Morton's Neuroma
A neuroma is the thickening of the tissue around one of your nerves leading to your toe. I can cause a sharp, burning pain in the ball of the foot and extends to your toes, tingling and numbness, and/or the feeling of standing on a pebble or small rock.
Application
The most common applications for Morton's Neuroma.
A Morton's neuroma is a benign (noncancerous) swelling along a nerve in the foot that carries sensations from the toes. The reason the nerve starts to swell is unknown. But once swelling begins, the nearby bones and ligaments put pressure on the nerve, causing more irritation and inflammation. This produces burning pain, numbness, tingling and other abnormal sensations in the toes. A Morton's neuroma also is called an interdigital neuroma, intermetatarsal neuroma or a forefoot neuroma.
A Morton's neuroma usually develops between the third and fourth toes. Less commonly, it develops between the second and third toes. Other locations are rare. It also is rare for a Morton's neuroma to develop in both feet at the same time. The condition is much more common in women than men, probably as a result of wearing high-heeled, narrow-toed shoes. This style of shoe tends to shift the bones of the feet into an abnormal position, which increases the risk that a neuroma will form. Being overweight also increases the risk of a Morton's neuroma.
Clinical Presentation
- Normally, there are no outward signs, such as a lump, because this is not really a tumor.
- Burning pain in the ball of the foot that may radiate into the toes. The pain generally intensifies with activity or wearing shoes. Night pain is rare.
- There may also be numbness in the toes, or an unpleasant feeling in the toes.
- A palpable “click” or Mulders sign may be elicited.
Treatment
NON-SURGICAL TREATMENT
Initial therapies are nonsurgical and relatively simple. They can involve one or more of the following treatments:
- Changes in footwear. Avoid high heels or tight shoes, and wear wider shoes with lower heels and a soft sole. This enables the bones to spread out and may reduce pressure on the nerve, giving it time to heal.
- OTC or Custom shoe inserts and pads also help relieve irritation by lifting and separating the bones, reducing the pressure on the nerve.
- One or more injections of a corticosteroid medication can reduce the swelling and inflammation of the nerve, bringing some relief.
- Sclerosing injections with 4% dilute dehydrated alcohol can be utilized to create a chemical neurolysis to reduce pain.
SURGICAL TREATMENT
Excision of the affected portion of the nerve is perhaps the most common approach to neuroma surgery. Excision requires identifying the common digital portion of the nerve and following the structure to the proper digital branches. Care must be taken to avoid other structures in the area. Various surgical approaches have been used, the most common of which is a dorsal incision over the involved intermetatarsal space. Plantar incisional approaches are most often used in revisionary procedures, although they also have been described as an initial surgical approach. Excision may also be elected when prior decompression surgery has failed to resolve symptoms.
Decompression of the intermetatarsal nerve through the use of endoscopic and minimally invasive techniques has been reported in recent years. Open decompression of the nerve by releasing the deep transverse intermetatarsal ligament and performing an external neurolysis has been described. In addition, transposition with nerve release has been shown to be useful.
Cryogenic neuroablation is a minimally invasive procedure that applies a temperature of -50°C to -70°C to the nerve. This results in degeneration of the axons and myelin, while leaving the epineurium and perineurium intact. Preserving these structures helps prevent stump neuromas during nerve regeneration; this is the greatest advantage of cryogenic ablation. However, there are limitations of this procedure. The results are not permanent, and it is not as effective on larger neuromas or in the presence of thick fibrosis. Several investigators have advocated this technique.
Injury Prevention
Wearing high-heeled shoes or shoes that are tight or ill fitting can place extra pressure on the toes and ball of the foot.
Participating in high-impact athletic activities such as jogging or running may subject the patient's feet to repetitive trauma. Sports that feature tight shoes, such as snow skiing or rock climbing, can put pressure on the patient's toes.
- People who have other foot deformities such as bunions, hammertoes, high arches or flatfeet are at higher risk of developing Morton's neuroma.
Billing Codes
Recommended prescription and product billing codes.
- Initial evaluation and diagnosis
- Diagnostic:
- X-ray
- Diagnostic Ultrasound
- Injection Therapy: Cortico-steroid
- Sclerosing
- OTC Orthotics
- Custom Orthotics
FOLLOW UP
- Asses effectiveness of initial therapy
- If patient improving continue plan
- If not improving:
- Consider surgery: excision or decompression
- Consider changing injectable
