Evaluation of cartilage injury in horses with osteochondral fragments in the metacarpo−/metatarsophalangeal joint: A study on 823 arthroscopies

Abstract

BackgroundOsteochondral fragment removal is commonly performed but there are little scientific data supporting this procedure in the absence of clinical signs. More information is needed to facilitate clinical decision‐making regarding fragment removal of the metacarpo−/metatarsophalangeal joint.ObjectivesTo assess prevalence of cartilage injury in the equine metacarpo−/metatarsophalangeal joint and its association to fragment size, location, age and lameness.Study designRetrospective observational study.MethodsClinical records, including radiographs of 823 metacarpo−/metatarsophalangeal joints (640 horses) that underwent arthroscopic fragment removal, were reviewed. Fragment size, intra‐articular fragment location and cartilage injury score were recorded. Presence of synovitis was retrospectively evaluated in 157 joints. Kruskal–Wallis and Mann–Whitney tests were used for group comparisons, and Dunn's post hoc test was applied for multiple comparisons. Linear regression analysis was used to assess strength of association between age and mean cartilage score. Univariable regression analysis was performed and variables with p < 0.2 were used in the final mixed‐effects multivariable model to which backwards stepwise selection was applied. Significance level was p < 0.05.ResultsCartilage injury was present in 28.8% (95% CI = 25.8–32.0) of joints. Lameness was not associated with fragment location or fragment size. Fragment size was not associated with cartilage injury. Age (OR = 1.35, 95% CI = 1.22–1.48, p < 0.001) and lameness (OR = 5.03, 95% CI = 2.27–11.68, p < 0.001) were associated with cartilage injury as well as fragment location (palmar/plantar, OR = 0.22, 95% CI = 0.13–0.38, p < 0.001), with dorsal fragments being more likely to be associated with cartilage lesions than palmar/plantar fragments. There was a significant association between age and mean cartilage score (b = 0.18, 95% CI = 0.14–0.22, p < 0.001).Main limitationsThe series included a heterogenous group of horses of different breed, sex, age and use. Data were collected retrospectively and could, in parts, not be fully evaluated.ConclusionsEarly fragment removal, especially in joints with dorsal fragmentation, can be beneficial to avoid future cartilage injuries in equine athletes.

Clinical insights: Outcomes of juvenile orthopaedic lesions

“…16 This observation supports the study performed by Goldkuhl in 2023, where Warmbloods older than 7 years were more likely to have articular cartilage damage than juveniles with metacarpophalangeal joint osteochondral fragments. 17 Furthermore, this study identified lesions on the sagittal ridge and dorsal proximal P1 were significantly more likely to have cartilage lesions compared with palmar/plantar P1 fragments. Their conclusions were similar and related to the stabilised embedded nature of the osteochondral fragments in the palmar/plantar pouch.…”

“…16 Another study analysed subsequent cartilage injury apparent in mainly Warmbloods with metacarpophalangeal joint osteochondral fragments. 17 These papers expand the field of interest and move the focus away from solely Thoroughbreds. In contrast to other OCD fragments where synovial inflammation has been reported, palmar/plantar osteochondral fragments seem not to, and indicated surgery in unproven juveniles can be delayed.…”

“…Lastly, over 70% of horses that were lame had cartilage damage, and as articular cartilage has minimal capacity to heal and repair, pre-emptive removal of dorsal osteochondral fragmentation can be seen as beneficial. 17 The articles summarised above highlight an improvement in the understanding of outcomes for orthopaedic conditions that foals and yearlings are afflicted with, as well as our improvement in treatment.…”