Mortons neuroma  is a benign neuroma of an intermetatarsal plantar nerve, most commonly of the second and third intermetatarsal spaces (between the second/third and third/fourth metatarsal heads; the first is of the big toe), which results in the entrapment of the affected nerve. The main symptoms are pain and/or numbness, sometimes relieved by ceasing to wear footwear with tight toe boxes and high heels (which have been linked to the condition). The condition is named after Thomas George Morton, though it was first correctly described by a chiropodist named Durlacher.Some sources claim that entrapment of the plantar nerve resulting from 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 into contact with the metatarsal heads. It is more likely that the transverse metatarsal ligament is the cause of the entrapment.Though the condition is labeled as a neuroma, many sources do not consider it a true tumor, but rather a perineural fibroma (fibrous tissue formation around nerve tissue). Signs and symptoms
Symptoms include pain on weight bearing, frequently after only a short time. The nature of the pain varies widely among individuals. Some people experience shooting pain affecting the contiguous halves of two toes. Others describe a feeling akin to having a pebble in the shoe or walking on razor blades. Burning, numbness, and paresthesia may also be experienced.
Footwear and orthotics are most effective in neuromas that have existed less than four and a half months and are smaller than 4–5 millimetres (0.16–0.20 in). To prevent or treat Mortons neuroma, comfortable shoes that are sufficiently long and have a wide toe box, flat heel, and thick sole are recommended.Corticosteroid injections can relieve inflammation in some patients and help end the symptoms. For some patients, however, the inflammation and pain recur after some weeks or months, and corticosteroids may only be used a limited number of times because they cause progressive degeneration of ligamentous and tendinous tissues. About 30% of people who receive steroid injections go on to have surgery. According to a 2021 review, it is most effective in neuromas smaller than 6.3 millimetres (0.25 in).Sclerosing alcohol injections are an increasingly available treatment alternative if other management approaches fail. Dilute alcohol (4%) is injected directly into the area of the neuroma, causing toxicity to the fibrous nerve tissue. Frequently, treatment must be performed two to four times, with one to three weeks between interventions. A 60–80% success rate has been achieved in clinical studies, equal to or exceeding the success rate for surgical neurectomy, with fewer risks and less significant recovery. If done with more concentrated alcohol under ultrasound guidance, the success rate is considerably higher and fewer repeat procedures are needed.Radiofrequency ablation is also used in the treatment of Mortons neuroma.