Morton's neuroma is named after Dr Morton who first described this condition in 1876. It is sometimes called Morton's metatarsalgia or interdigital neuroma. It is a condition that affects one of the common plantar digital nerves that run between the long bones (metatarsals) in the foot. It most commonly affects the nerve between the third and fourth metatarsal bones, causing pain and numbness in the third and fourth toes. It can also affect the nerve between the second and third metatarsal bones, causing symptoms in the second and third toes. Morton's neuroma rarely affects the nerve between the first and second, or between the fourth and fifth, metatarsal bones. It tends to affect only one foot. It is rare to get two neuromas at the same time in the same foot.
When a nerve is pinched between bones, the result is swelling of the nerve. It is this swelling which is referred to as a Neuroma. When the condition occurs in the foot, it is known as a Morton?s Neuroma. Morton?s Neuroma is technically not a tumor. Rather, it is a thickening of the tissue that surrounds the digital nerves leading to the toes. These nerves allow for physical sensation on the skin of the toes. The region of inflammation is found where the digital nerve passes under the ligament connecting the toe bones (metatarsals) in the forefoot. Morton?s Neuroma commonly develops between the third and fourth toes, generally as a result of ongoing irritation, trauma or excessive pressure. In some cases, the second and third toes are involved. Morton?s Neuroma is confined to one foot in most cases, though it can occur in both, particularly in athletes such as runners.
The most common symptom of Morton's neuroma is localized pain in the interspace between the third and fourth toes. It can be sharp or dull, and is worsened by wearing shoes and by walking. Pain usually is less severe when the foot is not bearing weight.
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
The first line of treatment is to try modifying footwear. Often simply wearing broader fitting shoes can reduce pressure on the neuroma and so reduce pain. Orthotic inserts can also help as they can again help reduce pressure on certain parts of the foot. Padding and taping the toe area is another option. In some cases a steroid injection into the foot may be suggested. This can be done as a day case without the need for anaesthesia and helps reduce inflation of the nerve. It can halt the pain in round 70 % of cases. Sometimes a combination of alcohol and local anaesthesia may be injected as this helps reduce pain.
When medications or other treatments do not work, podiatric surgery may be required. The most common surgical procedure for treating Morton?s neuroma is a neurectomy, in which part of the nerve tissue is removed. Although this procedure effectively removes the original neuroma, sometimes scar tissue known as a stump neuroma forms at the site of the incision. This may result in tingling, numbness, or pain following surgery. Surgery is effective in relieving or reducing symptoms for Morton?s neuroma patients in about 75% to 85% of all cases. Occasionally, minimally invasive radio frequency ablation is also used to treat Morton's neuroma.