Horses and humans have a few things in common. We’re both mammals, we both love to eat oats (although we favor oats in cookie format while horses seem to like the grain in a rather less embellished form) and we’re both very, very stubborn. However, humans don’t really much care for grass as a food staple, and we have no tails to speak of. Also, we walk rather differently than horses. While they put weight entirely on their toes (the hoof is essentially one big toe), human feet are designed rather differently. So, when our feet start behaving in a more equine way, it can start causing serious problems.
Equinus may occur in one or both feet, and is a condition in which the ankle doesn’t bend upward properly. The normal range of motion for ankles is to lift about 10 degrees upward when you’re standing on a flat surface (i.e. when your feet are at a 90 degree angle to your leg). If you’ve got equinus, you may not be able to lift your ankle up that much, or at all. In very severe cases, your foot may even pull downward, making it difficult or even impossible for you to stand with your foot perpendicular to your leg.
Equinus may be caused by several different things, although the causes may be grouped into two categories: soft tissue or bone problems. Soft tissue problems usually center around tightness in the muscles and tendons that pull the foot downward: the calf muscles and Achilles tendon. Basically, these muscles may pull the foot back and downward (toward the heel) so strongly that they overcome the strength of the muscles pulling the foot back up. These tight muscles, tendons or ligaments may simply be congenital (present at birth), inherited (part of natural genetic variation), a symptom of a neurological disorder (like cerebral palsy) or may be a result of some external cause. Injuries (or surgery) may lead to scarring, which can tighten the tissue. Or, calves may tighten when they’re in a contracted position for a long time, such as when you wear high heels all day long (you know-those times when you really wish you’d brought those old, comfortable sneakers to work), or if you wear a cast that points your toe downward.
The causes aren’t always due to tight tissue, though. Sometimes there are bones blocking the ankle that keep it from moving upward fully. This may be due to a bone fragment blocking the joint (generally a result of trauma), or bones may become deformed by arthritis or tumor growth.
People with equinus are likely to have problems lifting up one or both feet (they may find it either difficult or impossible to do so). In severe cases, the foot may be permanently bent downward (toward the heel). This condition may sound kind of obvious, but people may be unaware that they have equinus. Milder forms of the condition may simply cause people to adjust their gait (usually they raise the heel up earlier than normal in the walking process, might make their arches flatter, walk on their toes, or change the way their hips or knees move) in order to make up for their inability to properly lift their foot. Because this changes where stress occurs on the foot (often the ball of the foot is hit the hardest), it can lead to a whole host of other problems.
For instance, if you develop equinus, you may begin to experience pain in the heel or arch (also called plantar fasciitis), painful ankles, an inflamed Achilles tendon (tendonitis), problems like calluses or even ulcers on the ball of your foot (particularly if you have diabetes), arthritis in the middle of your foot, or deformities such as bunions or hammertoes. There may also be problems further up your leg: you may experience shin splints, or cramps in your calves.
Despite the name of this condition, it’s totally unnecessary to see a veterinarian when you develop equinus. Your podiatrist, while probably not intimately familiar with horse feet, has plenty of experience dealing with the human variety, and is well trained in diagnosing such conditions. When you go in to see the podiatrist, he or she will likely see how far you can move your foot up and down, both while your knee is bent and while it’s straight. (This helps to determine where the problem lies: bone, muscle, or tendon.) The podiatrist may push slightly against your foot as you try to move it (but never fear-podiatrists don’t do such things to make the examination more difficult for you-this method helps to determine the true strength of the muscles).
You may also need to undergo some X-rays or other imaging process so that your podiatrist can fully understand what’s happening inside your foot. If he or she suspects your equinus may be due to an underlying neurological condition, you may be referred to a specialist for a neurological examination.
Once you’ve been evaluated, your podiatrist can discuss what’s caused your particular brand of equinus and talk about the treatment options that are best for you. Because equinus is often caused by tight calf muscles, adopting a regimen of calf-stretching may improve your condition. You can also help relieve stress on the calf muscle by wearing a splint at night to keep the muscle in the proper position. Some shoe inserts can also provide relief. Because the Achilles tendon is likely to be under some strain, lifting up the heel somewhat may prove helpful. Heel cups may be used to accomplish this, or wearing shoes with moderate heels might work as well for you (although you’ll want to discuss proper heel height with your podiatrist). Orthotics (prescription shoe inserts) might also be useful in correcting the way your foot bears weight. If a neurological condition is at the heart of your problem, that can be addressed separately.
If you come in to the office with a number of secondary symptoms (such as hammertoes, tendon pain, bunions, etc.), your podiatrist may treat these as well. Common treatments include (unmedicated) pads to relieve pressure (in the case of calluses), medications or treatments to reduce inflammation, and so on.
Surgery may be necessary if you’re still finding yourself with a foot that behaves more like a horse’s than a human’s, even after more conservative treatment. Surgery may be used to lengthen tight muscles or tendons, or may be the best way to remove a blockage of bone, if that’s the cause of your equinus. Whatever the treatment method, your podiatrist can discuss the options with you to get your foot to act fully human again.