Coffin Joint
The coffin joint lies between the second and third phalanges of each limb. The joint space is located under the interface of the hoof and haired skin on the limb (coronet band). Horses with coffin joint pain present with a wide range of symptoms: from acute lameness to poor athletic performance. The forelimbs are more commonly affected. Physical examination findings include coffin joint distension and pain on joint flexion. The most common causes of lameness in the coffin joint are synovitis (inflammation of the joint capsule) and osteoarthritis. Other abnormalities include: trauma, ligament inflammation (desmitis), and fractures to the phalanx bones.