait
·
Tentative schedule of lectures and laboratory experiences
for Spring 2002
·
Laboratory
activities:
Basics
of gait terminology
We define parts (or "phases") of the gait cycle using
conventions popularized by the Pathokinesiology
Laboratory at Rancho Los Amigos Hospital (RLAH) in Downey,CA.
One complete gait cycle is measured in
percentages:
·
where one limb's initial contact with the ground is designated as
0 percent
·
and
that limb's next initial contact is designated as 100 percent.
·
If
a person's pattern is symmetrical, initial contact of the opposite limb occurs
at 50 percent.
RLAH (or
"Rancho") terminology divides the gait cycle into stance and swing
phases:
·
Stance phase accounts for 60 percent of gait
cycle, and includes:
1.
loading response
2.
midstance
3.
terminal stance
4.
preswing
·
Swing phase accounts for 40 percent of gait
cycle, and includes:
1.
initial swing
2.
midswing
3.
terminal swing
Each gait cycle includes
·
two
periods of single limb support
·
two
periods of double limb support (each accounting for about 10% of the cycle)
1.
loading response from 0 to 10 percent
2.
preswing from 50 to 60 percent
By definition, when one limb is in loading
response, the other limb is in preswing.
Functional
features of a locomotion pattern
1.
Stability
·
Against
gravitational forces
·
Against
inertial forces
2.
Propulsion
(Adding energy to system)
3.
Efficiency
(Minimizing energy expenditure)
·
minimizing changes in kinetic energy
·
"shock absorption"
·
prevention of "repetitive injury"
·
minimizing changes in potential energy
