Navicular stress fractures are a common foot injury in athletes. These stress fractures tend to occur in athletes whose sport requires explosive movements and sudden changes in direction. Commonly injured athletes include runners, jumpers, sprinters, basketball, and soccer players.
Why They Occur
The navicular bone is designed with a few problems that make it particularly susceptible to stress injury.1 One of these problems is the location of the bone. Located in the middle of the foot, high compressive forces are focused on this bone, particularly when the foot strikes the ground.
The second issue is the blood supply to the bone, particularly the central area of the bone where these stress fractures tend to occur. This area is located in a so-called watershed zone where the blood supply is less robust, making the healing of minor injuries more difficult and therefore more of a likelihood of progression to a stress fracture.
Signs of Injury
Athletes typically complain of vague midfoot pain just past the ankle joint. The pain typically is most bothersome during and just after athletic activity and resolves after a period of rest. In more severe cases, patients may even have pain with more routine activities such as walking.
There is usually no history of an acute injury, rather most athletes describe a worsening, nagging pain. Unfortunately, this often leads to a delay in diagnosis, and while it usually causes no long-term problems, it does delay the start of treatment.
Diagnosis of a navicular stress fracture is suspected when athletes have pain directly over the navicular bone. There may be a small degree of swelling in the area. Sometimes the navicular stress fracture is seen on X-ray but often requires other tests to be detected. Tests including MRIs, CT scans, and bone scans can all be used to detect this injury.
The usual treatment of a navicular stress fracture is with nonsurgical management.2However, it is critical that treatment is appropriate as these fractures may not heal if not appropriately managed.
Typical treatment consists of rest from activity, limited weight-bearing (crutches) and immobilization in a cast. Duration of treatment depends on a number of factors, but commonly the cast is used for six weeks, followed by a gradual resumption of weight-bearing activities.3
A realistic time frame for a return to athletics, based on a number of research studies, averages about six months.
If athletes try to do too much, too soon, these injuries can take even longer to heal and may not completely heal. Navicular fractures that do not heal (nonunion) may require surgical treatment to better stabilize the injured bone and stimulate a healing response. In some circumstances, athletes may choose to start with surgical treatment, just to ensure that treatment progresses as quickly as possible, and not take the chance of nonsurgical treatment not being effective.