Total removal of the fourth metacarpal bone in an Icelandic horse.

Fractures of the splint bones are the most common fractures in horses. Various treatment options for splint bone fractures (MC/MT II and IV), including conservative and surgical management, have been described. This report describes an acute splint bone fracture due to external trauma in a 17-year-old Icelandic mare. The fracture was diagnosed as an open multifragment fracture of the proximal third of the fourth metacarpal bone (MCIV) in the right front limb. Surgery was performed with the horse under general anaesthesia. The distal fragments were removed, and the distal part of the proximal remnant splint bone was cut with an osteotome. During the postoperative period, a routine x-ray-control two days after surgery showed a dislocated fracture of the remaining proximal part of the fourth metacarpal bone. In a second surgery, the proximal part of MCIV was entirely removed. After a reconvalescence period of 5 month, the horse reached her previous level of performance as a leisure horse. The mare is still free of lameness 6 years after the incident.