Equine sport modalities influence the prevalence and predisposition of musculoskeletal injuries in horses. This study aimed to evaluate the prevalence of location and type of orthopedic injuries of horses undergoing various physical activities. Data from 116 horses of different breeds and ages was analyzed. Physical activities included dressage, racing, polo pony, jumping, work and western performance. All horses had history of orthopedic lameness diagnosed by radiographs and/or ultrasound scans. The effect of sport on the affected anatomical site and type of lesion was performed using Fisher's exact test. Desmitis was more prevalent in animals that performed western sports than in the working ones. The number of fractures was greater in racing and polo pony animals than in working horses. Stifle lesions were more prevalent in dressage horses than working horses and had lower occurrence of shoulder injuries than jumping horses. Hind limb tendon injuries were lower in jumping than in dressage and western horses. We conclude that there is a relationship between location and type of injury and physical activities. In racing horses there is a predominance of young animals and higher prevalence of orthopedic injuries from traumatic events such as tendonitis, desmitis and fractures. In physical activities that require longer training and that animals were used for longer periods, eg. jumping, polo pony, dressage and work, age-related degenerative, such as joint disease, were predominant. In western sport animals the most common lesion was desmitis. Regarding limbs, forelimb injures were more often observed in racing horses, polo pony, jumping and working animals; whereas, dressage and Western sports horses presented more injuries in hind limbs.

In modern society the work and athletic performance of horses has led to a very important animal production sector in which Brazil possesses the third largest horse stock. Among all equine lesions described, metacarpophalangeal (fetlock) joint lesions are considered one of the main causes of lameness. Consequently, there is a need to improve the understanding and diagnosis of these injuries. The most efficient imaging diagnostic methods for the fetlock region are computed tomography, radiography and ultrasound. Imaging studies of the anatomical structures involving this joint are extremely important to obtain a more precise diagnose. The present study was performed in order to evaluate the capacity of different imaging diagnostic modalities to detect a variety of lesions in different fetlock structures. Twenty horses (Equus caballus) used for horsemanship activities were referred to the Department of Animal Reproduction and Veterinary Radiology of São Paulo State University, Botucatu campus, with clinical signs of metacarpophalangeal joint injuries. Horses were submitted to radiographic and ultrasonographic exam and computed tomography scan. Image analysis revealed a significant capacity of these methods to characterize lesions in this region. However, computed tomography provided broader and better evaluation of lesions in bones and adjacent structures, because it allows the analysis to be performed on three-dimensional projections, with attenuation coefficients (window selections) and tissue density measurement through Hounsfield Units (HU).Keywords: computed tomography, radiography, ultrasonography, metacarpophalangeal joint, horses RESUMO As atividades desempenhadas pelo cavalo na sociedade contemporânea são diversas, e o Brasil é portador do terceiro maior plantel mundial de equinos. Entre as várias afecções descritas em cavalos atletas, as lesões na articulação metacarpofalangeana (boleto) são consideradas as principais causas de claudicação. Por isso

Estudo da correlação da densitometria óssea e do perímetro diafisário medial do terceiro metacarpiano em equinos[Correlation study on equine bone densitometry and third metacarpus diaphyseal perimeter]