Prevalence of subchondral bone pathological changes in the distal metacarpi/metatarsi of racing Thoroughbred horses

Abstract

Objectives: To investigate the prevalence of microscopic subchondral bone injury in the distal metacarpi/tarsi of Thoroughbred racehorses and associations with recent and cumulative training history. Methods: Metacarpi/metatarsi were obtained from postmortem examination of Thoroughbred racehorses. The severity of palmar/plantar osteochondral disease (POD) was graded in forelimbs from 38 horses and in hindlimbs from a separate cohort of 45 horses. Forelimb samples were embedded in methyl methacrylate and examined using backscattered scanning electron microscopy. Microfracture density in the condylar subchondral bone was determined. Horizontal subchondral bone fractures were identified in hind..