Effects of a Heated Vibration Massage Pad on Horses: Randomized, Blinded Measures of Mechanical Nociception, Behavior, and Spinal and Limb Kinematics

Therapy devices are widely marketed to horse owners, claiming to improve well-being, support musculoskeletal function, and aid injury rehabilitation, though many claims lack scientific evidence. This study evaluated the immediate (part A) and four-week (part B) effects of a heated vibration massage pad applied to the thoracic epaxial region on mechanical nociceptive threshold (MNT), behavior, and kinematics of horses. A randomized, blinded design was employed with a convenience sample of 10 riding horses in treatment and control groups. Inertial motion sensors and limb markers captured kinematic data, behavior was analyzed using EquiFACS, and MNT was measured using pressure algometry. Immediately (part A) following application of the heated vibration massage pad, there were no significant changes in MNT, behavior, or dorsoventral range of motion at the poll, wither, pelvis, or tuber coxae during walk or trot, nor in minimum difference, maximum difference, and range of motion at the poll, wither, and pelvis in trot, in the treatment or the control group (all P > 0.05). Similarly, stride length and duration in walk remained unchanged. However, in trot, the treatment group exhibited minor reductions in stride length (P = 0.025, d = 0.2) and hindlimb retraction (P = 0.005, d = 0.5), with increased stride duration (P = 0.044, d = −0.17). After four weeks of regular use (part B), the treatment group showed significant increases in stride length during trot (309.8 cm ± 37.8 vs. 334.4 cm ± 35.1, P = 0.017, d = 1.38) as well as increased forelimb retraction, hindlimb protraction, and retraction. While immediate effects were negligible, consistent use of the heated vibration massage pad may enhance limb kinematics, suggesting its potential as a convenient addition to maintenance regimes for riding horses.