Objective lameness assessment of 235 horses undergoing lameness examination in Brazil: A retrospective study

Lameness, which arises from functional or structural changes in the limbs or axial skeleton, causes asymmetry in the movement of the equine head and/or pelvis. This study aimed to investigate the lameness patterns of horses that underwent lameness examination or monitoring during the years 2016 to 2020. This retrospective study used data from the lameness examination, evaluated using an objective assessment with body-mounted wireless inertial sensors. The lameness examination comprised clinical history, static inspection, palpation, gait evaluation (for which the animals were equipped with a wireless inertial sensor system), flexion tests, lunging examination, diagnostic anesthetic blocks, and imaging examinations. Based on objective assessment data, the condition of lameness, limb with primary lameness, type of lameness, intensity, and location of lameness were determined. Of the 235 animals included in this study, 93,6% presented lameness. Of the animals with lameness, 59,5% had forelimb lameness and 40,5% had hindlimb lameness. The most frequent lameness condition was primary lameness in one limb and secondary lameness in the other. Impact lameness was the most frequent type in both the forelimb and hindlimb. Moderate-to-severe lameness was the most frequent level of intensity. Regarding the lameness location, in the forelimb, the distal region was the most affected, while in the hindlimb, the proximal lower region was the most affected. We conclude that forelimb lameness is more frequent in horses examined in southern Brazil and mainly affects the distal limb region.