RHYTHMIC WEIGHT SHIFT (RWS)
Description
RWS Report
Functional Implications
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Description
The RWS test quantifies the patient's ability to rhythmically move their Center of Gravity (COG) from left to right (lateral) and forward to backward (anterior/posterior) between two targets at three distinct speeds: slow (3 second peak to peak pacing), medium (2 second pacing), and fast (1 second pacing). The measured parameters are the on-axis (intentional) COG movement velocity and the directional control.
For each of the three paces, the subject is instructed to rhythmically move the COG cursor from side to side or front to back between two targets.
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RWS Comprehensive Report
- The COG traces for each trial are shown at the top of the report.
- On-Axis Velocity is the average speed in degrees per second of the rhythmic movement along the specified direction. The ideal velocity is shown by the horizontal line on the graph.
- Directional Control is a comparison the amount of movement in the intended direction (toward the end line) to the amount of extraneous movement (away from the end line).
- The shaded area on each graphic represents performance outside of the normative data range. Green bars indicate performance within the normal range; red bars indicate performance outside the normal range. A numerical value is given at the top of each bar.
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Functional Implications
Normal subjects attain the required average velocities by maintaining the rhythm set by the pacing target and by covering the full distance between the specified movement boundaries. At the same time, their movements are straight and well coordinated, with motions in the off-axis direction being a small percentage of the on-axis motion. Patients with motor disorders disrupting normal rhythmic movement control may exhibit slower than normal movement velocities, poor directional control, or a combination of these two problems.
Functional consequences include an inability to meet the timing demands of the environment, such as crossing the street, stepping onto elevators/escalators, etc. Instability may result when performing activities that require rapid movement speeds, variability in speeds, or changing directions. Rhythmic, reciprocal movement patterns are required in many high-level athletic and leisure interests.
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