A stress fracture is a tiny break that develops in bone when the the ongoing repetitive loads on the bone a greater than what the bone is design to take. Obviously a sudden one-off high load will cause a complete fracture. Stress fractures are common in athletes and in military populations due to their higher activity levels. Stress fractures tend not to develop in these people if the bone is given time to adapt to the loads that are applied to it. This means that there needs to be a slow progressive increase in load and the repetitive stresses that get applied. If this is done slowly and progressively, the bone is given a chance to adapt to those loads being applied. One particular stress fracture, the navicular stress fracture, as a particularly problematic one in athletes. The navicular bone forms the top part of the arch of the foot so is subjected to a substantial amount of repetitive loading when participating in sport. This means that if the bone is not given a chance to adapt to those loads a stress fracture can occur. A unique diagnostic feature of navicular stress fractures is the pain is obviously in the navicular bone that in a small spot of that bone, sometimes called that ‘N’ spot. A CT scan or MRI can confirm the diagnosis. The reason for this particular stress fracture being so problematic is because it is in such a important weight-bearing part of the foot, a six-week rest, often in a cast is needed initially to get the fracture to heal. This is then followed by quite a lengthy and slow progressive return to sports activity. The athlete will be missing out on full training for quite some periods of time. If you think you have a navicular stress fracture then a podiatrist is often a good health professional to consult.