While many things can cause pain to the side bone of the foot, one of the most common causes are stress fractures that occur with a small break in a foot bone, according to Foot-Pain-Explored.com. These breaks usually occur when engaging in repetitive sports activities.
Stress fractures can cause minimal-to-severe pain in any given location of the foot, depending on the affected area, and the pain typically increases if not treated, states Foot-Pain-Explored.com. Cuboid syndrome is another common cause of foot pain and occurs when the cuboid bone, located in the side of the foot, becomes dislocated. Generally caused by a previous injury, cuboid syndrome is difficult to diagnose and affects 7 percent of people who have previously sprained their ankles.
Additional causes of foot bone pain may be peroneal tendonitis, which is repetitive and painful tension in the tendon near the heel, and tarsal coalition, which is caused by two or more bones being connected to one another, explains Foot-Pain-Explored.com. Bunions, corns and calluses can also cause mild-to-severe pain in the side of the foot. Rheumatoid or degenerative arthritis are less common causes of bone pain in the feet, with symptoms that wax and wane, but are nonetheless difficult to treat.