Long‐term outcome of a non‐reducible congenital atlanto‐occipital subluxation in a warmblood foal

Summary An 11‐day‐old warmblood colt was referred to the Large Animal Teaching Hospital, University of Copenhagen, for further investigation of a stiff neck and lateral deviation of the poll, with suspicion of a congenital cervical vertebral abnormality. This case report describes clinical presentation, diagnostics, treatment and short‐ and long‐term outcome at 4 years of age of a horse, which was eventually diagnosed with congenital atlanto‐occipital subluxation. Attempts at reduction of the subluxation through closed and open approaches were unsuccessful, and a computed tomography scan performed at 4 years of age showed persistent subluxation, yet the horse was in full work and showed no lameness or ataxia.