Some sources claim that entrapment of the plantar nerve because of compression between the metatarsal heads, as originally proposed by Morton, is highly unlikely, because the plantar nerve is on the plantar side of the transverse metatarsal ligament and thus does not come in contact with the metatarsal heads. It is more likely that the transverse metatarsal ligament is the cause of the entrapment. Despite the name, the condition was first correctly described by a chiropodist named Durlacher, and although it is labeled a "neuroma", many sources do not consider it a true tumor, but rather a perineural fibroma (fibrous tissue formation around nerve tissue).
Although the exact cause for this condition is unclear, a number of factors can contribute to the formation of a neuroma. Biomechanical deformities, such as a high-arched foot or a flat foot, can lead to the formation of a neuroma. These foot types bring on instability around the toe joints, leading to the development of the condition. Trauma can cause damage to the nerve, resulting in inflammation or swelling of the nerve. Improper footwear that causes the toes to be squeezed together is problematic. Avoid high-heeled shoes higher than two inches. Shoes at this height can increase pressure on the forefoot area. Repeated stress, common to many occupations, can create or aggravate a neuroma.
Symptoms include tingling in the space between the third and fourth toes, toe cramping, a sharp, shooting, or burning pain in the ball of the foot and sometimes toes, pain that increases when wearing shoes or pressing on the area, pain that gets worse over time. In rare cases, nerve pain occurs in the space between the second and third toes. This is not a common form of Morton neuroma, but treatment is similar.
Diagnosis of Morton?s Neuroma typically involves a physical examination of the affected foot. Your health care provider will ask you about your symptoms and examine your feet and toes. He will manipulate your toes, pushing them from side to side and squeezing on the spaces in between. This physical exam will allow your health care provider to feel for any lumps that may be present under the soft tissue of your feet. Your health care provider may also listen for any clicking sounds that your bones may be making. Known as Muldor?s Sign, this clicking is common amongst sufferers of foot neuroma. Occasionally, an x-ray or MRI (magnetic resonance imaging) is performed to help rule out any breaks, sprains, or fractures in your foot.
Non Surgical Treatment
Treatment for Morton?s Neuroma usually begins conservatively, with a change in lifestyle choices. People suffering from the condition may find pain relief by reducing activity levels, changing footwear, using orthopedic supports, reducing weight. Medications are also available to help relieve the pain of Morton?s Neuroma. Over-the-counter medications are sometimes very helpful in reducing pain and inflammation. Your health care provider can also provide you with anesthetic or corticosteroid injections. These help to numb the area affected by the neuroma, and reduce inflammation.
If conservative treatments haven't helped, your doctor might suggest injections. Some people are helped by the injection of steroids into the painful area. In some cases, surgeons can relieve the pressure on the nerve by cutting nearby structures, such as the ligament that binds together some of the bones in the front of the foot. Surgical removal of the growth may be necessary if other treatments fail to provide pain relief. Although surgery is usually successful, the procedure can result in permanent numbness in the affected toes.
Ensuring that shoes are well fitted, low-heeled and with a wide toe area may help to prevent Morton's neuroma.