The sudden pain in the foot may be related to the following causes: 1. It may be caused by tendonitis. This condition is often due to excessive activity of the patient’s foot, or cold, which leads to inflammation of the tendon sheath, and there will be obvious pain as well as abnormal sound and jamming during its activity. 2. There may be flatfoot syndrome. The patient’s arch collapses due to congenital or acquired factors, after which the pain in the ball of the foot suddenly appears when walking long distances. 3. Fatigue fractures may exist. This condition is also seen in patients who walk long distances, where fatigue fractures of the metatarsal bones are caused by excessive activity, followed by sudden onset of pain. 4. It may be caused by lesions of the peripheral nerves. The onset of lumbar disc herniation may stimulate the nerve roots and cause radiating pain in the metatarsal area.