Stress fracture is a tiny crack in the bone or severe bruising within a bone. Stress fractures are caused by repetitive activity or from overuse.
They commonly occur when people change their activities – such as by trying a new exercise, suddenly increasing the intensity of their workouts, or changing the workout surface (jogging on a treadmill vs. jogging outdoors). In addition, if osteoporosis or other disease has weakened the bones, just doing everyday activities may result in a stress fracture.
The weight-bearing bones of the foot and lower leg are more prone to stress fractures because of the repetitive forces they must absorb during activities like walking, running, and jumping.
Stress fractures occur most often in the second and third metatarsals in the foot, which are thinner (and often longer) than the adjacent first metatarsal. This is the area of greatest impact on your foot as you push off when you walk or run.
Stress fractures are also common in the calcaneus (heel); fibula (the outer bone of the lower leg); talus (ankle bone); and the navicular (the bone on the top of the midfoot).
Refraining from high impact activities for an adequate period of time is the key to recovering from a stress fracture in the foot or ankle. Returning to activity too quickly can not only delay the healing process but also increase the risk for a complete fracture. Should a complete fracture occur, it will take far longer to recover and return to activities.