Which flexural deformity is this yearling exhibiting?

Which flexural deformity is this yearling exhibiting?

• A. Carpal flexural deformity
• B. Metacarpophalangeal joint flexural deformity
• C. Proximal interphalangeal joint flexural deformity
• D. Fetlock hyperextension

Answer: (B)

Flexural deformities in young horses arise when tight flexor tendons and ligaments limit joint extension. When this happens at the fetlock, the metacarpophalangeal joint, the fetlock remains abnormally flexed and the limb carries a shortened, stiff appearance at the level of the ankle region. This is the most common flexural issue seen in yearlings, because the tendons around the fetlock are particularly susceptible to contraction during rapid growth. If the problem involved the pastern joint (proximal interphalangeal joint), you’d see a different angle at the lower leg where the pastern itself is contracted and sits in a more flexed position relative to the cannon bone and coffin joint. Involvement of the carpus would present as stiffness or contracted posture at the knee area rather than at the fetlock. Fetlock hyperextension, on the other hand, would present as an over-extended fetlock rather than a flexed one. So the described scenario fits a flexural deformity at the fetlock, identifying it as metacarpophalangeal joint flexural deformity.

Flexural deformities in young horses arise when tight flexor tendons and ligaments limit joint extension. When this happens at the fetlock, the metacarpophalangeal joint, the fetlock remains abnormally flexed and the limb carries a shortened, stiff appearance at the level of the ankle region. This is the most common flexural issue seen in yearlings, because the tendons around the fetlock are particularly susceptible to contraction during rapid growth.

If the problem involved the pastern joint (proximal interphalangeal joint), you’d see a different angle at the lower leg where the pastern itself is contracted and sits in a more flexed position relative to the cannon bone and coffin joint. Involvement of the carpus would present as stiffness or contracted posture at the knee area rather than at the fetlock. Fetlock hyperextension, on the other hand, would present as an over-extended fetlock rather than a flexed one.

So the described scenario fits a flexural deformity at the fetlock, identifying it as metacarpophalangeal joint flexural deformity.