Morton’s neuroma is an inflamed nerve that causes pain, tingling, and numbness in the ball of the foot. Many complain of a sock bunching up under the ball of their foot, while others complain of walking on a lump, large rock, or lamp cord. Some describe a “twang,” like a guitar string, on the bottom of the foot. The pain may be cushioned in the ball of the foot, or it may be radiating, electric, tingling, or burning, shooting up to the third and fourth toes. The pain worsens with tight shoes, standing, walking, hills, and stairs and is usually relieved by rest and removing shoes.
The initial treatment of Morton’s neuroma is to eliminate the factors that may have caused or aggravated it. In many cases, tight shoes cause toe cramps and put pressure on the nerve, causing irritation, inflammation, and pain. Overpronation causes instability in the forefoot and excess movement of the long bones of the foot. This type of abnormal foot mechanics, in combination with soft, flexible shoes, can cause a neuroma.
Applying ice to the ball of the foot twice a day for 15 minutes and/or contrasting hot and cold for 30 minutes each day will help decrease inflammation. Anti-inflammatory medications, such as ibuprofen or naproxen, can also decrease inflammation and pain. A neuroma pad will help disperse pressure from the forefoot, which will decrease irritation to the nerve. Steroid injections and nerve sclerosis injections can also be used.
When conservative therapy fails, surgery is recommended. Surgery involves releasing the ligament by putting pressure on the nerve or removing the neuroma. When the neuroma is removed, permanent numbness will occur in the toes, but the function of the fingers will not be affected.
In a new study published in the Journal of the American Podiatric Medical Association, researchers found that extracorporeal shock wave therapy is a safe and effective treatment for Morton’s neuroma. Extracorporeal Shock Wave Therapy (ESWT) is a treatment that directs powerful sound waves at the area of injury. Sound waves create vibrations that cause microtrauma to tissues.
The body responds by creating new blood vessels and sending healing factors and inflammatory cells to the area to stimulate the natural healing process. ESWT has been used for the treatment of kidney stones for many years. In 2000, the FDA approved ESWT for the treatment of chronic plantar fasciitis, a painful heel condition. ESWT is not currently approved for the treatment of neuromas.
In this study, the investigators divided twenty-five patients with Morton’s neuroma, who had not responded to at least eight months of conservative therapy, into an active treatment group or a sham treatment group. Both groups were brought to the procedure room and given intravenous sedation and local anesthesia. The active treatment group received extracorporeal shock wave therapy and the sham group received no treatment.
At 12 weeks post-procedure, the extracorporeal shock wave therapy group had a significant reduction in pain compared to the sham group. Potential complications associated with extracorporeal shock wave therapy include bruising, pain, swelling, nerve damage, and bleeding, but the incidence is less than 1%. The results of this study are encouraging and TOCH may prove to be an effective alternative treatment to surgery. But this is a small study, and more research is needed to evaluate the safety and effectiveness of extracorporeal shock wave therapy for the treatment of Morton’s neuroma.
Fridman R, Cain JD, Weil L. Extracorporeal shock wave therapy for interdigital neuroma. A randomized, placebo-controlled, double-blind trial. JAPMA. Vol 99, No 3, May/June 2009.