Pain under the ball of the foot often gets labelled as metatarsalgia which is a pretty meaningless term. It is like saying that the diagnosis is knee pain. It could mean anything and the actual diagnosis could be any one of multiple reasons. The term ‘sore knee’ is not a diagnosis and neither is the term ‘metatarsalgia’. Pain in the ball of the foot could be anything from a pinched nerve, to a callus to a strained ligament. The most common reason for metatarsalgia is a plantar plate tear. The plantar plate is a string ligament under the joints in the ball of the foot. This ligament plays an important role in the stability of these joints. The exact cause of the problem is not clear but there are a number of known risk factors such as bunions and being overweight. The pain of a plantar plate tear is typically pain under the joint on walking and on palpation just past the end of the joint. The pain will get worse with increased activity levels. An ultrasound is often used to help make the diagnosis.
The management of a plantar plate tear is to reduce activity levels to reduce the stress on the area. Strapping can be used to hold the toe downwards or plantarflexed and metatarsal pads can also be used to achieve the same thing. A rocker sole shoe all decreases the demands on the joint and can also be used along with the strapping and the metatarsal pad. This generally helps most cases of a plantar plate tear, but it can take quite a while, mostly as we still have to walk on the foot so there is still some stress on the ligament. In those cases where these conservative measures do not help, surgery is often indicated. The tear in the ligament is surgically repaired.