There are many reasons why patient developed pain in the ball of the foot. In my experience with over a decade practicing it can be summarized in 3 categories: systemic conditions, trauma and abnormal biomechanics.
Every step in a perfect foot increases stress from the heel to the tip of the toe; however when patient have flatfeet or high arches these will increased stress to the ball. Let us look at patients with high arch feet first. When weight-bearing there is a greater percentage of pain on the ball of foot and the heel. The arch does not come in contact with the ground very much. Therefore we see more conditions related to stress fractures bursitis and capsulitis with this foot structure.
Individuals however that have flat feet
have a tendency to develop forefoot splaying which creates more pressure in her shoes developing bunions, tendonitis and eventually neuromas. Further patient that have bunion deformities are also at risk of developing forefoot pain and simple correction of a bunion will resolve the forefoot pain. Below is a inflamed Morton neuroma that was removed.
When looking at systemic factors of why patient developed forefoot pain conditions like rheumatoid arthritis, psoriatic arthritis, and diabetes are just some that are at risk of developing soft tissue masses ( nodules and fat atrophy ).
Diabetics eventually get corns and calluses and potential foreign bodies due to neuropathy causing pain and ulcerations at times.
Final factor of why forefoot pain develops is through trauma. It is seen very commonly in sports activities like running, soccer basketball in any sport that requires strain and high pressure load. As a younger goalie I developed many metatarsal stress fracture from high speed pucks and overload.