Inertial measurement unit (IMU) systems for horses provide objective lameness detection that can identify welfare-compromising gait asymmetry before it becomes clinically obvious.
IMU-based lameness detection welfare value lies in its ability to identify subtle gait asymmetry before horses are showing obvious pain signals. Horses stoically continue working despite early lameness, and subtle gait asymmetry that human observers miss can represent ongoing welfare compromise - particularly when repeated impact on an affected limb delays healing or worsens underlying pathology. Technology that detects this early enables intervention that prevents welfare compromise from becoming established pain and tissue damage. The welfare case for routine IMU monitoring is strong for horses in regular work.