Overview
Morton neuroma (interdigital neuroma), first described in 1876, is a perineural fibrosis and nerve degeneration of the common digital nerve. Morton neuroma, or Morton's neuroma, is not a true neuroma, although it results in neuropathic pain in the distribution of the interdigital nerve secondary to repetitive irritation of the nerve. The most frequent location is between the third and fourth metatarsals (third webspace). Other, less common locations are between the second and third metatarsals (second webspace) and, rarely, between the first and second (first webspace) or fourth and fifth (fourth webspace) metatarsals.
Causes
A Morton's Neuroma is not a true neuroma, which is a tumor that is generally benign. Rather, it is an enlargement of the nerve where it goes between the metatarsal bones of the foot. Because the nerve no longer fits between the gap, the pressure causes pain and sometimes numbness. This enlargement of the nerve is often an inflammation due to irritation. If the forefoot becomes compressed due to shoes that are too narrow, the nerve becomes damaged and inflamed. This inflammation means the nerve no longer fits in the space between the bones, creating further irritation and more inflammation. If this vicious circle can be broken, the problem may be resolved. However, in some situations the nerve can have fibrous tissues formed around it, which may require the destruction of the nerve or surgical removal.
Symptoms
While the condition may at first only appear during heavy repetitive stress or when wearing particular shoes which aggravate the foot, the Neuroma can become increasingly inflamed and produce more constant discomfort, lasting days or weeks. Runners may experience pain pushing off from starting blocks. Tight or narrow shoes as well as high heels likewise aggravate the Neuroma. A checklist of symptoms includes burning pain, occasionally numbness in the ball of the foot. Radiating pain from the ball of the foot to the toes. Intensifying pain during activity and when wearing shoes. Occasional numbness, discomfort, tingling or ?electrical shock sensation? in the toes. Pain between the third and fourth toes, often occurring from the outer side of one toe to the inner side of the adjoining toe. Pain upon leaving the starting blocks in running sports.
Diagnosis
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
If symptoms are severe or persistent and self-help measures did not help, the doctor may recommend corticosteroid injections, a steroid medication that reduces inflammation and pain is injected into the area of the neuroma. Only a limited number of injections are advised, otherwise the risk of undesirable side effects increases, including hypertension (high blood pressure) and weight gain. Alcohol sclerosing injections, studies have shown that alcohol injections reduce the size of Morton's neuromas as well as alleviating pain. This is a fairly new therapy and may not be available everywhere. The doctor injects alcohol in the area of the neuroma to help sclerose (harden) the nerve and relieve pain. Injections are typically administered every 7 to 10 days. For maximum relief 4 to 7 injections are usually needed.
Surgical Treatment
Recently, an increasing number of procedures are being performed at specialist centers under radiological or ultrasound guidance. Recent studies have shown excellent results for the treatment of Morton's neuroma with ultrasound guided steroid injections, ultrasound guided sclerosing alcohol injections, ultrasound guided radiofrequency ablation and ultrasound guided cryo-ablation.
Morton neuroma (interdigital neuroma), first described in 1876, is a perineural fibrosis and nerve degeneration of the common digital nerve. Morton neuroma, or Morton's neuroma, is not a true neuroma, although it results in neuropathic pain in the distribution of the interdigital nerve secondary to repetitive irritation of the nerve. The most frequent location is between the third and fourth metatarsals (third webspace). Other, less common locations are between the second and third metatarsals (second webspace) and, rarely, between the first and second (first webspace) or fourth and fifth (fourth webspace) metatarsals.
Causes
A Morton's Neuroma is not a true neuroma, which is a tumor that is generally benign. Rather, it is an enlargement of the nerve where it goes between the metatarsal bones of the foot. Because the nerve no longer fits between the gap, the pressure causes pain and sometimes numbness. This enlargement of the nerve is often an inflammation due to irritation. If the forefoot becomes compressed due to shoes that are too narrow, the nerve becomes damaged and inflamed. This inflammation means the nerve no longer fits in the space between the bones, creating further irritation and more inflammation. If this vicious circle can be broken, the problem may be resolved. However, in some situations the nerve can have fibrous tissues formed around it, which may require the destruction of the nerve or surgical removal.
Symptoms
While the condition may at first only appear during heavy repetitive stress or when wearing particular shoes which aggravate the foot, the Neuroma can become increasingly inflamed and produce more constant discomfort, lasting days or weeks. Runners may experience pain pushing off from starting blocks. Tight or narrow shoes as well as high heels likewise aggravate the Neuroma. A checklist of symptoms includes burning pain, occasionally numbness in the ball of the foot. Radiating pain from the ball of the foot to the toes. Intensifying pain during activity and when wearing shoes. Occasional numbness, discomfort, tingling or ?electrical shock sensation? in the toes. Pain between the third and fourth toes, often occurring from the outer side of one toe to the inner side of the adjoining toe. Pain upon leaving the starting blocks in running sports.
Diagnosis
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
If symptoms are severe or persistent and self-help measures did not help, the doctor may recommend corticosteroid injections, a steroid medication that reduces inflammation and pain is injected into the area of the neuroma. Only a limited number of injections are advised, otherwise the risk of undesirable side effects increases, including hypertension (high blood pressure) and weight gain. Alcohol sclerosing injections, studies have shown that alcohol injections reduce the size of Morton's neuromas as well as alleviating pain. This is a fairly new therapy and may not be available everywhere. The doctor injects alcohol in the area of the neuroma to help sclerose (harden) the nerve and relieve pain. Injections are typically administered every 7 to 10 days. For maximum relief 4 to 7 injections are usually needed.
Surgical Treatment
Recently, an increasing number of procedures are being performed at specialist centers under radiological or ultrasound guidance. Recent studies have shown excellent results for the treatment of Morton's neuroma with ultrasound guided steroid injections, ultrasound guided sclerosing alcohol injections, ultrasound guided radiofrequency ablation and ultrasound guided cryo-ablation.