A Horse Leg Skeletal Anatomy Quiz

horse leg skeletal anatomy quiz

If you’ve been around horses long enough, you’ve probably heard that the horse has more bones than any other mammal. What you may not know is that the skeletal structure plays a large role in the horse’s movement, mechanics and efficiency. The horse’s bones are held together with ligaments and tendons; the way they work in relation to one another is determined by how well the bones are proportioned, and this is what determines the quality of movement a horse can generate and its ability to carry a rider.

The horse has two main types of skeletons, the axial and the appendicular. The axial skeleton protects the horses vital parts, including the skull and the ribcage. The appendicular skeleton supports the body, and includes the forelegs, hind legs and pelvis. Each leg is connected to the axial skeleton via muscles, tendons and a joint called the hock. The hock is one of the most important joints in the horse, and a good working hock is an indication of a healthy bone structure.

A horse’s hoof is composed of the wall, sole and frog (Figure 1). When pressure is applied to the hoof, the third phalanx, or coffin bone, transmits this pressure to the lateral cartilages, which flatten and push against each other and onto the digital cushion and frog. These structures are the primary shock absorbers of the foot.

Inside the hoof, a small bone called the navicular bone sits above the deep flexor tendon. A bursa, or fluid-filled sac that reduces friction between the tendon and the bone, is also located there. If this bone becomes compressed and irritated, it is known as navicular disease, a common cause of lameness in horses.

A mare’s gestation period is approximately 11 months. During this time, she is expected to produce about four foals each year. One of the first signs that a mare is ready to foal is when she starts “waxing up.” The term refers to a thick, clear liquid that appears on her teats.

Correct leg set is the combination of a foot under each corner of the horse’s body, accompanied by adequate, straight bones with short cannons; long, correctly sloped pasterns and medium-sized, balanced feet. A horse with a correct leg set is able to carry its weight through the hind feet and transfer it to the front feet during gaiting and other movement, resulting in good movement and stability.