The hock is perhaps the most complex-and most important-joint in a performance horse’s body.
No hocks, no horse. it’s as true as no hoof, no horse.localriding.com
This backward-pointing knee is actually the anatomical equivalent of a human ankle.
You can see this if you look at yourself sideways in a mirror and bend all the joints of your leg, while resting your big toe on the floor.
Your horse stands on one toe (concealed in the hoof); your foot is the lower leg or cannon bone and your backward pointing heel is like the horse’s hock.
Your horse’s knee is actually the stifle joint, which points forwards just like ours.
Like your ankle, the horse hock is made up mostly of bone and tendon; the muscles that flex and extend it are in the upper leg.
Since a horse’s main motive power comes from the hindquarter, the thrust developed by those big muscles must be transmitted through the hock to the hoof. The hock must be big enough, massive enough, to take that thrust without injury.
- Look at a picture of a showjumper starting a jump, you can see the thrust that must come from the hindquarter through the hock to push the horse off the ground.
- Look at a picture of a dressage horse in collection, again you can see the thrust that enables short, elevated strides.
Buying a horse …
If you’re looking for a horse for performance riding-jumping, endurance, eventing, mountain riding, any speed or agility work … look for a horse with excellent hocks.
Some horses have undersized hocks, and develop strains and even tendon ruptures in the hock because they develop more power in the hindquarter than their hock can handle.
No matter how powerful the motive muscles are, if the hock cannot handle the strain, the horse cannot run, jump, suddenly change direction, or do collected movements without risk of breakdown.
Undersized hocks can result in back problems, especially in the loin coupling, as the horse tries to reduce
hock discomfort by using its back inefficiently.
From the rear, a good hock appears rectangular, bony, and large enough for the size and weight of the horse, without lumps
or swelling to either side. It should be distinctly wider than the cannon below, rather than wedge-shaped (narrowing downward).
From the side, it appears clean, bony, with no lumps above or below it.
One good test of a Horse’s hock function is to lift the hind hoof and flex the leg snugly for a few seconds, then let the leg down and immediately ask the horse to trot forward in hand.
If the hock is sore, the horse will "gimp" a few strides, often with exaggerated flexion in that leg.
When the horse walks away from you in a straight line, the movement of the hock should be forward and back and should not wobble to the outside or inside when that foot is on the ground and the horse’s full weight is on it.
- An outward wobble as the weight passes over it suggests hock weakness.
- Lumps and soft swellings around the hock are a danger sign and require a veterinarian’s evaluation. Some may be the result of injury not related to conformation, but only your vet can rule on that.
Some breeds were small feet are considered desirable, tend to have consistent hock problems.
When breeding for small feet, the entire lower leg may be too refined and the hock may look wedge-shaped from behind and slender rather than boxy from the side.
In movement, these horses may stand cow-hocked or have a hock-wide stance to protect their hocks. They are likely to have that tell-tale wobble to the side when weight passes over that leg.
With all the leg bones in correct alignment, the whole thrust is not being transmitted down to the hoof. Rather some of it is forcing the hock sideways.
Horse Hock ConformationAny breed can produce a horse with undersized or under-strength hocks, so if you’re interested in a performance sports horse, make sure you look at the hocks before you look at the color, the height or that pretty head.
Horses with inferior hocks may be fine for lower-level dressage, hacking or pleasure riding, but only if your pleasure riding is quiet, relaxed and simply ambling along undemanding tracks