Which joints are primarily involved in the forelimb stay mechanism?

Which joints are primarily involved in the forelimb stay mechanism?

• A. Elbow and shoulder joints
• B. Pastern and coffin joints
• C. Carpal joints and the metacarpophalangeal (fetlock) joint
• D. Stifle and hock joints

Answer: (C)

The stay mechanism in the forelimb relies on a locking system that is centered in the carpal region and the fetlock. When the limb bears weight, ligaments and tendinous structures around the carpus and the metacarpophalangeal joint (fetlock) tighten in a way that “locks” the limb, letting the animal stand with little muscular effort. The deep digital flexor tendon helps maintain extension at the fetlock, while the suspensory and related ligaments prevent overextension, keeping the limb upright. Elbow and shoulder are more proximal joints and aren’t the primary sites for this locking action. The pastern and coffin joints are distal to the fetlock and are not the main contributors to the forelimb stay mechanism.

The stay mechanism in the forelimb relies on a locking system that is centered in the carpal region and the fetlock. When the limb bears weight, ligaments and tendinous structures around the carpus and the metacarpophalangeal joint (fetlock) tighten in a way that “locks” the limb, letting the animal stand with little muscular effort. The deep digital flexor tendon helps maintain extension at the fetlock, while the suspensory and related ligaments prevent overextension, keeping the limb upright.

Elbow and shoulder are more proximal joints and aren’t the primary sites for this locking action. The pastern and coffin joints are distal to the fetlock and are not the main contributors to the forelimb stay mechanism.