The navicular is part of the tarsals of the foot and is located on the inside part of the foot. When a stress fracture occurs, a small crack in the bone appears due to overloading, in example when training excessively. 90% of all stress fracture occur in the lower limb (Robertson and Wood, 2017).
This can result from an imbalance between bone formation and bone resorption. When the navicular is loaded (running /jumping), it responds by increasing bone turnover. If new bone formation cannot keep up with bone resorption, areas of weakness can develop within the navicular and can develop into a stress fracture if the bone is continually loaded.
Management of this condition should include analysis of training principles, footwear and biomechanics of the lower limb. Female athletes can be more prone to stress fractures due to changes in diet and change in menstrual cycle.
Robertson G.A.J. and Wood A. M., 2017, Lower limb stress fractures in sport: Optimising their management and outcome, World Journal of Orthopedics, 8(3); pp: 242-255