Mortons Neuralgia

Definition

This can generally be described as an irritation and/or swelling of the sensory nerve that branches near the heads of the metatarsal bones. Each time, a nerve branch goes to the outside of the innermost toe, and the inside of the most exterior toe.

Such neuroma is most common at the height of the third intermetatarsal web space (this is the space between two metatarsal bones) and to a lesser extent at the level of the second web space. It is mainly seen in women, not necessarily on both feet.

Symptoms
Usually people complain of a kind of electrical discharge or a shooting pain between two toes. However, this pain is almost exclusively observed while wearing shoes, during walking, or while standing upright for a long time in the same place.
Especially when wearing tight shoes, one should stop walking, remove the shoes and move the toes a little bit, and perhaps put the foot on a cold surface. Some patients have a radiating pain in the back of the metatarsal. Also tingling in the toes, which are innervated by the concerned nerve, can be experienced.

Causes
Since the irritation of the nerve leads to inflammation and/or swelling, one has to deal with the causes during the treatment. This irritation can be due to external mechanical factors such as bursitis, metatarsal arthritis, necrosis or swelling, metatarsalgia by mechanical overpressure. It is the reason why, Moton’ neuroma is frequently associated  with hallux valgus, shortened Achilles tendon.Sometimes, the formation of a neuroma is less clear.

After a clinical suspicion, one must always request a simple standing radiograph and an ultrasound. If there is still doubt after that, an MRI can confirm the diagnosis.


Medical treatment

First line, the treatment is medical. Wearing shoes with a wide tip and a heel not higher than 4 cm, if necessary together with wearing orthotics with a retro capitale support, should be considered as initial treatment. The injection of some cortisone, to be repeated several times, is another possibility. Achilles tendon stretching is associated, too.


Surgical treatment

The neuroma can be released from its fibrous area.

The neuroma can be  removed, chemically (alcholization) or surgically,  which postoperatively can lead to a hollow feeling in the region that was previously innervated by that nerve. Another rare consequence of removing that sensory nerve is the development of a new neuroma, which sometimes makes the preoperative symptoms recur.

Associated lesions , as hallux valgus, metatarsalgia can be treated during the same procedure.


Post-operative care

Immediate weight-bearing with post-operative shoes is proposed , with return to work  after 3 weeks and sporting activities at 1 month, depending on associated bone procedures obviously