A navicular stress fracture is a small crack or break in the navicular bone of the foot. The flat bone is located on the top of the foot, just underneath the crease made by the ankle when crouching. Stress fractures in the feet are most likely to affect athletes who play high-impact and running-intensive sports, such as soccer, basketball, and track and field. A navicular stress fracture may not be immediately noticeable following an injury, and the break can worsen over time with ongoing activity. It is important to visit a doctor at the first signs of foot pain so he or she can check for a fracture and explain treatment options.
Navicular stress fractures in athletes occur due to constant running, jumping, turning, and stopping. Dancers are also highly susceptible to foot fractures, as are military recruits who are put through intensive training regimens. The risk of fractures increases when a person does not thoroughly stretch and warm up before engaging in activity. Physical conditions such as osteoporosis rheumatoid arthritis, or a mild physical deformity where one leg is slightly longer than the other can also contribute to a navicular stress fracture.
Many people are unaware that they have suffered stress fractures in their feet until several weeks or months after the initial break. In the early stages, foot pain tends to worsen during activity but improve with rest. Eventually, pain worsens and becomes more persistent, and mild swelling may occur.
A doctor can usually diagnose a navicular stress fracture by evaluating physical symptoms and taking diagnostic imaging scans of the foot. He or she can identify the exact location of pain and tenderness by pressing on the foot in different places. When the patient reports pain above the navicular bone, x-rays and computerized tomography scans are taken to closely inspect the area. Treatment decisions are made based on the size and exact location of the fracture.
Most patients who suffer stress fractures are fitted with hard foot casts and instructed to avoid bearing weight on the affected leg. A person can expect to be on crutches for about four to six weeks, at which point the doctor can remove the cast and re-evaluate the injury. If the bone appears to be healing correctly, guided physical therapy sessions for several months can help the patient gradually rebuild foot strength and flexibility. Surgery is rarely needed for a navicular stress fracture, but a recurring or persistent condition may require the navicular bone to be permanently fused together.