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Inflammation of the navicular bone and surrounding structures in the horse; it is marked in the beginning by intermittent limping, followed later by atrophy and stiffness of the muscles of the chest and shoulder, or chest founder, caused by the unnatural gait.

Disease of scaphoid bone.

In the horse, inflammation arising from a strain of the strong flexor tendon of the foot, where it passes over the navicular bone-a boat-shaped bone [L.], the upper of two rows of the carpus [L.].