Diagnostic Tests
Video and The Force Line. Video allows clinicians to review and study a person’s gait pattern in slow motion. Two cameras provide a simultaneous side
and a front view of the individual. One major innovation created at MossRehab is the force line visualization technique. It
involves superimposing a laser representation of the force on a video of the individual in real time. By doing so, clinicians
can see the force’s line of action as the person walks.
As an example, cinicians use the force line to make adjustments to a prosthesis for better performance.
Force Plates. The lab has acquired an additional two force plates and so at present has four plates that provide over 30 square feet of
force sensitive floor. When a patient walks over this region, we can measure the total 3-dimensional force under each foot.
Electromyography (EMG): Allows clinicians to evaluate relative levels of activity from muscles while patients perform various activities, such as
walking or stair climbing. Clinicians can record up to 52 channels of surface muscles and/or deeper muscles by using fine
wire electrodes.
Coda MPX30 & CX1 Motion Analysis Systems. A Coda MPX30 motion analysis system enhances the lab's 3-D motion capture and analysis capabilities. The system allows for
simultaneous, bilateral, three-dimensional capture of motion using infrared lights and special sensors. It is an active marker
system, which means its sensors are unique and will never get mixed up with nearby sensors. In addition, the system does not
use encumbering wires—allowing patients to walk naturally while we record their movements. It also allows almost instantaneous
data processing, allowing us to explain the evaluation process to our patients as they watch animated images of themselves
walking.
The lab has acquired an additional mobile motion capture camera. This unit literally allows for ‘gait analysis on the run’.
By connecting the unit to a laptop, motion capture could be done outside or at a remote location.
A subject is shown instrumented for motion analysis. The various wands and straps have miniature infrared lights attached
to them that are tracked by sensors as the subject walks. Note, the cable shown is due to simultaneous EMG collection.
Our system generates animations like the sample shown here. It shows a stick figure of a patient walking along with virtual
ground reaction force (lower left), joint angles, moments and powers. Note the blue bar is time synchronization between all
images.
Gaitmat. This is a set of 10,000 miniature pressure switches mounted in the floor. As the individual walks over this area of the floor,
clinicians record a map of the footfall pattern. In addition, clinicians can record and calculate left/right stance, swing,
and double support times, step and stride length, step and stride times and base of support, along with reference values from
speed, age and gender normalized data.
Sample Gaitmat report shows graphic and numerical data on walking speed, symmetry and step length.
TekScan Fscan. This system provides discrete, quantitative, dynamic pressure readings from a thin sensor placed inside the shoe. This technology
is especially valuable for those with insensate feet (diabetics, spina bifida) to prevent foot ulcers and infection and for
patients with foot pain. With this system, clinicians can recommend foot orthotics or shoe modifications designed to re-distribute
foot pressures with this system.
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A two dimensional display of the pressure distribution under the foot as an individual stands quietly. Dark areas correspond
to relatively higher pressure regions.
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A three dimensional representation of pressure distribution under the same foot as shown above. Here, the additional spatial
information assists in visualization of the pressure gradient.
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This animation shows how the pressure under specific areas of the foot change as a step is taken during walking. Such a measurement
can be used to identify regions of abnormally high pressure that may lead to increased pain, sores or ulcers and deformities
over time.
Metabolic Cart and Heart Rate Monitor: Both these tools are used to estimate the energy expended while a patient performs a particular activity, such as walking.
