A clinical perspective on lameness originating in the carpus

Area of Science:

• Equine orthopedics
• Biomechanics of equine joints
• Veterinary sports medicine

Background:

• The equine carpus is crucial for dissipating loading stress, preventing injury through anatomical and physiological adaptations.
• Joint surfaces transfer axial forces to interosseous ligaments, a primary mechanism for avoiding carpal injury.
• Specific regions, including the medial intercarpal and dorsal radial carpal joints, are susceptible to maximal chronic and acute stress.

Purpose of the Study:

• To investigate the mechanisms of carpal injury in training horses.
• To identify the limitations of the equine carpus in neutralizing excessive loading stress.
• To understand the bone remodeling processes leading to carpal fractures.

Main Methods:

• Analysis of clinical experience and understanding of carpal pathophysiology.
• Evaluation of the anatomical and physiological capacity of the equine carpus.
• Examination of stress-induced bone changes and loss of structural integrity.

Main Results:

• The equine carpus effectively neutralizes most loading stress.
• The medial intercarpal and dorsal radial carpal joints cannot neutralize maximal chronic or acute supraphysiological loads.
• Progressive osseous remodeling and stress lead to fractures in horses under training.

Conclusions:

• Vulnerability in specific carpal joint areas can lead to injury despite the carpus's overall protective capacity.
• Overwhelming stress exceeding bone's adaptive capacity results in loss of structural integrity and fracture.
• Understanding these mechanisms is vital for preventing carpal fractures in athletic horses.