Exactly what causes Morton's neuroma is not always known, but there are several things that seem to aggravate it. These include other foot-related problems and wearing restrictive footwear.
It is thought that Morton's neuroma may be caused by the toe bones (metatarsal bones) pressing against the nerve when the gap between the bones is narrow. This causes the nerve and surrounding tissue to thicken.
Footwear
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 those that have a pointed or tight toe area, can also compress the toes and make the pain worse. This is why women tend to be affected by the condition more than men.
Foot conditions
Some experts also believe that other foot conditions may be associated with Morton's neuroma. This is because other conditions may cause the metatarsal bones to rub against the nerve in your foot.
Foot problems that may increase your risk of developing the condition include:
- abnormally positioned toes
- high arches – where the arch or instep of your foot is raised more than normal
- flat feet – low arches or no arches at all
- bunion – a bony swelling at the base of the toe
- hammer toe – where the toe is bent at the middle joint
Sporting activities
Being active and playing sport can make the painful symptoms of Morton's neuroma worse.
In particular, running or sports that involve running (such as racquet sports) can place extra pressure on the nerve in your foot, which can aggravate the problem.
