Managing Mortons Neuroma

Overview

Morton’s neuroma is a condition that affects one of the nerves that run between the long bones (metatarsals) in the foot. The exact cause is not certain. Symptoms include pain, burning, numbness and tingling between two of the toes of the foot. About a quarter of people just need simple treatments including modification of their footwear. Sometimes surgery is needed for long-standing (chronic) symptoms.

Causes

Morton’s neuroma develops for several reasons. The primary reason is wearing narrow toe-box shoes, which compress the metatarsal heads. Certain anatomical factors also make nerve compression more likely with the narrow toe box shoes. In some people fibers, the medial and lateral plantar nerves converge close to the heads of the third and fourth metatarsals. This junction creates a larger nerve structure between the metatarsal heads making it more vulnerable to compression.

Symptoms

Symptoms of interdigital neuroma typically manifest as a sharp, burning or tingling sensation in the forefoot. The pain radiates toward the lesser toes and is aggravated by shoe wear. The pain is relieved when the shoe is removed and the forefoot is massaged. Sometimes the symptoms involve specific toes.

Diagnosis

An MRI scan (magnetic resonance imaging) is used to ensure that the compression is not caused by a tumor in the foot. An MRI also determines the size of the neuroma and whether the syndrome should be treated conservatively or aggressively. If surgery is indicated, the podiatrist can determine how much of the nerve must be resected. This is important, because different surgical techniques can be used, depending on the size and the position of the neuroma. Because MRIs are expensive, some insurance companies are reluctant to pay for them. If the podiatrist believes an MRI is necessary, he or she can persuade the insurance company to pay for it by presenting data to support the recommendation.

Non Surgical Treatment

If your Morton’s neuroma is painful, your doctor usually will begin treatment with conservative therapies, including a switch to shoes with low heels, wide toes and good arch support. Padding techniques, including metatarsal pads or toe crest pads. Shoe inserts (orthotics) to help correct any mechanical imbalance in the foot. Anti-inflammatory medication, such as ibuprofen (Advil, Motrin and other brand names) or naproxen (Aleve, Naprosyn and other brand names) A local injection of anesthetic and corticosteroid medication into the affected area. Inflamed or injured nerves can take months to improve, even after the underlying problem has been corrected.Morton neuroma

Surgical Treatment

Patients are commonly offered surgery known as neurectomy, which involves removing the affected piece of nerve tissue. Postoperative scar tissue formation (known as stump neuroma) can occur in approximately 20%-30% of cases, causing a return of neuroma symptoms. Neurectomy can be performed using one of two general methods. Making the incision from the dorsal side (the top of the foot) is the more common method but requires cutting the deep transverse metatarsal ligament that connects the 3rd and 4th metatarsals in order to access the nerve beneath it. This results in exaggerated postoperative splaying of the 3rd and 4th digits (toes) due to the loss of the supporting ligamentous structure. This has aesthetic concerns for some patients and possible though unquantified long-term implications for foot structure and health. Alternatively, making the incision from the ventral side (the sole of the foot) allows more direct access to the affected nerve without cutting other structures. However, this approach requires a greater post-operative recovery time where the patient must avoid weight bearing on the affected foot because the ventral aspect of the foot is more highly enervated and impacted by pressure when standing. It also has an increased risk that scar tissue will form in a location that causes ongoing pain.