Coffin bone fracture in a horse.
The radiographic images below are from a horse that presented for a 2 week history of non-weight bearing lameness in a forelimb. The horse had been treated for a suspect abscess with minimal clinical improvement. Interestingly, the horse was minimally responsive to hoof tester exam.
In the lateral radiograph (Figure 1) there is no obvious explanation for the lameness. However in the subsequent radiographs (Figures 2-4) the cause for the lameness is evident. A large fracture of the coffin bone is apparent. The fracture extends from the toe region all the way through the joint!
In Figures 3 and 4, the fracture line appears to encompass the entire length of the coffin bone. The prognosis for future soundness depends on whether the fracture communicates with the coffin joint. If it does, the prognosis for soundness is poor due to the likelihood of developing of advanced osteoarthritis. This type of fracture will eventually heal with the correct shoeing and adequate rest. However, the prognosis for return to soundness is guarded due to the severity of this fracture!