Laminitis involves which hoof structures?

• A. Distal phalanx, laminae, and solar corium
• B. Proximal phalanx, dorsal hoof wall, and frog
• C. Navicular bone and coffin joint
• D. Cannon bone and suspensory apparatus

Answer: (A)

Laminitis mainly targets the laminar attachments that hold the coffin bone (the distal phalanx) to the hoof wall. The key players here are the distal phalanx itself, the laminae (the delicate tissue layers connecting bone to hoof), and the solar corium underneath the sole that can be involved in inflammatory processes. When the laminae become inflamed, the bond between the coffin bone and the hoof wall weakens, causing pain and, in severe cases, rotation or sinking of the coffin bone as the structures lose their supportive integrity. The solar corium can be affected in more advanced cases, contributing to changes in the sole surface and overall hoof health.

Other structures listed don’t form the primary site of laminitis. The proximal phalanx is not the main location of the disease, and while the dorsal hoof wall and frog are part of the hoof’s exterior, the problem in laminitis lies in the laminae between the coffin bone and hoof wall. The navicular bone and coffin joint pertain to different conditions, and the cannon bone and suspensory apparatus are involved in limb support rather than the laminar hoof connection.