Mortons Neuroma
Morton's Neuroma is a painful condition of the forefoot that is caused by the entrapment of the common intermetatarsal nerve as it passes through the forefoot to the toes. This condition was first described by Dr. Morton, a Viennese physician, in 1876. The most common location for Morton's neuroma is between the third and fourth toes. The second most common location is between the second and third toes.
Causes
Clinicians and surgeons recognize a number of factors that may aggravate Morton's neuroma, but the primary cause of Morton's neuroma remains elusive. Shoes that are tight in the forefoot will contribute to the symptoms of Morton's Neuroma by binding the forefoot and compressing the common intermetatarsal nerve. High heels will also act to increase the ground reactive forces. Ground reactive force is the amount of force generated as the foot pushes against a fixed surface like the floor. With high heels, the amount and focus of ground reactive force increases since weight bearing is focused in a smaller area (just the forefoot). A higher heel also puts the common intermetatarsal nerve under tension, making it more prone to injury. Activities such as squatting will increase the ground reactive force applied to the plantar foot and aggravate the symptoms of Morton's neuroma. And finally, clinician also agree that hypermobility of the forefoot can contribute to the formation of Morton's neuroma.