Morton's neuroma: A swollen inflamed nerve in the ball of the foot, usually between the base of the second and third toes (known as the third intermetatarsal space), caused by chronic compression of a branch of the plantar nerve between the ends of the metatarsal bones. The disorder is especially common in women who wear high-heeled and/or narrow shoes.
Morton's neuroma causes a stinging sharp pain on the bottom of the foot that can radiate to the nearby toes. The pain may be increased by walking or when the ball of the foot is squeezed together; and the pain may be decreased with massaging. The diagnosis is made from the history of pain and examination elicits it. Magnetic resonance imaging (MRI) or ultrasound can confirm the diagnosis.
The symptoms can completely resolve with simple treatments: resting the foot, better fitting shoes with low or no heels and a wide toe box, a domed insert in the shoe to support the metatarsal arch, anti-inflammation medications, and ice packs. Rapid relief of symptoms can follow a local cortisone injection. For those with persistent symptoms, the swollen nerve tissue may be removed by surgery. This condition is named for the American surgeon Thomas George Morton (1835-1903), whose father was the dentist who discovered the anesthetic effect of ether.