SHIN SPLINTS

(Lower Leg Problems)

By Dr. Alan Gjedsted MD

• Shin Splints are the bane of many a runner. They present as pain along the front,inside or outside of the lower leg and almost always occur in sports involving running or jumping, such as jogging, dancing, gymnastics, etc. Contrary to popular lore, they do not always represent a “stress fracture” of the shin bone (tibia), although, stress fractures can be one of the reasons for lower leg pain.

• There are 3 main causes for "shin splints" - the Medial Tibial Stress Reaction; the Stress Fracture; Chronic Compartment Syndromes. This website will deal primarily with the two most common types: Medial Tibial Stress Reaction and Stress Fractures.
• The first (probably, the most common) type, is known as "Medial Tibial Stress Syndrome (MTSS)". The symptoms and signs of this type of Shin Splint are somewhat variable, but in general, it causes pain and swelling along the inside, lower to middle of the tibia (the big shin bone you can feel), about 4-6 inches above the ankle. You might notice that there is an area of tenderness extending over a relatively large (more than 1") portion of the bone and there may be accompanying swelling and even redness. This type of shin splint will initially cause pain that begins after your workout, but, with time, cause pain during your workout and, ultimately, during times of rest and with normal, everyday activities. The pain of MTSS is often worsened by standing on your toes or pushing off, as in the picture of the sprinters, above. Causes of this, and other types of Shin Splints, are listed below.
• Another, less frequent, type - Stress Fracture, can occur in any part of the shin or lower leg, but most commonly occurs along the front of the tibia just below the knee, just above the ankle, or right near the middle of the shin. It can also effect the other bone of the lower leg, the Fibula, where it causes symptoms on the outside of the leg, above the ankle. This type of lower leg problem, will more commonly cause a local area of pain, swelling, redness and tenderness (often less than 1-1 1/2 inches total), initially beginning while exercising and going away with rest. This will progress to pain that even occurs at night.
• The third type of "shin splint" is called Compartment Syndrome; it begins as pain, usually in the middle of the lower leg, on the outside/front, that begins at a certain point in your exercise routine, goes away with rest, but recurs at about that same point the next time you exercise. It can cause a sensation of numbness in the foot, as well. Sometimes, it can progress to where it causes persistent symptoms, but this is unusual. It can sometimes be made worse by curling your toes up or bending your foot up against some resistance.

CAUSES

There are a number of causes for Shin Splints. They vary somewhat by the type of problem (i.e. MTSS vs. Stress Fracture vs. Compartment Syndrome).

The most common causes are:

1.A change in the activity/exercise you are doing.

2. A change in the intensity of the workout (i.e. longer distance, longer workout times).

3. The type of exercise you do - running in sprints, on a track, uphills, jumping, repetitive impact exercises.

4. The shoes you are using.

5. The surface on which you exercise.

6. You particular body type or "anatomy". Such factors as: Fallen Arches (flat feet), Knocked or internally rotated knees, very high arches and others are all prone to cause this problem.

For the Medial Tibia Stress Syndrome/MTSS, things like shoes (too old shoes, new, but different shoes, shoes that don't provide enough motion-control or shock absorption), type of exercise (running and pushing off exercises are the worst), type of surface or running you do (?on a track, ?uphills), and your own personal anatomy (fallen arches or "knock" knees) seem to be the main causative factors. The common factor to all these things is a repetitive use and "pulling" of the muscle attachments along the lower leg, particularly those muscles that make your foot "pushoff" or lift the heel from the ground. It is felt that this type of shin splint represents an inflammation at the bony attachment of these muscles (periosteum), along the inside of the tibial (shin) bone; see Lower Extremity

For Stress Fractures the main causes are repetitive loading on a hard, ungiving surface, frequently from increasing mileage while running on concrete or roads (e.g. are you training for a marathon when you are used to doing 10k's?). Shoes (not enough shock absorption, old & worn), anatomy, type of sport (?gymnastics, ballet, dance) are all important factors, as well. It is well known that Stress Fractures are caused by repetitive loading and bone breakdown in a specific spot. Normally,this occurs with every step we take and our bodies are able to repair whatever breakdown occurs rapidly and without any problems (i.e. repair equals breakdown). However, when we overwhelm our body's ability to repair this ongoing breakdown process (where breakdown exceeds repair) by radically increasing our mileage, changing our running surface or style, or just taking up a new, novel type of sport, we can potentially cause our bones to "fail" and begin showing signs of failure with very minute "cracks" called stress fractures. If we ignore these signs, continue to run thinking it will go away with time, these can progress to a full thickness fracture, even requiring a cast in order to heal.

Compartment Syndromes, are almost always caused by those things that cause your lower leg muscles to get bigger, such as walking, running, etc. The cause for this problem is your muscle getting larger with exercise at the same time it is being compressed by the firm, fibrous tissue it is wrapped in (Compartment), causing pressure on the muscle, then the blood supply and the nerve supply. In the worst cases, this can be a problem requiring surgery to fix. Luckily, this is quite rare in everyday recreational sports athletes.

Special mention needs to be made concerning worn out shoes as a “hidden” factor in shin splints. We must always keep in mind that, although the soles and the tops may appear fine, running shoes begin to lose their ability to control pronation and absorb shock after 400-500 miles. You should calculate how long it takes you to run this distance (e.g. divide 400 miles by the number of miles you run per week and you have how many weeks your shoes will last), then be sure to replace your shoes before this time. Stick with those shoes you know have worked for you in the past when buying new shoes and I usually recommend that most novices, who are not sure of what is the best shoe for them, go to a "real" running shoe store (in San Francisco: On the Run [9th Ave], or Fleet Feet [Chestnut Street]), to get their shoes as these places specialize in runners and their problems.

Speaking of shoes, most people with this problem should, when looking to buy running shoes, ask for shoes with good “Motion­control” properties, to prevent the excessive pronation, as over-pronation is a frequent finding in runners with the most common type of shin splint, MTSS. Runners with really flat feet may require shoe inserts, Orthotics, to control their pronation. Also 2 pairs of shoes used alternately will last longer than 3 pairs used sequentially. Keep a log of the miles on each pair so you know when to replace.

MAKING THE DIAGNOSIS

Making the diagnosis of this troubling and potentially chronic problem can be a task in itself. My feeling is that, unless you are very sure of your ability to tell one type of lower leg pain from another, you should let a skilled professional (your doctor, trainer, physical therapist) help assist in making the correct diagnosis. Although the treatments for all three causes of Shin Spints can be similar, knowing exactly what the underlying problem is and when to move to the next diagnostic test or level of treatment is important. For instance, persistent training on a Stress Fracture may cause a long term problem, including a failure to heal and the need for a full cast, or even surgery; "running through" the pain of a Compartment Syndrome can lead to nerve or muscle damage, which may not be reversible.

In general, the diagnosis of these problems is 90% by history and physical exam, in the experienced provider. Tests that may need to be done would include: regular Xrays or a Radio-isotope Bone Scan, which can show Stress Fractures when not seen by Xray. In most cases, other tests, such as MRI, CT Scan, or Arthroscopy are either not necessary or of no help in the diagnosis.

 

TREATMENT

 

1. Relative Rest

This is the first mode of treatment for all the types of Shin Splint, no matter what the cause. "Relative Rest" does not mean you must stop running or stop exercising, as you will see below.

If you are an “everyday” runner, limit your running to every other or every 3rd day and stop short of causing pain. If this is only 1/4 or- 1/2 mile that’s OK. It depends upon your mileage and what you are used to. If you have been able to run pain free and the symptoms are improving then after 2 -3 weeks you may increase the distance. If you are unable to even walk without significant pain, then an alternative exercise will be needed until you are improved enough to begin running again.Occasionally, athletes will allow these problems to progress to the point where any weight bearing activity (going to the bathroom, getting up from a couch) causes significant pain. In those circumstances, a cast or brace, along with crutches may need to be employed.

Gradually increase your distance/mileage/duration of workout: Start with a shorter distance than you know you can comfortably run (maybe 1/2 to 1/4 the distance you’re used to) then increase no more than a 10% per week (e.g. If you are running 10 miles a week, then increase by 10%, or 1.0 mile/week, or 10+l miles/week=11 miles). If the pain returns rest 2-3 days and then resume at the prior level where you were running pain free. You need to keep a log book to chart and monitor yourprogress. Begin by using the “Stretch-Walk-Run-Walk-Stretch” technique.

Most people make the mistake with overuse injuries of quitting entirely for many weeks and then attempting to do the same distances that got them into trouble the first time. Remember, the human body is truly remarkable in it’s ability to adapt, BUT it really prefers to adapt to gradual changes over time. Eventually with slow steady progress, your muscles, tendons and other soft tissues will adapt to the stresses you are asking of it.

For those persons unable to do any running without bringing on the pain, “Water running” is a very good way to rehab running injuries. You use a flotation device and run in the deep end of a pool. You can move to the shallow end, running on the bottom, as your pain begins to improve. Cross-training, or Alternative Training is a very good way to keep active and in shape while you rehab this problem. Any sport not requiring the usual muscles of running or pushing off and doesn't require repetitive loading or impact to the lower extremity is fine: swimming, cycling (especially stationary cycle), Stairmaster.

2. Stretches

These must be done both before and after exercise.

The stretches for shin splints are as follows­

A.Gastrocnemius stretch - place the leg back, keep the heel on the floor, knee straight, and gradually lean forward against a wall until you feel a stretch or pull in the mid to upper calf muscle. Hold for 10 - 30 seconds, repeat. Do not overstretch to the point of pain, and do not bounce.

B Soleus muscle stretch - place the foot forward, bend the knee about 90 degrees and lean down putting weight on the foot. Your knee should be directly over the toes, and you should feel a stretch in the bottom part of the calf -- just above the Achilles tendon. This stretch is particularly useful for posterior shin splints. Often this stretch will cause pain in the “shin splint” area.

C. Hamstring stretch- while standing, place your foot up on something at about hip height. Keep your knee straight and slowly bend forward, until you feel the stretch in the back of the thigh.

D. Peroneal stretches. Bend your foot inward and down, stretching the muscle that runs along the outside of the calf, along the fibula bone.

3.Orthotics

As I mentioned before, many runners with this problem have some degree of excessive foot rotation/pronation. One way to prevent this (along with Motion-control shoes) is by adding a shoe insert that supports the arch and keeps it from falling inward with each running step. There are many makers of these over-the-counter arch supports, too many to list here. Spenco makes a 3/4 length plastic running shoe Orthotic that will provide extra arch support. These cost approximately $20 and are available in a lot of running shoe stores (e.g.. Fleet Feet, On The Run, Big 5, Coplands). Some places even offer a service of custom making a small orthotic to fit your foot only, right in the store. Call around and take your running shoes in to make sure they fit. Be sure to ask for a type with the plastic or hard support base, as the high-density foam type tend to lose their support rapidly. Runners with flat feet need extra stability in their running shoes. There are running shoes that have stiffer heel support to prevent over­pronation (ask your shoe salesperson) and the arch support Orthotic should help.

Sometimes more specific orthotics are required, especially in runners with very pronounced deformities, such as flat feet. These can be made based on a mold of your foot and are done through a podiatrist’s office -- especially one with experience in sports medicine. Attached to this sheet is the name of such a podiatrist. These are not a covered Kaiser benefit, but we can recommend where you might have these done.

4. AntiInflammatory Meds

These can also used to treat shin splints, but do not expect full relief from the medication alone. One common example is Ibuprofen (Advil, Motrin); another is Naproxyn (Alleve, Naprosyn). Usually these medications are taken for 2-4 weeks until the acute inflammation subsides. DO NOT TAKE IBUPROFEN OR NAPROXYN if you are allergic to it or to aspirin, or have any medical condition or problem,such as ulcer disease or kidney disease, which precludes the use of these medications. Anti-inflammatories have been shown to irritate the stomach, and can cause ulcers and kidney damage in a small percentage of people who take them. We usually recommend that athletes do not rely on medication and medication is not a substitute for the other steps outlined above. It may be necessary, but is usually only used for 2 -4 weeks. It is best to avoid any medication if possible.

5. Ice

Ice can be very helpful during the acute phases of your pain. This is especially true of those Shin splints with redness, localized tenderness or swelling. Use an Ice Massage, holding the cube in a washcloth and rubbing the swollen, sore area for 10 to 15 minutes. You can also make special ice massage applicator by filling a small Dixie cup with water, freezing it, then tearing away the top 1/2" or so of the cup, giving you a place to hold the cube (the remaining bottom of the cup) and a nice, round, regular surface of ice to apply the massage. Frozen peas or corn (in a bag) can be useful for more general ice/cooling applications. Remember not to exceed 10 to 15 minutes each time, and always wrap any applied ice in a towel or washcloth (especially true of the gel-ice you can get at the store), as it is easy to cause burns and frostbite with too vigorous application. You can repeat icing every few hours as needed.

 

REMEMBER: These are general guidelines for self treatment of Shin Splints. The problem is your own bodies inability to cope with the stress of running that you are placing on it. It will take time, sometimes weeks or months, for the problem to resolve. Do not expect miracles. Do not try to “run through” the problem. Stop when your body tells you to. Trying to tough it out can lead to long term pain and disability and, not infrequently, to Stress Fractures of the bone and, even “true” through and through fractures, requiring casts. If you are not improving with this home treatment, if you worsen significantly, or if the pain becomes a continuous discomfort, even at rest, return to be rechecked by your medical provider.