Naturally the foot possesses a pressure distribution system made up of fat lobules: the ball of the foot. Unfortunately, the ball of the foot changes with age and under the stress of excessive use. It can then no longer perform its load-distributing function correctly, which leads to painful metatarsal heads. These pains often also arise in people who wear high heels, because the ball of the foot is not correctly proportioned to support the significant pressures that are shifted onto the forefoot.
When the pressure affects the whole of the forefoot this is known as metatarsalgia, whereas if the pain is localised it is often due to the presence of a callus.