Bone is a phenomenal tissue that has the ability to change, grow and restructure itself based upon the loads we apply to it. Bone gives our bodies support and structure, it protects our many vital organs, and it acts as a reservoir for the important minerals we need every day.
A fractured bone simply is a broken bone. There are many sub-definitions of the term fracture. For instance, a compound fracture is an irregular fracture that has broken through the skin. A comminuted fracture is one that is in many pieces. There are any number of different varieties of fractures that we see in the foot.
Fractures can occur for many different reason. We tend to think mostly of trauma causing fractures but there may be other contributing factors. Most of us are familiar with the term osteoporosis. Osteoporosis means that the density of the bone, the mineral content so to speak, has been reduced. Patients with advanced osteoporosis are subsequently more susceptible to fracture. Bone tumors may also contribute to fractures by weakening the bone. And lastly, many other systemic or metabolic diseases may contribute to change in bone that may result in a fracture.
Stress fractures are quite common in the foot. A stress fracture simply implies that the load applied to the foot was greater than what the bone could tolerate, so it breaks. Load may be further define as the duration of load, the frequency of load or the amount of load. Also, the general medical status of a patient may play into the development of a stress fracture. Malnutrition, age, osteoporosis and a host of contributing medical causes may play a significant role in the ability of bone to heal, prior to and leading up to a stress fracture.
The most common stress fracture that occurs in the foot is in the metatarsal bones. These fractures are also referred to as march fractures. The name came about as the result of forcing young, sedentary army recruits to march 20 miles with a full backpack. Their transition from civilian to soldier was too abrupt resulting in a load that was greater than what the metatarsal bone could tolerate.
Other stress fractures that occur in the foot include calcaneal stress fractures (the heel), navicular stress fractures (medial arch) and cuboid stress fractures (the lateral arch). Essentially any bone, when put under too much stress, for too long a period of time can sustain a stress fracture.
Treatment of stress fractures
X-rays are necessary but aren't always so helpful with metatarsal stress fractures. In most cases, metatarsal stress fractures can only be seen on x-ray three to four weeks after they occur. X-ray findings of stress fractures are very subtle. We don't actually see the fracture, but we see the deposition of calcium surrounding the fracture as the bone heals. This finding is referred to as bone callus and is the body's own internal cast, so to speak. Computerized tomography (CT Scan) is helpful in defining some stress fractures. A stress fracture in some bones, particularly hard cortical bone, may create a fracture line that is sharp and clear on CT scanning. MRI's are also used to test for stress fractures. MRI's are particularly helpful in identifying areas a edema (swelling) within the bone that may be associated with a stress fracture.
The technique of treating stress fractures varies in each case but the fundamental principles are the same. First, we need to confirmed that the fracture is stable, well aligned and that the ends of the fracture appose each other. Once we've confirmed alignment and apposition, treatment is simply variation of rest. Treatment may include bed rest, a cast, a fracture shoe or just decreasing activity. As you can see, each of these methods of treatment is a variation of rest. Most stress fractures of the foot will heal over time with just a little help. How long? Patients are usually surprised to find out that stress fractures takes 8-12 weeks to heal.
