Put simply – Morton’s neuroma is a swollen (inflamed) nerve in the ball of the foot, commonly between the base of the second and third toes. Patients experience numbness and pain in the affected area, which is relieved by removing footwear and/or massaging the foot. A neuroma is a tumor that arises in nerve cells, a benign growth of nerve tissue that can develop in various parts of the body. In Morton’s neuroma the tissue around one of the nerves leading to the toes thickens, causing a sharp, burning pain in the ball of the foot. A sharp severe pain, often described as a red hot needle may come on suddenly while walking. There may also be numbness, burning and stinging in the toes. Although it is labeled a neuroma, many say it is not a true tumor, but rather a perineural fibroma (fibrous tissue formation around nerve tissue).
The cause of this problem is often due to impingement of the plantar nerve fibres between the metatarsal heads and the intermetatarsal ligament. It is entirely a biomechanical phenomenon. Differential diagnoses include stress fracture, capsulitis, bursitis or ligament injury at the metatarsal-phalangeal joint, a tendon sheath ganglion, foreign-body reaction and nerve-sheath tumour.
A Morton’s neuroma usually causes burning pain, numbness or tingling at the base of the third, fourth or second toes. Pain also can spread from the ball of the foot out to the tips of the toes. In some cases, there also is the sensation of a lump, a fold of sock or a “hot pebble” between the toes. Typically, the pain of a Morton’s neuroma is relieved temporarily by taking off your shoes, flexing your toes and rubbing your feet. Symptoms may be aggravated by standing for prolonged periods or by wearing high heels or shoes with a narrow toe box.
The doctor will ask about your symptoms and medical history. A physical exam will be done. Initial diagnosis of Morton’s neuroma is based on your description of the type and location of pain and discomfort in the foot. The diagnosis will be confirmed by a physical exam of the foot, including checking for mechanical abnormalities in the foot, squeezing the side of the foot, which will usually cause pain when Morton’s neuroma is present. Examination of your shoes to check for excess wear in parts of the shoe, check to see whether the shoes are too tight. Imaging tests evaluate the foot and surrounding structures. This may be done with X-ray, MRI scan, Ultrasound. Injections of local anesthetic can also be used for diagnosis.
Non Surgical Treatment
Most patients’ symptoms subside when they change footwear to a wide soft shoe with a metatarsal support inside to relieve the pressure on the involved area. If this treatment fails, a cortisone injection into the nerve is occasionally helpful.
If your pain continues despite several months of conservative treatment, your doctor may recommend surgery to remove the neuroma or to widen the space through which the affected nerve travels. These types of surgery often are done under local anesthesia. If your doctor removes a portion of the affected nerve along with the neuroma, you may develop permanent numbness between the toes.