The pathogenesis and treatment of osteomyelitis and laminitis in a stallion after the prolonged topical application of formalin to the distal phalanx.

This research discusses the case of a horse suffering from bone infection and foot inflammation, attributed to the prolonged application of formalin, a disinfectant. The horse was treated via surgery and special shoeing, illustrating recent developments in managing these conditions.

Case Background and Symptoms

• The study focuses on a 12-year-old Quarterhorse stallion experiencing severe lameness in its left front foot. The horse also had a 3 cm cavity in its sole, penetrating to the solar surface of the horse’s distal phalanx (the terminal bone of the foot).
• Radiographic examinations revealed osteomyelitis, an infectious inflammation of the bone, and a sequestrum, a piece of dead bone separated from healthy bone, most likely induced by the extended topical application of a 10 percent formalin solution.

Treatment Procedures and Results

• The horse underwent surgical treatment to remove the sequestrum and clean out the infected bone tissue, a procedure called curettage.
• After the surgery, the horse was fitted with heart bar shoes on both front feet. These types of shoes are specifically designed to support the frog (a soft, cushion-like structure in the horse’s hoof), redistribute weight, and alleviate discomfort.
• However, radiographic exams conducted eight months post-surgery showed a significant rotation of the distal phalanx despite consistent shoeing with the therapeutic shoes.

Additional Intervention Measures and Outcome

• Faced with the ongoing issue, the researchers performed an additional surgical procedure. It involved the resection of the dorsal wall of the hoof at the toe to remove the pressure caused by the laminar wedge, a displacement that occurs in advanced stages of laminitis, a painful condition affecting the horse’s feet.
• Combined with the stabilising function of the heart bar shoe, this surgical intervention allowed to realign the distal phalanx closer to the natural skeletal axis by approximately 30 degrees, 26 days post-operatively.

Conclusion

• This case demonstrates some of the latest advancements in treating laminitis, stressing that effective treatment can be achieved given that the value of the animal justifies the required time and investment.