The Biometrics Flexible electrogoniometer has the potential to allow physiotherapists to record the motion of joints during dynamic functional activities. In order to make full and appropriate use of this device it is necessary to comprehend the design, attachment and measurement properties of this instrument. The results of these studies indicate that the electrogoniometers are stable, precise, accurate and repeatable in performance. Little variation exists between electrogoniometers or between the performance of an electrogoniometer at different times, on different days or in different environmental conditions. Small hysteretic effects and inaccuracies are present in the devices but these are of the order of 1 or 2 degrees. The system is not affected by environmental pollutants such as heat, electrical interference, convection currents or noise and therefore can be used in a variety of hospital settings. The device is however affected by abduction/adduction angle with angles of 40° or more giving substantial errors when associated with simultaneous flexion or extension. The electrogoniometer should be attached firmly and securely across the joint in an essentially planar configuration. Provided care is taken to handle and mount the electrogoniometers appropriately they appear to record knee movement faithfully and accurately and the system is capable of giving valid and meaningful clinical data.
- assistive technology