Morton’s neuroma is an enlarged nerve that usually occurs in the third interspace, which is between the third and fourth toes. To understand Morton’s neuroma further, it may be helpful to look at the anatomy of the foot. Problems often develop in the third interspace because part of the lateral plantar nerve combines with part of the medial plantar nerve here. When the two nerves combine, they are typically larger in diameter than those going to the other toes. Also, the nerve lies in subcutaneous tissue, just above the fat pad of the foot, close to an artery and vein. Above the nerve is a structure called the deep transverse metatarsal ligament. This ligament is very strong, holds the metatarsal bones together, and creates the ceiling of the nerve compartment. With each step, the ground pushes up on the enlarged nerve and the deep transverse metatarsal ligament pushes down. This causes compression in a confined space.
Wearing shoes that are too tight can make the pain of Morton’s neuroma worse. This is because the toe bones are more likely to press on the affected nerve if your shoes are too tight. High-heeled shoes, particularly those over 5cm (2 inches), or shoes with a pointed or tight toe area, can also compress your toes and make the pain worse. This is why women tend to be affected by Morton’s neuroma more than men.
If you have a Morton?s neuroma, you may have one or more of these symptoms where the nerve damage is occurring, Tingling, burning, or numbness, pain, a feeling that something is inside the ball of the foot or a feeling that there?s something in the shoe or a sock is bunched up. The progression of a Morton?s neuroma often follows the following pattern. The symptoms begin gradually. At first they occur only occasionally, when wearing narrow-toed shoes or performing certain aggravating activities. The symptoms may go away temporarily by removing the shoe, massaging the foot, or by avoiding aggravating shoes or activities. Over time the symptoms progressively worsen and may persist for several days or weeks. The symptoms become more intense as the neuroma enlarges and the temporary changes in the nerve become permanent.
The most common condition misdiagnosed as Morton’s neuroma is metatarsophalangeal (MTP) joint synovitis. When pain occurs in the third interspace, the clinician may misdiagnose the condition as Morton’s neuroma instead of MTP synovitis, which may manifest very much like Morton’s neuroma. MTP synovitis is distinguished from Morton’s neuroma by subtle swelling around the joint, pain localized mainly within the joint, and pain with forced toe flexion. Palpation of the MTP joint is performed best with a pinching maneuver from the dorsal and plantar aspects of the joint to elicit tenderness of the joint. Other conditions often misdiagnosed as Morton’s neuroma include the following. Stress fracture of the neck of the metatarsal. Rheumatoid arthritis and other systemic arthritic conditions. Hammertoe. Metatarsalgia (ie, plantar tenderness over the metatarsal head) Less common conditions that have overlapping symptoms with Morton’s neuroma include the following. Neoplasms. Metatarsal head osteonecrosis. Freiburg. steochondrosis. Ganglion cysts. Intermetatarsal bursal fluid collections. True neuromas.
Non Surgical Treatment
Ice therapy and anti-inflammatory medications or supplements. If conservative care measures fail to resolve your problem, some foot care providers may recommend a cortisone injection around your involved nerve to help reduce your swelling and inflammation. Concentrated alcohol injections around your affected nerve have also shown good results and should be considered before undergoing neurectomy, a surgical procedure to remove the enlarged, traumatized portion of your involved nerve.
If these non-surgical measures do not work, surgery is sometimes needed. Surgery normally involves a small incision (cut) being made on either the top, or the sole, of the foot between the affected toes. Usually, the surgeon will then either create more space around the affected nerve (known as nerve decompression) or will cut out (resect) the affected nerve. If the nerve is resected, there will be some permanent numbness of the skin between the affected toes. This does not usually cause any problems. You will usually have to wear a special shoe for a short time after surgery until the wound has healed and normal footwear can be used again. Surgery is usually successful. However, as with any surgical operation, there is a risk of complications. For example, after this operation a small number of people can develop a wound infection. Another complication may be long-term thickening of the skin (callus formation) on the sole of the foot (known as plantar keratosis). This may require treatment by a specialist in care of the feet (chiropody).
Women, particularly those who wear tight shoes, are at greatest risk for Morton?s neuroma. The best way to prevent the condition is to wear shoes with wide toe boxes. Tight, pointed shoes squeeze bones, ligaments, muscles and nerves. High heels may worsen the problem by shifting your weight forward. Over time, this combination can cause the nerves to swell and become painful.