Morton's neuroma is named after Dr Morton who first described this condition in 1876. It is sometimes called Morton's metatarsalgia or interdigital neuroma. It is a condition that affects one of the common plantar digital nerves that run between the long bones (metatarsals) in the foot. It most commonly affects the nerve between the third and fourth metatarsal bones, causing pain and numbness in the third and fourth toes. It can also affect the nerve between the second and third metatarsal bones, causing symptoms in the second and third toes. Morton's neuroma rarely affects the nerve between the first and second, or between the fourth and fifth, metatarsal bones. It tends to affect only one foot. It is rare to get two neuromas at the same time in the same foot.
Morton's Neuroma is a caused by pressure, abnormal function/motion or an imbalance in the structure of the foot such as flat feet, that causes an abnormal pressure on the structures and the nerves in the ball of the foot. It most commonly affects the nerve that goes to the 2nd 3rd or 4th toes. The squeezing of the nerve from abnormal motion leads to a protective thickening of the sheath that protects the nerve. Symptoms of Morton's Neuroma often occur during or after activities that cause a sidewards squeezing of the ball of the foot or from pressure such as walking, standing, or playing sport. Since squeezing is a common cause of the condition, shoes such as pointed toes or high heels can often lead to a neuroma. Shoes that are constricting, even tight sneakers, can pinch the nerve between the toes, causing inflammation and pain.
Pain is usually increased by forefoot weight bearing activities (such as running), with narrow-fitting footwear, or with high heeled shoes. It is usually painful to firmly touch the affected region and, in chronic cases, pain and sometimes an audible click, may be heard when squeezing the foot and toes together with the hand. Often a localized area of swelling may be evident at the site of injury.
The diagnosis of interdigital neuroma is usually made by physical examination and review of the patient's medical history.MRI ad High Definition Ultrasound examination may be useful to confirm the diagnoses however they may still not be 100% reliable. The commonest reason for this is de to natural substances present in between the metatarsal heads and between the fat pad and the intermetatarsal ligament. These natural substances i.e. bursa, fat, capsular thickening and even bony growths, can all be a factor in the impingement process and may need to be surgically cleared.
Non Surgical Treatment
You may be able to treat this problem at home. Avoid wearing tight, pointy, or high-heeled shoes. Choose well-fitted shoes with plenty of room for your toes. Put ice or a cold pack on the area for 10 to 15 minutes at a time. Put a thin cloth between the ice and your skin. Take anti-inflammatory medicines to reduce pain and swelling. These include ibuprofen (such as Advil or Motrin) and naproxen (such as Aleve). Rest your feet when you can. Reduce activities that put pressure on the toes, such as racquet sports or running. Try massaging your foot to relax the muscles around the nerve. If these steps do not relieve your symptoms, your doctor may have you use special pads or devices that spread the toes to keep them from squeezing the nerve. In some cases, a doctor may give a steroid shot to reduce swelling and pain. If these treatments do not help, your doctor may suggest surgery.
If other therapies have not worked it may be necessary to perform surgery. As surgery may result in permanent numbness in the affected toe, doctors ten to use this procedure as a last resort. However, in most cases surgery is extremely effective. The patient usually receives a local anesthetic. Surgery involves either removing the nerve, or removing the pressure on the nerve. Two surgical approaches are possible. The dorsal approach, the surgeon makes an incision on the top of the foot, allowing the patient to walk soon after surgery, because the stitches are not on the weight-bearing side of the foot. The plantar approach, the surgeon makes an incision on the sole of the foot. In most cases the patient will be in crutches for about three weeks. The resulting scar may make walking uncomfortable. However, with this approach the neuroma can be reached easily and resected without cutting any structures. There is a small risk of infection around the toes after surgery.