Morton’s neuroma


Also known as Morton’s metatarsalgia, and interdigital neuroma.

A condition that affects the nerves between the base of the toes that supply sensations to this area.

It is usually between the third and fourth toes.

Most commonly affects the third digital nerve of the foot, often leading to neuropathic pain in the affected toes.

The  third interdigital nerve is affected up to 87% of cases, followed by the second in the remainder of the cases.

Morton neuroma occurs bilaterally in 21% of patients.

Characterized by a thickening of the tissue around those nerves and is more common in women than in men.

Characterized by epidural and perineural fibrosis and decrease in myelination, and enlarged nerves compared with autopsy controls.

Caused by long-term pressure, either in the form of injury, irritation, compression on one of the plantar digital nerves.

Repeated stress triggers a response which causes a thickening of the nerve tissue (neuroma).

The second most common compressive neuropathy (carpal tunnel syndrome, the most common close).

Patients typically present between 45 and 54 years of age.

Women, who frequently wear high-heeled or narrow shoes, often suffer from neuroma because these shoes tend to squash, rub, stretch, or compress the nerves between the base of the toes.

High-impact activities such as jogging or running can put increased pressure on the ligaments.

The ratio of patients who undergo surgical excision is 4:1 women greater than men.

Diagnosis is based on clinical history and physical exam.

Patients with certain foot deformities such as bunions, flat feet, and hammer toes, are also more prone these conditions can cause the ligament to put pressure on the nerve as well.

Symptoms are varied: might feel like one is standing on a pebble inside theshoe or even a crumpled or wrinkled a sock, might experience intense pain in the ball of the foot that radiates to the toes, may experience tingling sensation or numbness in the toes or ball of the foot, might feel like there is a protuberance or swelling between the toes, a feeling that the toes are asleep, and the toes might cramp,or experience a clicking sensation when walking.

Patients commonly present with burning pain between the metatarsal heads in the plantar aspect of the foot.

Pain may radiate to the two adjacent toes and patients may report numbness or electrical sensations in the toes.

Tight shoes or high heels may exacerbate symptoms.

Greater than 90% of patients report exacerbation of pain with walking and 86% report worsening of pain with tight shoes, 81% have pain relief by rest, and 79% report pain on stretching the toes.

Physical examination typically shows tendon is some compression of the effected webspace.

Imaging is usually not necessary to make the diagnosis, but standing foot radiographic imaging may evaluate other conditions, and ultrasound can identify hypoechoic mass in the metatarsal heads or MRI imaging may be performed.

Ultrasound, and MRI sensitivity are greater than 90% for diagnosis.

It will not go away on its own.

One of the most important measures to help alleviate foot pain is wearing proper footwear.

Shoes should have good arch support and a broad toe box that allows the toes to spread out.

Treatment measures include:

maintaining an appropriate body weight

avoiding activities which put pressure on the foot

massaging the foot and affected toes resting the foot

using an icepack on the affected area

Exercises can improve strength and flexibility of the arch.

Beneficial exercises include stretching the Achilles muscle, the calf, the lower leg and the plantar fascia along the bottom of the foot, as well as exercises in general that strengthen foot muscles.

Orthotics and metatarsal or neuroma pads

Injections can be either corticosteroid injections or alcohol sclerosing injections may be beneficial: first reduces inflammation and pain, and the latter can help reduce the neuroma and provide some pain relief.

Adverse effects with corticosteroid injections includes skin bleaching, and skin atrophy.

As a last resort, consider surgery.

Surgery can result in permanent numbness of the affected toes.

Operative treatment typically consists of excising the common interdigital nerve with more than 95% pain reduction.

Perineural fibrosis producing symptomatic entrapment neuropathy of the interdigital nerve at the distal extent of the transverse ligament.

Higher prevalence in women, mean age at onset in the fifth decade, most common location in the third intermetatarsal space with exacerbation of symptoms with constricting shoe wear.

Characterized by pain and numbness relieved by removing footwear.

Patients typically have pain on weight bearing, with pain shooting into contiguous halves of two toes.

Patients may experience burning, numbness and paresthesias.

Usually the third digital space between the 3rd and 4th toes is affected, with occasional involvement is the 2nd and 3rd interdigital space.

Pain related to pressure on the enlarged section of nerve where it passes between the metatarsal heads, and squeezed between them.

The first toe is usually not involved.

Involvement in the 4th/5th interdigital space is extremely rare.

Not associated with erythema, inflammatory changes limited movement or deformities of the foot.

Pressure between metatarsal heads replicates the symptoms.

MRI may be helpful in diagnosis, but may be inconclusive.

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