Stress-related bone injuries of the carpal joints in show jumping horses rarely limit long-term performance: a retrospective study of 15 cases.

Abstract: To describe the type and distribution of carpal joint lesions causing lameness in show jumping horses and describe their 1-year performance outcomes. Unassigned: 15 show jumping horses (median age, 9 years; IQR, 8 to 11 years) of 3 different breeds, mostly Selle Français, evaluated at a referral center between 2013 and 2023. The inclusion criterion was forelimb lameness localized to the carpus, confirmed by perineural or IA analgesia and/or increased radiopharmaceutical uptake on scintigraphy. Horses with limb conformation abnormalities, a history of trauma, or extra-articular soft tissue lesions were excluded. Unassigned: Owner complaints included chronic lameness and poor performance. Mild to moderate dorsal carpal thickening was observed in more than half of the cases. Lameness was typically low grade (American Association of Equine Practitioners grades 1 to 2) and more pronounced when the affected limb was on the outside of the circle during lunging, with a visible reduction in the cranial phase of the stride. Unassigned: Of the 5,515 show jumping horses evaluated during the study period, 15 met the inclusion criteria. Middle carpal joint lesions were found in 12 of 15, most often affecting the third carpal bone (12 of 15) with sclerosis and/or osteolysis. At 1 year, 12 of 15 horses had returned to competition, including all horses competing at heights > 140 cm (7 of 7); 10 of 15 maintained their prediagnosis performance level. Unassigned: Stress-related bone injuries of the carpus should be considered as a potential source of low-grade lameness and suboptimal performance in show jumping horses. Carpal bone stress lesions may not limit long-term competition outcomes in most cases.