{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,3]],"date-time":"2025-12-03T09:05:07Z","timestamp":1764752707909,"version":"3.46.0"},"reference-count":48,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,12,2]],"date-time":"2025-12-02T00:00:00Z","timestamp":1764633600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Damage to the osteochondral unit is a common cause of lameness in horses. Published descriptions of MRI findings of osteochondral unit and subchondral damage are currently lacking, and only a few reports describe outcomes in sport horses. The aims of this case series retrospective study were to describe different MRI patterns of osteochondral\/subchondral pathology in the fetlock joint using low-field MRI and to provide outcome information. A total of 35 sport horses were included. Data regarding detailed clinical history, treatment and outcome were evaluated. MRI identified a total of 39 bone lesions: 14 were limited to the subchondral plate, and 25 involved the whole osteochondral unit. In 12 horses, a fissure was observed. Areas of high signal intensity on STIR sequences and low signal intensity on T1-weighted sequences within the trabecular bone were observed in association with subchondral and osteochondral unit damage. At follow-up, a persistent lameness was observed in 11 horses, all of which presented with a lesion involving the whole osteochondral unit. Different MRI patterns consistent with lesions involving either the entire osteochondral unit or only the subchondral bone plate could be identified using low-field MRI. MRI examination should be recommended in horses with inconclusive radiographic findings. Our results suggest that lesions limited to the subchondral bone are associated with a better prognosis.<\/jats:p>","DOI":"10.3390\/ani15233468","type":"journal-article","created":{"date-parts":[[2025,12,3]],"date-time":"2025-12-03T08:44:28Z","timestamp":1764751468000},"page":"3468","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Subchondral and Osteochondral Unit Bone Damage in the Fetlock Region of Sport Horses Using Low-Field MRI: Case Series"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7032-2297","authenticated-orcid":false,"given":"Donatella","family":"De Zani","sequence":"first","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3149-4643","authenticated-orcid":false,"given":"Vanessa","family":"Rabbogliatti","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silvia","family":"Rabba","sequence":"additional","affiliation":[{"name":"Freelance, 28075 Novara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1624-4240","authenticated-orcid":false,"given":"Luigi","family":"Auletta","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6838-8430","authenticated-orcid":false,"given":"Maurizio","family":"Longo","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0444-2784","authenticated-orcid":false,"given":"Davide D.","family":"Zani","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1111\/j.2042-3306.2011.00389.x","article-title":"Low-field standing magnetic resonance imaging findings of the metacarpo\/metatarsophalangeal joint of racing Thoroughbreds with lameness localised to the region: A retrospective study of 131 horses","volume":"44","author":"Powell","year":"2012","journal-title":"Equine Vet. 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