Overview
Morton?s Neuroma is a pathological condition of the common digital nerve in the foot, most frequently between the third and fourth metatarsals (third inter-metatarsal space). The nerve sheath becomes abnormally thickened with fibrous (scar) tissue and the nerve fibres eventually deteriorate.This condition is named for the American surgeon, Thomas George Morton (1835-1903), who first recognised the condition in 1876. Incidentally his father was the dentist who discovered the anaesthetics; initially Nitrous oxide, the very gas used today in cryosurgery for the condition his son lent his name to? Morton?s neuroma.
Causes
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
Morton?s neuroma is a progressive condition which means the symptoms typically get worse over time. Initially people often complain of a tingling or numbness at the base of their toes, typically in the space between the third and fourth toes, or, less commonly , between the second and third toes, which feels a bit like pins and needles. Over time the pain progresses and can feel like a stabbing or burning sensation in the ball of the foot under the toes. Some describe it as feeling as if they are standing on a stone. Normally the pain will get worse when you wear tight fitting shoes. Doing exercise that impacts on the foot such as jogging can also make the symptoms worse. The extent of the pain varies from person to person but in some cases it can be so intense that every step can feel acutely painful.
Diagnosis
The most common condition misdiagnosed as Morton's neuroma is metatarsophalangeal (MTP) joint synovitis. When pain occurs in the third interspace, the clinician may misdiagnose the condition as Morton's neuroma instead of MTP synovitis, which may manifest very much like Morton's neuroma. MTP synovitis is distinguished from Morton's neuroma by subtle swelling around the joint, pain localized mainly within the joint, and pain with forced toe flexion. Palpation of the MTP joint is performed best with a pinching maneuver from the dorsal and plantar aspects of the joint to elicit tenderness of the joint. Other conditions often misdiagnosed as Morton's neuroma include the following. Stress fracture of the neck of the metatarsal. Rheumatoid arthritis and other systemic arthritic conditions. Hammertoe. Metatarsalgia (ie, plantar tenderness over the metatarsal head) Less common conditions that have overlapping symptoms with Morton's neuroma include the following. Neoplasms. Metatarsal head osteonecrosis. Freiburg. steochondrosis. Ganglion cysts. Intermetatarsal bursal fluid collections. True neuromas.
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
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?s Neuroma is a pathological condition of the common digital nerve in the foot, most frequently between the third and fourth metatarsals (third inter-metatarsal space). The nerve sheath becomes abnormally thickened with fibrous (scar) tissue and the nerve fibres eventually deteriorate.This condition is named for the American surgeon, Thomas George Morton (1835-1903), who first recognised the condition in 1876. Incidentally his father was the dentist who discovered the anaesthetics; initially Nitrous oxide, the very gas used today in cryosurgery for the condition his son lent his name to? Morton?s neuroma.
Causes
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
Morton?s neuroma is a progressive condition which means the symptoms typically get worse over time. Initially people often complain of a tingling or numbness at the base of their toes, typically in the space between the third and fourth toes, or, less commonly , between the second and third toes, which feels a bit like pins and needles. Over time the pain progresses and can feel like a stabbing or burning sensation in the ball of the foot under the toes. Some describe it as feeling as if they are standing on a stone. Normally the pain will get worse when you wear tight fitting shoes. Doing exercise that impacts on the foot such as jogging can also make the symptoms worse. The extent of the pain varies from person to person but in some cases it can be so intense that every step can feel acutely painful.
Diagnosis
The most common condition misdiagnosed as Morton's neuroma is metatarsophalangeal (MTP) joint synovitis. When pain occurs in the third interspace, the clinician may misdiagnose the condition as Morton's neuroma instead of MTP synovitis, which may manifest very much like Morton's neuroma. MTP synovitis is distinguished from Morton's neuroma by subtle swelling around the joint, pain localized mainly within the joint, and pain with forced toe flexion. Palpation of the MTP joint is performed best with a pinching maneuver from the dorsal and plantar aspects of the joint to elicit tenderness of the joint. Other conditions often misdiagnosed as Morton's neuroma include the following. Stress fracture of the neck of the metatarsal. Rheumatoid arthritis and other systemic arthritic conditions. Hammertoe. Metatarsalgia (ie, plantar tenderness over the metatarsal head) Less common conditions that have overlapping symptoms with Morton's neuroma include the following. Neoplasms. Metatarsal head osteonecrosis. Freiburg. steochondrosis. Ganglion cysts. Intermetatarsal bursal fluid collections. True neuromas.
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
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.