Stress fractures. These are probably one of the most two dreaded words any athlete could hear. But what exactly is a stress fracture and how are they caused? Are some people just doomed to get these menacing injuries repeatedly, or is there a way to avoid them? I, myself, being a long distance runner and victim to stress fractures for over two years, have been wondering these same questions. Now, I have the answer to them.
Every day, our bones are attempting to repair themselves. They are constantly remodeling themselves, especially during a sport when excessive stress is applied to the bone. Over time, if enough stress is placed on the bone that it is higher than that of the remodeling, a weakened site on the bone may appear A.K.A. a stress fracture. When your bone remodels, it becomes more porous, which would explain the weakness of the bone. A stress fracture is a very small sliver or crack in the bone that is accompanied by intense pain. For every mile a runner runs, more than 110 tons of energy must be absorbed by the legs, so why can't our bones stand that much energy? Our bones are not made to stand that much energy on their own. That's when the muscles come in to play. As we run, our muscles become tired and stop absorbing most of the shock like they're supposed to. Finally, your muscles (usually in the lower leg) become so fatigued that they stop absorbing any shock and transfer it all to the bones. So there are two main contributing factors to the cause of a stress fracture; too much too soon and weak muscles. Now that we have tackled two of the causes, what can we do about them? First, a widely known rule about increase in mileage is about 10% increase per week. I know that this is probably one of the most difficult rules to follow. I always wanted to just go out and start running five or six miles, but that's just asking for an injury. A 10% increase is the best way to go. Also, strengthening exercises also help build more muscle strength in your legs. If you strengthen your muscles, it will stop them from getting fatigued so quickly, which allows them to absorb the pounding of running for longer periods of time. Key muscles that need to be strengthened with lower leg stress fractures are the calves and the shin muscles. Another method of avoiding stress fractures is by adding more stress to the bones. This may seem a little absurd, given that stress fractures are caused by stress on the bones, but the stress that is placed on the bones when a stress fracture occurs is too great. When some stress is applied to the bone, they become stronger and less susceptible to a stress fracture. Structural units of compact bones (bone of the arms and legs) are osteons. Osteons are basically hard, elongated, cylindrical groups of cells that run vertically along the bones. When stress is placed on the bones more of these osteons are placed on the bone causing it be less susceptible to injury. Another way to think about this is by picturing a toothpick. If you have one toothpick balanced vertically and you drop a brick directly on top of it, it will break easily. The toothpick represents an osteon while the brick represents the force of running. Now picture 100 toothpicks all bundled together balanced vertically. If you were to drop a brick on these toothpicks, they would be much less susceptible to a break. This would explain why a 10% increase in mileage is recommended for runners. It allows your bones to adapt to the added stress, so they are able to withstand greater amounts of stress in the future. It is also wise to watch your calorie, calcium, and vitamin D intake. When performing any exercise that applies more stress to the bones, it is wise to up your calcium and vitamin D intake greatly. It is important to monitor what you eat because nutrition plays a vital role in bone development. It is also wise to take a calcium supplement to maintain strong bones.
Stress fractures usually have a narrow list of symptoms. It includes a generalized area of pain, increased pain when pressure is applied, and pain with weight bearing. Usually when running, a stress fracture has severe pain in the beginning of the run, moderate pain in the middle of the run, and severe pain at the end and after the run. Usually, a bone scan is performed to test for a stress fracture. X-rays usually do not show any evidence of stress fractures.
There are many types of stress fractures. One of the most commonly known is a tibia stress fracture. The tibia is a weight bearing bone and therefore when a stress fracture occurs on it, it takes much longer to heal. Another common type occurs in the metatarsals of the feet. These also take quite a while to heal because the feet are constantly facing weight. Another type of stress fracture is known as the fibula stress fracture. The fibula is non-weight bearing bone and therefore when a stress fracture occurs on it, it takes less time to heal.
Now that we know what causes a stress fracture and of the different types, its time to talk about the ways to help heal a stress fracture. The first and most effective way is rest. A word that all runner's cringe at...rest. Rest is only way to completely heal a stress fracture. The average time of complete rest from the activity that caused the stress fractures is six to eight weeks. During those weeks, it is advised to cross-train as an attempt to keep your cardiovascular base. Another practice that is becoming more common is the use of an electronic stimulator or bone stimulator. These devices send electrical impulses into the bone to promote healing, but how on earth does electricity help a bone heal? Recent studies have shown that the bone heals naturally via electronic signals. So, it you add more electronic signals into the bone, it causes the bone to lay out more bone cells which strengthen the bone. It is also advised to wear a hard plastic boot to take some stress off the stress fracture. If the stress fracture is severe enough, crutches also help to take all stress off the bone. Another way to help heal stress fractures is an Air cast. These Air casts have pre-inflated cells that put light pressure on the bone. They are incredibly light and feel as if you were not wearing it. These Air casts promote healing by increasing blood flow to the area. When I got my stress fracture, I used an Air cast to finish off my Cross Country season and found that it helped me greatly. It takes away a lot of the pain because of the pressure it applies to the bone.
Stress fractures. They really are the worst two words any runner could hear. However, there are ways to avoid this pesky injury by just following a few simple steps. Remember, stress fractures are mainly caused by overuse, so take it slow and take every precaution possible to avoid it.
