Overview
Morton's neuroma is an enlarged nerve that usually occurs in the third interspace, which is between the third and fourth toes. To understand Morton's neuroma further, it may be helpful to look at the anatomy of the foot. Problems often develop in the third interspace because part of the lateral plantar nerve combines with part of the medial plantar nerve here. When the two nerves combine, they are typically larger in diameter than those going to the other toes. Also, the nerve lies in subcutaneous tissue, just above the fat pad of the foot, close to an artery and vein. Above the nerve is a structure called the deep transverse metatarsal ligament. This ligament is very strong, holds the metatarsal bones together, and creates the ceiling of the nerve compartment. With each step, the ground pushes up on the enlarged nerve and the deep transverse metatarsal ligament pushes down. This causes compression in a confined space.
Causes
Morton's Neuroma is a foot condition caused from an abnormal function of the foot that leads to bones squeezing a nerve usually between the 3rd and 4th metatarsal heads. Symptoms of Morton's Neuroma often occur during or after you have been placing significant pressure on the forefoot area, while walking, standing, jumping, or sprinting. This condition can also be caused by footwear selection. Footwear with pointed toes and/or high heels can often lead to a neuroma. Constricting shoes can pinch the nerve between the toes, causing discomfort and extreme pain.
Symptoms
It usually occurs in between the 3rd and 4th toes (about 65% of cases) as is pictured to the right. It is less commonly found in the 2nd webspace, and rarely at all in the 1st or 4th webspaces. You can also experience pins and needles and/or numbness as a result of the nerve being affected. The condition tends to occur predominantly in middle aged females.
Diagnosis
The diagnosis of a Morton's neuroma can usually be made by the doctor when the history of pain suggests it and the examination elicits the symptoms. The foot is generally tender when the involved area is compressed and symptoms of pain and sometimes tingling can be elicited when the sides of the foot are squeezed. Magnetic resonance imaging (MRI) or ultrasound testing can be used to confirm the diagnosis if necessary.
Non Surgical Treatment
Most non-operative treatment is usually successful, although it can take a while to figure out what combination of non-operative treatment works best for each individual patient. Non-operative treatment may include the use of comfort shoe wear. The use of a metatarsal pad to decrease the load through the involved area of the plantar forefoot. A period of activity modification to decrease or eliminate activities, which may be exacerbating the patient?s symptoms. For example, avoiding long periods of standing or other activities that result in significant repetitive loading to the forefoot can be very helpful. Wearing high heels should be avoided. Local can help decrease inflammation associated with the nerve. However, this does not necessarily address the underlying loading forces that maybe causing the injury to the nerve in the first place. It has been proposed that an alcohol injection in and around the nerve will cause a controlled death to the nerve and subsequently eliminate symptoms. In theory, this may be helpful. In practice, adequate prospective studies have not demonstrated the benefit of this procedure above and beyond the other standard, non-operative treatments available. In addition there is the concern that the alcohol will cause excessive scarring and damage to other important structures in the area.
Surgical Treatment
Interdigital neurectomy (removal of the diseased nerve) in right hands, should give satisfactory results almost all the time. Some of the reasons behind failure is when not enough nerve is dissected, mistakes in initial diagnosis, or bad handling of adjacent nerves, tendons and joint capsules during the operation. It is very common and acceptable to have some numbness in the area where the nerve used to be. This never causes any discomfort and often gets better in few years. It is crucial to address the biomechanical pathologies underlying the impingement of the nerve during and after the surgery.
Prevention
Wearing proper footwear that minimizes compression of the forefoot can help to prevent the development of and aggravation of a Morton's neuroma.
Morton's neuroma is an enlarged nerve that usually occurs in the third interspace, which is between the third and fourth toes. To understand Morton's neuroma further, it may be helpful to look at the anatomy of the foot. Problems often develop in the third interspace because part of the lateral plantar nerve combines with part of the medial plantar nerve here. When the two nerves combine, they are typically larger in diameter than those going to the other toes. Also, the nerve lies in subcutaneous tissue, just above the fat pad of the foot, close to an artery and vein. Above the nerve is a structure called the deep transverse metatarsal ligament. This ligament is very strong, holds the metatarsal bones together, and creates the ceiling of the nerve compartment. With each step, the ground pushes up on the enlarged nerve and the deep transverse metatarsal ligament pushes down. This causes compression in a confined space.
Causes
Morton's Neuroma is a foot condition caused from an abnormal function of the foot that leads to bones squeezing a nerve usually between the 3rd and 4th metatarsal heads. Symptoms of Morton's Neuroma often occur during or after you have been placing significant pressure on the forefoot area, while walking, standing, jumping, or sprinting. This condition can also be caused by footwear selection. Footwear with pointed toes and/or high heels can often lead to a neuroma. Constricting shoes can pinch the nerve between the toes, causing discomfort and extreme pain.
Symptoms
It usually occurs in between the 3rd and 4th toes (about 65% of cases) as is pictured to the right. It is less commonly found in the 2nd webspace, and rarely at all in the 1st or 4th webspaces. You can also experience pins and needles and/or numbness as a result of the nerve being affected. The condition tends to occur predominantly in middle aged females.
Diagnosis
The diagnosis of a Morton's neuroma can usually be made by the doctor when the history of pain suggests it and the examination elicits the symptoms. The foot is generally tender when the involved area is compressed and symptoms of pain and sometimes tingling can be elicited when the sides of the foot are squeezed. Magnetic resonance imaging (MRI) or ultrasound testing can be used to confirm the diagnosis if necessary.
Non Surgical Treatment
Most non-operative treatment is usually successful, although it can take a while to figure out what combination of non-operative treatment works best for each individual patient. Non-operative treatment may include the use of comfort shoe wear. The use of a metatarsal pad to decrease the load through the involved area of the plantar forefoot. A period of activity modification to decrease or eliminate activities, which may be exacerbating the patient?s symptoms. For example, avoiding long periods of standing or other activities that result in significant repetitive loading to the forefoot can be very helpful. Wearing high heels should be avoided. Local can help decrease inflammation associated with the nerve. However, this does not necessarily address the underlying loading forces that maybe causing the injury to the nerve in the first place. It has been proposed that an alcohol injection in and around the nerve will cause a controlled death to the nerve and subsequently eliminate symptoms. In theory, this may be helpful. In practice, adequate prospective studies have not demonstrated the benefit of this procedure above and beyond the other standard, non-operative treatments available. In addition there is the concern that the alcohol will cause excessive scarring and damage to other important structures in the area.
Surgical Treatment
Interdigital neurectomy (removal of the diseased nerve) in right hands, should give satisfactory results almost all the time. Some of the reasons behind failure is when not enough nerve is dissected, mistakes in initial diagnosis, or bad handling of adjacent nerves, tendons and joint capsules during the operation. It is very common and acceptable to have some numbness in the area where the nerve used to be. This never causes any discomfort and often gets better in few years. It is crucial to address the biomechanical pathologies underlying the impingement of the nerve during and after the surgery.
Prevention
Wearing proper footwear that minimizes compression of the forefoot can help to prevent the development of and aggravation of a Morton's neuroma.