Optogait

 

 

OptoGait acquires numerical parameters in real-time
for gait, running and jump tests that can be viewed 
immediately.

 

The easy to read report contains all data, and asymmetries between
the two legs are highlighted instantly. OptoGait does not only detect the
numerical data, but, via small cameras, which can be freely positioned,
it allows the user to acquire images of carried out tests, synchronising
them perfectly with detected events. Without the need for any further
synchronisation between hardware and cameras, the numerous benefits
of cross verification of data and images can be fully used. A more detailed
video analysis can be had by further utilizing the dedicated utility (angle,
distance calculus, graphic tools, etc.).

 

Gait and Run Analysis

Positioned on the side bars of any treadmill (simply leaned on or permanently
fixed with adhesive-tape), OptoGait becomes a portable lab for small
spaces and with reduced costs
. The system is compatible with the wide
majority of treadmills and no synchronization is necessary to start and carry out
a test.

Gait Analysis’ data provided in real time are:

  • Stance phase: The stance phase is the supporting phase of each gait cycle.
    It begins with the contact of the heel and finishes with the set off of the tip of the
    same foot. It is therefore the time between the first and the last contact of two
    consecutive supports of the same foot. It is also presented as a percentage of the
    total gait cycle.
  • Swing Phase: The swing phase begins when the tip of the foot leaves the
    ground and finishes with the contact of the heel. It is therefore the time between
    the last contact of the first support of the foot and the first contact of the following
    support. It is expressed in seconds (sec) and as a percentage of the gait cycle of the
    same foot. The swing time of one foot corresponds to the single support time of the
    other foot
  • Single Support: This is the time between the last contact of the current support
    and the first contact of the following support of the same foot, i.e. the time when only
    one foot touches the ground. The single support corresponds to the swing time of the
    opposite foot. It is expressed in seconds and as a percentage of the total gait cycle time
  • Total Double Support: This is the sum of two partial double supports defined
    DS1 and DS2
  • Step Time: This is the time between the first contact of a foot and the first contact
    of the opposite foot
  • Initial Double Support: This is the first Double Support Time
  • Terminal Double Support: This is the second Double Support Time
  • Step Length: distance between the tip (toe) of two subsequent feet or the distance
    between the heel of two subsequent feet
  • Gait cycle: time between the first contact of two consecutive steps of the same foot
  • Stride Length: distance between the tip of two subsequent footprints of the same
    foot or the distance between the heel of two subsequent footprints of the same foot
  • Speed: Average speed of a single step
  • Acceleration: Speed variations of the two preceding steps
  • Cadence: Rhythm expressed in steps per second
  • Total distance: progressive distance walked/run by a patient
  • Contact Phase: the time between the first contact of the heel and the complete support
    of the foot; the percentage indicates the value with respect to the total contact time
  • Flat Foot: the time the foot completely touches the ground; the percentage indicates the
    value with respect to the total contact time
  • Propulsive phase: the time between the lifting of the heel to the complete set off of the
    tip of the foot; the percentage indicates the value with respect to the total contact time

 

The Gait report is designed specific
for walking or running:

 

The two-dimensional system


Starting from version 1.7 of the OptoGait software it is possible to use a particular
bar configuration for obtaining a two-dimensional measurement area. To the
classic bars (which we will call X), more bars (Y) can be added to form a rectangle,
where new information can be gathered for the gait tests:

  • Step width: distance between the middle support point of each foot
  • Walking Base: distance between the innermost foot support points
    (for superposed steps this value can be negative)
  • Walking Points: middle points between the two support feet; their connection
    defines the gait progress (Line of Progression); conventionally it is expressed in positive
    values if there is a deviation towards left and negative with a rightward deviation
  • Walking Point Gap: progressive variation of the current walking point with
    respect to the previous one

 

 

 

Med Test Typologies

Here you will find some examples of protocols you can perform with different OptoGait configurations:

Many more tests can be performed using the OptoGait system (e.g., zig zag, twist
and turn, obstacles). Not everyone can be symmetrical, and some sports actually
require asymmetry for enhanced performance. The OptoGait systems will measure
left/right differentials. It is up to the doctors, therapists, trainers, etc. to fix, maintain,
or enhance their differentials, deciding if the asymmetry is ideal or needs to be corrected.

This precise measurement of asymmetry allows range of motion/step ability to be
quantified to ensure symmetrical development. By having a client do three consecutive
jumps on each leg, we can determine the rhythm of power via analysis of contact and flight
times. As with gait rhythm, our goal is to maximally reduce the contact and flight time
asymmetries. We may get a false reading of the athlete’s performance/rehabilitation if we
only compare distance achieved for each jump. Accordingly, we must account for the time
to “load and explode” (contact time) or eccentric/concentric. If a client can jump 20 inches
on his/her left leg three times and 20 inches on his/her right leg three times, but the time
of landing and takeoff is different for each leg, an imbalance still exists. We must note this
difference of “load and explode” (contact time) and direct our interventions at restoring
contact time symmetry. This difference in eccentric/concentric ability defines “rhythm of power.”

 

 

Video Feedback

The main idea of this new feature is to show the patient directly some main parameters
of the test he/she is carrying out. This allows to request real-time ‘corrections’ of some
trial anomalies, making the test become an exercise, not only a diagnosis. Particular
attention is paid to the concept of trial anomalies, making the test become an exercise,
not only a diagnosis. Particular attention is paid to the concept of asymmetry, i.e. the
difference between right and left foot (expressed in %) with respect to a particular parameter.

A classic example is a treadmill gait test, where the patient has a monitor in front of him/her
(better if a large-screen TV), where the operator can choose which parameter among those
available to display, depending on the pathology or rehabilitation.

During the gait test, the patient receives a numerical/graphical feedback
(in the form of green/orange/red colors and up/down arrow symbols) indicating what is not
‘working’ and how to correct it (e.g. making the left gait longer or increasing the rhythm, etc.

The new feature (presently available only for Sprint and Gait Tests; Treadmill Gait, Treadmill Run, and Tapping)
is found in Test Module > Execute > Configure, with the two parameters ‘Output second monitor’ and
‘Save Test Data.’

When the ‘Output Second Monitor‘ option is selected, a window is created on the second
monitor (or on the same monitor, when the second one is not physically present), where the
displaying of one test parameter asymmetry can be configured (e.g. the step length for a gait test)
both as a numerical value and as a graphical bar display.  

Instead the ‘Save Test Data‘ parameter is used (if set on No) when, as previously described,
the patient must ‘exercise’ and it is not necessary to save the test at the end of the trial. In this
case no data ‘sampling’ and, most of all, no webcam video sampling is carried out, thus reducing
the used disk space (temporary video files and memory swap files) as well as CPU use.

The parameter to be displayed is configured in the second window on a side panel bar, which can
be minimized (<< key).

The parameters, which can be set, are the following:

  • Type: the parameter to be displayed (changes depending on the test type carried out;
    e.g. for a tapping test, the flight and contact times, rhythm, etc., for run tests, speed, acceleration,
    etc., whereas for gait tests, regular gait analysis parameters, such as stance, swing, single support,
    step length, etc.).
  • Data Window: the amount of data used for calculating the asymmetry (the last N are used);
    the higher the data, the better the ‘average’ and the more real the value, but it will be more difficult
    for the patient to try and correct his/her asymmetry.
  • Warning Threshold: if the asymmetry is lower than this percentage, the value is displayed on
    a green background, and if it is higher, the background color is orange
  • Bad Threshold: if the asymmetry is lower than this percentage, the value is displayed on an
    orange background, and if it is higher, the background color is red. Setting for example the warning
    threshold at 5% and the bad threshold at 10% the following background colors will be used:

0 <= value< 5  -> green

5 <= value<10  ->  orange

>= 10 -> red

  • Trend: if the asymmetry value exceeds the warning threshold, an indication for the
    patient is displayed with an arrow on the value bar. The indication can be to increase the
    lower value or to decrease the higher value.

 

Bio Feedback

The BioFeedback module (available as of version 1.10) was inspired by the “Video Feedback
feature where the user can see some basic test parameters in real time on a second monitor
(usually a large TV or a screen/tablet placed in front of the treadmill).

By trying to optimize these parameters while performing the test, for example by minimising
asymmetries or lengthening the stride, the patient “trains” and uses the system as a working
tool instead of as an instrument of diagnosis
.

The main difference compared to the normal tests described in the previous sections is that
data are NOT saved in the BioFeedback module and are NOT paired with any user; it is just
a very fast “start & run” module with a minimal user interface, designed also to be used directly by
the end patient instead of by the technician/operator.

BioFeedack module is available for treadmill walk/run tests and march in place.

A handy interface, with panels that can be hidden, lets the operator or the patient set the “bad”
and “warning” thresholds and some parameters as reference values, starting foot, treadmill speed
and rhythm of the metronome.

 

 

Optogait website