Reliability of Attachment Methods of a Wearable Tibial Monitor

Tibial accelerometers are a common tool used in clinical practice to determine tibial acceleration as well as an athletes return to play ability by utilizing assessments such as the single leg maximal hop test.1-3 In this study, the IMeasureU Blue Trident (IMU, Vicon; Auckland, New Zealand) tibial accelerometer was used to measure peak tibial acceleration (PTA), time to peak acceleration, and rate of acceleration (biomechanical jerk). 16 healthy subjects (10 female, 6 male) volunteered to perform single leg maximal hop tests with two different attachment methods (DST=double sided tape with elastic bandage, SS=manufacturer silicon strap) to determine which is more reliable. It was hypothesized that DST would be more reliable than SS. The device was attached 3 cm proximal to the medial malleolus of the dominant leg and subjects were given two practice trials prior to three real trials with 30 seconds rest between each jump. The subject was given a 3-5-minute rest while attachment methods were changed, and the test was then repeated. Data processing was done with a custom-written MATLAB script which filtered data with a 4th order dual pass Butterworth low-pass filter and statistical analysis was performed in SPSS software. Results showed insignificant differences for peak tibial acceleration, time to peak tibial acceleration, or jerk. Fixation type (DST or SS) did not influence metrics of the IMU device thus clinicians can confidently use either fixation method (DST or SS) to collect data using the IMeasureU Blue Trident device