Inertial measurement unit-based characterization of gait patterns in Asian elephants: clinically sound elephants and elephants with gait abnormalities.

Objective gait assessment is important for detecting locomotor abnormalities in Asian elephants, but clinical interpretation remains constrained by the limited availability of species-specific gait data from clinically sound elephants and the practical constraints of conventional laboratory-based gait analysis. This study aimed to report preliminary observed values for IMU-derived gait parameters in clinically sound Asian elephants and to explore their application for characterizing abnormal gait patterns. Four inertial measurement unit sensors were attached bilaterally over the humerus and femur to record gait data during straight-line walking at a controlled speed. Ten clinically sound elephants were used to describe preliminary observed values, while four elephants with clinically identified abnormal gait patterns were evaluated individually through descriptive case comparison. Temporospatial parameters and duty factor (DF) were analyzed to characterize stance allocation, while cross-correlation coefficients (COF) of left-right vertical displacement waveforms were used to quantify bilateral vertical movement similarity. In clinically sound elephants, stride timing was generally comparable between sides, whereas stance-related parameters showed a consistent side-related pattern. Descriptive comparison with abnormal cases showed case-specific alterations in DF and COF. These findings provide preliminary observed values for IMU-based gait assessment in Asian elephants and support the complementary descriptive use of these parameters for characterizing stance allocation and bilateral vertical movement similarity. Larger clinical datasets are needed to establish clinically relevant thresholds and strengthen their clinical application.