Metatarsalgia refers to pain in the balls of the feet (the area between the toes and the arch). The most important structures in the balls of the feet are the five metatarsal heads (the ends of the metatarsal bones that connect to the toes) and the protective fatty pad that cushions the ball of the foot.
Each time we take a step forward, we push-off with our toes and the ball of the foot, forcing ourselves forward. To do this, we force 100% of our body weight on these structures.
If they are not aligned correctly, or if we have insufficient fatty padding, we experience pain in the ball of the foot.
CAUSES:
As we step down on the ball of the foot, the metatarsal arch begins to flatten in response to our body weight. This allows the ball of the foot and their fat pad to function as a shock absorber for the underlying bones, joints, and soft tissue structures. As we age, the fatty protective pad begins to thin.
When the pad is not of optimum thickness, the force and weight of each step taken is passed on to the underlying structures, rather than absorbed and whisked away by the fat pad.
Excessive and prolonged pressure on the ball of the foot will cause the fat pad to be thinned or destroyed. This eventually produces inflammation and pain in the soft tissues, bones, and joints in the ball of the foot.
Lack of normal fatty pad under the metatarsal heads will apply abnormal pressure on the underlying skin. The skin may respond to this increased pressure by building up a painful callus.
Two major causes are high heel shoes and walking in shoes with very thin soles.