Foot fracture, Kohler's disease and neuritis. Artwork showing causes of foot pain. The third metatarsal bone of the middle toe has a stress fracture. Stress fractures are caused by repeated jarring of a bone, and commonly occur in the metatarsal bones. The second metatarsal bone (at right of fracture) exhibits Kohler's disease. This condition involves degenerative changes possibly due to disruption of the blood supply. The bone becomes soft and may be deformed or flattened by surrounding pressure. The lateral plantar nerve, which serves the fourth and fifth toes, is inflamed (purple area) with neuritis. This can be caused by infection or injury to the foot.