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

Overview

• This study investigated stress-related bone injuries in the carpal joints of show jumping horses and assessed their impact on lameness and subsequent performance over one year.
• Findings indicate that although these injuries cause mild lameness, they rarely prevent horses from returning to and maintaining competitive performance.

Study Objective

• To describe the types and locations of carpal joint lesions causing forelimb lameness in show jumping horses.
• To evaluate the one-year post-diagnosis performance outcomes of affected horses.

Study Population and Methods

• 15 show jumping horses were retrospectively selected from a larger pool of 5,515 evaluated between 2013 and 2023 at a referral center.
• The median age was 9 years, primarily Selle Français breed, with some other breeds included.
• Inclusion criteria included:
  • Forelimb lameness localized to the carpal (wrist) region.
  • Confirmed diagnosis through perineural or intra-articular analgesia and/or increased radiopharmaceutical uptake on bone scintigraphy.
• Exclusion criteria:
  • Abnormal limb conformation.
  • History of trauma.
  • Extra-articular soft tissue injuries.

Clinical Presentation

• Owners typically reported chronic lameness and decreased performance.
• Physical examination often revealed mild to moderate thickening on the dorsal aspect of the carpus in more than half the horses.
• Lameness was generally low-grade (grade 1 to 2 out of 5).
  • Lameness was more noticeable when the affected limb was on the outside of the circle during lunging exercises.
  • A visible reduction in the cranial (forward) phase of the stride was observed.

Lesion Types and Distribution

• Carpal joint lesions were primarily found in the middle carpal joint in 12 of the 15 horses.
• The third carpal bone was the most commonly affected bone (12 of 15 cases).
• Lesions included:
  • Sclerosis (hardening/thickening of bone).
  • Osteolysis (bone loss/destruction).

Performance Outcomes

• One year after diagnosis:
  • 12 out of 15 horses returned to competition.
  • All horses competing at higher levels (jumps >140 cm) resumed competition at their previous height (7 of 7).
  • 10 of the 15 horses maintained or improved their prediagnosis performance level.

Conclusions and Implications

• Stress-related bone injuries in the carpal bones should be considered as a cause of subtle, low-grade lameness and reduced performance in show jumping horses.
• Despite causing clinical signs, these stress injuries rarely limit long-term return-to-sport outcomes for most horses.
• Veterinarians should actively investigate such lesions when chronic forelimb lameness affects performance, as prognosis for competition remains generally favorable.