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.
Pronation of the foot can cause the metatarsal heads to rotate slightly and pinch the nerve running between the metatarsal heads. This chronic pinching can make the nerve sheath enlarge. As it enlarges it than becomes more squeezed and increasingly troublesome. Tight shoes, shoes with little room for the forefoot, pointy toeboxes can all make this problem more painful. Walking barefoot may also be painful, since the foot may be functioning in an over-pronated position.
Feelings of numbness, tingling or tenderness in the ball of the foot (the area just behind the base of the toes) are some of the first signs of a condition known as Morton?s Neuroma. However, the condition is somewhat unpredictable, and symptoms may vary from patient to patient. Generally, however, the discomfort gets worse rather than better, and the patient may feel pain or a burning sensation that radiates out to the toes. Eventually, wearing shoes becomes uncomfortable (or even unbearable), and the patient may complain that the feeling is similar to that of having a stone bruise, or walking on a marble or pebble constantly, even though no there is no trauma to the skin, and no visible bump or lump on the sole of the foot.
Patients with classic Morton?s neuroma symptoms will have pain with pressure at the base of the involved toes (either between the 2nd and 3rd toes, or between the 3rd and 4th toes). In addition, squeezing the front of the foot together can exacerbate symptoms. As well, they may have numbness on the sides of one toe and the adjacent toe as this corresponds with the distribution of the involved nerve.
Non Surgical Treatment
Treatment for Morton?s neuroma will depend on how long you've had the condition and its severity. Simple non-surgical treatments are effective for some people. Others may need surgery. If Morton's neuroma is diagnosed early, treatment will aim to reduce the pressure on the affected nerve. This is usually the nerve between the third and fourth toe bones (metatarsals). Your GP or podiatrist (foot specialist) may recommend changing the type of shoes you usually wear, shoes with a wider toe area may help ease the pressure on the nerve in your foot. Using orthotic devices, such as a support for the arch of your foot to help relieve the pressure on the nerve. Anti-inflammatory painkillers or a course of steroid injections into the affected area of your foot may help ease the pain and inflammation. Alcohol and local anaesthetic is injected into your foot using ultrasound for guidance, studies have shown that this type of treatment is effective. Resting your foot and massaging your toes may also help to relieve the pain. You can make an ice pack by freezing a small bottle of water and rolling it over the affected area.
Surgery for Morton's neuroma is usually a treatment of last resort. It may be recommended if you have severe pain in your foot or if non-surgical treatments haven't worked. Surgery is usually carried out under local anaesthetic, on an outpatient basis, which means you won't need to stay in hospital overnight. The operation can take up to 30 minutes. The surgeon will make a small incision, either on the top of your foot or on the sole. They may try to increase the space around the nerve (nerve decompression) by removing some of the surrounding tissue, or they may remove the nerve completely (nerve resection). If the nerve is removed, the area between your toes may be permanently numb. After the procedure you'll need to wear a special protective shoe until the affected area has healed sufficiently to wear normal footwear. It can take up to four weeks to make a full recovery. Most people (about 75%) who have surgery to treat Morton's neuroma have positive results and their painful symptoms are relieved.