Morton's metatarsalgia is a condition associated with a painful neuroma* on the digital nerve causing pain in the foot. Charcterised by perineural fibrosis and nerve degeneration due to repetitive irritation, is thought to be due to irritation of the digital nerve caused by repeated trauma, ischemia or entrapment of the nerve, occurs most frequently in women aged 40-50 who wear high-heeled, pointed-toe shoes. The neuroma occurs at the level of the metatarsal necks. The common digital nerve to the third/fourth metatarsal spaces is most often affected, although other interspaces can be involved.
The pain of Morton's neuroma occurs when the nerve connecting the toe bones (metatarsal bones) becomes irritated or compressed. The exact cause of the irritation is unknown, but it may be the metatarsal bones pressing against the nerve when the gap between the bones is narrow. This causes the nerve and surrounding tissue to thicken. Some experts believe that a number of other foot problems, including flat feet, high foot arches, bunions and hammer toes, may also play a role in Morton's neuroma.
Symptoms associated with a neuroma include a dull burning sensation radiating towards the toes, a cramping feeling, or even a stinging, tingling sensation that can be described as being similar to an electric shock. It is often worse when wearing shoes with most people finding the pain disappears when removing their shoes.
Morton?s neuroma can be identified during a physical exam, after pressing on the bottom of the foot. This maneuver usually reproduces the patient?s pain. MRI and ultrasound are imaging studiesthat can demonstrate the presence of the neuroma. An x-ray may also be ordered to make sure no other issues exist in the foot. A local anesthetic injection along the neuroma may temporarily abolish the pain, and help confirm the diagnosis.
Non Surgical Treatment
Once a diagnosis is obtained, it is essential to begin treatment immediately. Your podiatric physician will advise you on the most effective means. If caught early enough, good foot care, shoes that fit properly, and/or orthoses may eliminate the need for any further intervention. Other conservative measures might include oral non-steroidal anti-inflammatory medication (NSAIDS), physical therapy, ultrasound or other non-invasive measures. If that doesn?t work, your podiatric physician might use injectable steroids, and/or a local anesthetic around the neuroma to reduce inflammation and pain. Many patients report relief after these measures are taken.
Majority of publications including peer review journal articles, surgical technique description and textbooks promote surgical excision as a gold standard treatment. Surgical excision is described as the most definitive mode of treatment for symptomatic Morton?s neuroma with reported success rates varying between 79% and 93%. Various surgical techniques are described, essentially categorised as dorsal versus plantar incision approaches. Beyond this the commonest technical variation described as influencing the outcome of surgery involves burying and anchoring transacted nerve into soft tissue such as muscle.
Ensuring that shoes are well fitted, low-heeled and with a wide toe area may help to prevent Morton's neuroma.