The purposes of this large three-part study were to establish which clinical features were more likely to be seen in horses with caudal neck problems compared with control horses, and to relate these to the presence of the congenital variants of the sixth and seventh cervical vertebrae and other radiological abnormalities.
The two-centre study was restricted to all Warmblood horses evaluated consecutively at UC Davis, California in the USA and at the Animal Health Trust in the UK over a two year period. All horses were examined using a comprehensive predefined protocol by two experienced clinicians, Professor Monica Aleman and Dr. Sue Dyson. Systematic, standardised clinical assessments were performed to assess posture, muscle development, range of motion, reaction to palpation and movement patterns in all gaits in-hand and on the lunge and when appropriate also ridden. Additional tests, such as walking up and down steps or blindfolding, were performed in selected horses to assess neurological dysfunction.
There were 96 case horses and 127 control horses. Cases comprised horses with neck pain or stiffness which was not explained by other problems unrelated to the neck, those with forelimb lameness attributable to the neck, or those with incoordination and weakness (ataxia and proprioceptive deficits) consistent with compression of the spinal cord in the neck region.