Reliability Of IMU Derived Kinematic Measures During The Forward Lunge: 3399 Board #220 May 29 2:30 PM - 4:00 PM

The integration of inertial sensor data into the clinical environment and beyond, demonstrates the potential of improved clinical interpretation of an individual’s functional movement capacity. Previously this has only been possible through the use of expensive laboratory-based motion capture systems. The forward lunge, a lower limb functional movement which exaggerates the gait cycle is commonly used by clinicians to assess lower limb strength, flexibility and balance. Combining Inertial measurement units with the forward lunge exercise could provide a quantified measure which was previously not possible in the clinical setting. PURPOSE: To determine the intrasession-reliability of kinetic measures derived from shank based inertial sensors during a forward lunge. METHODS: Twenty-three healthy participants took part in the study (12 Male, 11 Female, 30.8 ± 8.6yrs, 1.7 ±0.9m, 65.3 ± 10.8kg). Each participant performed 3 sets of 5 lunges bilaterally, each with a 10 min rest period adequate to establish intra-session reliability. Lunge distance and stance was set as 100% of leg length and hip width respectively (± 5%). IMUs were worn on the lateral aspect of each shank. The lunge was segmented into initiation, initial contact, mid-point, and termination. Peak & root mean squared (RMS) of total acceleration signals of the shank based IMU were taken for all lunges. Intraclass correlation coefficients (ICCs) were calculated based on a mean rating (k=3), absolute agreement two-way mixed effects model. Intra-session reliability was defined as poor (ICC<0.5), moderate (0.5-0.75), good (0.75-0.9) or excellent (>0.9). RESULTS: ICC values ranged from 0.916 to 0.981 for left limb peak acceleration and 0.903 to 0.978 for right limb peak acceleration. ICCs for RMS of left and right limb ranged from 0.908 to 0.979 and 0.899 to 0.977 respectively. CONCLUSIONS: The IMUs showed good to excellent reliability for both peak and RMS total acceleration across both limbs during the forward lunge. This demonstrated the potential for their integration as a clinical tool to provide quantified measures of an individual’s forward lunge performance.