Navicular bone osteomyelitis and navicular bursitis with associated fistula diagnosed with magnetic resonance fistulography in the horse

Abstract

Summary A 7-year-old Quarter Horse gelding was referred for magneticresonance (MR) imaging due to chronic left hindlimb lamenesslocalised to the foot. On presentation, a previouslyundiagnosed draining tract was identified at the plantaraspect of the pastern. Radiographs revealed severe osteolysisof the navicular bone. Positive contrast MR fistulography wasperformed using a gadolinium based contrast agent followingconventional MR imaging of the left hind foot. Fistulographyallowed characterisation of a fistulous tract, which was closelyassociated with the deep digital flexor tendon, navicular bursaand osteomyelitis of the navicular bone. History and clinical findings A 7-year-old Quarter Horse gelding was referred for magneticresonance imaging (MRI) of the left hind foot for theinvestigation of intermittent lameness of 3 months’ duration.Recurrent subsolar and coronary band abscesses werediagnosed by the referring veterinarian. Treatment prior toreferral included debridement of devitalised tissue fromboth the sole and coronary band, oral administration ofnonsteroidal anti-inflammatory medication, oral administrationof antibiotics, and administration of antibiotics by regional limbperfusion.At presentation, the horse was