Efficacy of an Oral Chondroprotective Joint Supplement on Stride Length and Gait Symmetry in Aged Geldings with Chronic Lameness

Oral joint supplements (OJSs), specifically those containing glucosamine and chondroitin sulfate, are some of the most popular feed additives fed by horse owners. However, evidence of the efficacy of these nutraceuticals in vivo is lacking. To investigate the impacts of an OJS on equine lameness, 40 geldings (18 ± 7 yr) with chronic lameness and AAEP lameness grades between 2 and 4 (as scored by a veterinary sports medicine and rehabilitation specialist) were enrolled in the study. Horses were stratified by lameness grade, BCS, and weight, and then randomly assigned to receive a placebo powder or an OJS daily for 6 wks. Stride length measurements and lameness evaluations were performed every 2 wk. There was no effect of treatment or treatment-by-day interaction for stride length, though day affected both walk (p = 0.04) and trot (p < 0.01). Only day affected lameness grade, with the lowest average score on d28 (p = 0.04). There was no evidence of supplementation improving gait symmetry over time. As such, there is no evidence to support efficacy of the tested OJS when fed for 6 wk. These results emphasize the importance of well-controlled studies and support continued development of evidence-based management strategies for equine joint health.