Multifactorial severe lameness in a horse originating from the fetlock region as a diagnostic challenge – a case report

A 6-year-old thoroughbred gelding was admitted to the clinic with acute severe lameness and swelling of the front limb fetlock area. The traditional examination methods (clinical, radiography, and ultrasonography) were insufficient to identify the exact pathological changes causing the lameness. Despite conservative treatment, the condition of the horse deteriorated and the horse was euthanized after 15 days. A diagnosis was determined by post mortem CT examination and an autopsy of the affected limb. From several pathological findings, an acute cystoid lesion in the first phalanx communicating with the fetlock joint was determined to be the probable main cause of the severe lameness in this horse.