cannon bone

anatomy

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June 22, 2026

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The cannon bone is a bone found in hoofed mammals that extends from the knee or hock to the fetlock. In horses, it specifically refers to the enlarged metacarpal or metatarsal bone of the third digit.1

Metacarpal bones are located between the wrist and the digits of the forelimb in land vertebrates. In horses, evolution has led to a reduction in the number of metacarpals, with one strengthened metacarpal bone forming the lower leg. The splint bones behind and above the hoof are reduced metacarpals. The principal bone enclosed within a horse's hoof is known as the coffin bone or pedal bone.23

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artiodactyl
Limb adaptations for fast running
…forelegs and hindlegs, respectively, forming cannon bones. The nearest approach to a cannon bone in the living Suiformes is the proximal fusion (i.e., at the upper ends) of the two central metatarsals in peccaries. Camels have front and rear cannon bones, but the fusion does not extend right to the…
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…forelegs and hindlegs, respectively, forming cannon bones. The nearest approach to a cannon bone in the living Suiformes is the proximal fusion (i.e., at the upper ends) of the two central metatarsals in peccaries. Camels have front and rear cannon bones, but the fusion does not extend right to the…
Read More