How One Bad Turn Leads to Another

Have you ever wondered why, whenever you sprain your ankle, it’s always the same one?

It’s no coincidence: The biggest risk for suffering an ankle sprain is having had one already.

The reason for this is a little-known phenomenon known as proprioception. This tongue twister of a term refers to a human body’s intuitive ability to know where it is in time and space without directly looking, like being able to walk a straight line without looking down. It’s a fine-tuned coordination that each of our joints has, an innate ability to instantly shift the body in an unconscious and instantaneous course correction to keep it centered.

It affects the performance of all of the joints in the body, although we rarely are aware of it. We may glance down when shaking someone’s hand, for example, “but the professional handshake is perfected when you look someone in the eye,” says Dr. Glenn Pfeffer, a San Francisco orthopedic surgeon. “Can you imagine what would happen if every time we went to shake someone’s hand, we missed?”

Some people are better at it than others, just as with any natural physical skill, and this ability can diminish with lack of use--such as when someone breaks a bone and spends weeks or months in a cast. Tightrope walkers, long jumpers, ballet dancers, cross-country runners, for example, have heightened proprioception.

These athletes and artists perfect these intuitive skills through high levels of training for their sport, or their craft. But proprioception is an ability that actually develops in early childhood. “Watch a 1-year-old learn to walk: He looks down at his feet,” Pfeffer says. “We, as adults, don’t do that because we have developed our proprioception.”

So what, then, does this have to do with ankle sprains?

While every joint in the body is affected by proprioception, it plays an especially important role in weight-bearing joints such as ankles or knees. “The hands and arms don’t have joints that control your full body weight, unless you are doing handsprings all the time,” says Dr. Nicholas DiNubile, a Pennsylvania orthopedic surgeon who is a consultant to the Philadelphia 76ers basketball team and the Pennsylvania Ballet.

Moreover, it is a key factor in whether, once injured, we are prone to re-injure those same joints again.

Every ligament in your ankle has thousands of nerves, and every time you hit uneven ground, a curb in the street, a crack in the sidewalk or a branch snaking across a hiking trail, your brain performs millions of calculations to ensure that your foot lands properly.

When you sprain an ankle, the key nerves that regulate this process are damaged, altering the body’s ability to perform this function. As a result, if you don’t do something to retrain those injured nerves, you’re more likely to sprain that same ankle repeatedly.

What we think of as a floppy or loose ankle that results from the first sprain is actually a slowdown in the feedback loop between the nerves in the foot and the brain. The brain can’t react quickly enough to prevent that ankle from being re-injured.

When the already vulnerable foot lands unevenly, and the ankle starts to turn, the proprioceptors--the part of the nerves that tell the ankle where it is in time and space--send a message, in effect, to the muscles: “Go back, go back.” But often the message comes too late, health experts said.

The foot doesn’t know quite where it is when it plants on the ground, and can’t adapt to variations in ground surface.

And a vicious cycle begins. This is one of the reasons ankle sprains are among the most common injuries afflicting Americans, even among people who don’t regularly engage in sports or other exercise. About 27,000 ankle sprains occur every day in this country.

An ankle sprain can happen during routine activities, such as stepping off a curb, just as easily as during exercise, particularly among those with earlier sprains. Sometimes the cause is not apparent. The ankle turns, and the person falls, utterly baffled as to exactly what he or she did to cause the sprain.

The ankle joint is made up of bones held together by ligaments--think of how a hinge keeps a door connected to the wall. In a mild sprain, the ligaments are just strained or stretched; with a moderate sprain, they are partially torn. And in the worst case, a severe sprain, the ligament is completely torn and no longer able to control the ankle joint.

The vast majority of ankle sprains are inversion sprains, meaning the foot turns inward, injuring the ligaments on the outside of the ankle. This occurs because of the way the ankle is built.

“The muscles on the outer part of the leg tend to be weak; there is a large muscle imbalance between the muscles on the outside of the leg versus the muscles on the inside of the leg,” says Janet Sobel, a Chevy Chase, Md., physical therapist who treats many athletes. Because of this, she says, “if it’s going to sprain, it’s usually going to turn in.”

Treating an Injury

Unlike with other injuries, you will know instantly when you sprain your ankle. Very quickly, you will have pain, swelling and tenderness. You may or may not be able to walk on it. If the pain and swelling are minimal, and you are able to put weight on it, you probably can treat it yourself at home. If your ankle is grossly swollen and painful, and the skin discolored, don’t put any weight on it, and seek medical attention immediately.

Ice treatment is the critical first step. Appy ice within a few minutes, or sooner, if possible, and certainly within 30 minutes.

This will reduce the pain and swelling. Ice it as often as possible on the first day for 15 minutes on, and 15 minutes off, and for days after if swelling persists.

Some experts believe that, after the first day, a combination of hot and cold treatment is preferable: ice to treat the inflammation, and heat to promote circulation and healing. This can be inconvenient and cumbersome. Sobel emphasizes that ice is more important. Also, gently moving the ankle will get circulation to the area just as effectively as heat.

DiNubile agrees: “As long as there is swelling and bruising, stick to ice.” The rest of the longtime formula known as RICE (“I” is for ice) still applies here: Rest, compression, elevation are also useful during the first few days following an ankle sprain. Put your foot up to help keep the swelling down.

“You want your toes higher than your nose,” DiNubile says. “You want your foot as high as possible. Also, I would wrap it right away. I usually put ice in the Ace wrap.” Don’t go back to sports too soon. But easy walking, as soon as you can bear weight, is essential for proper recuperation. Start with crutches if you cannot bear full weight; an ankle brace that stabilizes the ligaments but allows you to walk is also valuable. Also, as you recover, it is important to perform Achilles stretches to keep the tendon from becoming too tight.

‘Ankle Neutral’ Position

Ligaments heal best when kept in “ankle neutral” position, in which the foot is flat, and neither turned in nor out, nor up nor down, says Dr. Thomas O. Clanton, an orthopedic surgeon at the University of Texas Medical School in Houston. Another proper healing position is dorsiflexion, in which the foot is flat with the toes bent slightly upward.

“This position is better achieved bearing weight than without,” Clanton says.

The worst position for a healing ankle is non-weight-bearing, where the foot just hangs down (known as plantarfexion) because torn ligaments will heal in a stretched position, making it difficult to regain full ankle motion, he says.

But if walking or other weight-bearing results in more pain or swelling, stop and see a physician.

A mild sprain can take 10 or more days to heal, and more serious sprains as long as eight weeks. “You’re really about 75% back when you think you are 100%,” DiNubile says. “You probably still don’t have all your mobility, or strength or endurance or agility.”

Doctors offer various tips for knowing when an ankle is ready for action. Some suggest trying a skier’s stance: If you can’t get all the way down in position, the ankle probably needs more time to heal. Or if you can’t hop on the injured ankle three or four times without pain, it’s best to hold off on returning to sports activities.

Once an ankle has been sprained, especially for the first time, the most important thing to prevent repeated injuries is exercises to strengthen the ankle muscles and retrain--or re-educate--the proprioceptors.

Health professionals recommend a series of strength and balance exercises, including exercises on a BAPS board (a sophisticated wobble board like the ones kids play on), standing and hopping on a mini-trampoline, agility drills and jumping rope.

If you don’t own a BAPS board or mini-trampoline--and few people do--there are exercises that don’t require equipment. The idea is to put minimal stress on the injured ankle at first, then gradually increase the activities to strengthen the area.

Agility drills involve such maneuvers as shuffling side-to-side, walking backward and running. (Running a figure-8 pattern is helpful, beginning with wide loops and progressing to tighter loops as the ankle strengthens).

Other exercises include sitting with your legs crossed and placing a 2-pound weight (to start) on your foot. Bend your foot up and out, that is, away from the big toe. Do three sets of 15 repetitions. As it gets easier, increase the weight and the reps.

Another exercise: Lie in bed on your “good” side, with the injured foot hanging over the edge of the bed, with the weight on the foot. Turn your foot up and then slowly lower it.

You also can use resistance equipment, such as a Thera-Band, which is elastic tubing that can be wrapped around the bottom of the foot as you do the bending and pulling repetitions. This should help strengthen the peroneal muscles, the major muscle groups that support the ankle.

Also, balancing on one leg--the one with the injured ankle--is one of the best ways to regain proprioception. “Stand on the bad leg only, and try to balance on that leg,” recommends Sobel, the physical therapist. “If that’s easy, do it with your eyes closed. Do it for a minute. If that’s easy, stand on a pillow, which is a mushier surface,” she says. “If that’s easy, do it with your eyes closed.”

And if that’s easy, she says, you’re probably healed. Go out for a run.