Morton’s neuroma
Morton’s neuroma
Morton’s neuroma
Morton’s neuroma
What is a Morton’s neuroma?
Morton’s neuroma is a thickening of the tissues that surrounds the sensory nerves (aka interdigital nerves) that give sensation to the toes. They usually occur between the second and third toes, or the third and fourth toes. Around 1 in 3 people will experience a Morton’s neuroma, and they are most common in middle-aged women.
What causes Morton’s neuroma?
Morton’s neuromas are caused by repetitive compression and irritation of the nerves where they pass under a ligament deep within the foot.
There’s some evidence that shows that tight shoes, especially high heels, causes crowding of the toes and the metatarsal heads that causes compression of the nerve. Some high impact sports like jumping or running sometimes can cause them.
Foot deformities, such as bunions, high-arched or very flat feet, can increase the likelihood of a neuroma forming.
Inflammatory conditions (such as rheumatoid and psoriatic arthritis) can also increase the risk of developing a Morton’s neuroma, as can previous trauma to the foot.
If you’re overweight or spend a great deal of time standing in your work, you’re more likely to develop a Morton’s neuroma.
What are the symptoms of Morton’s neuroma?
Pain on weight bearing is the main symptom of a Morton’s neuroma, and it’s usually felt in the ball of the foot, but it may also spread to the toes. It can feel like a burning or shooting sensation, but some patients will also experience tingling or numbness between the affected toes.
It may feel like you have stepped on a stone, or that there is a wrinkle in your sock, and you may be able to relate it to wearing high heels or tight-fitting shoes.
Many people also experience a clicking sensation when loading the foot.
How is Morton’s neuroma diagnosed?
Making a diagnosis of Morton’s neuroma considers the history as well as the clinical examination findings. Squeezing across the toes applies pressure on the webspace, which can reproduce the pain, and a click may be heard, called a Mulder’s sign.
Not all pain in the forefoot is a neuroma, and investigations are sometimes required to confirm the diagnosis, usually in the form of an ultrasound scan or an occasional MRI scan.
Treatment for Morton’s neuroma
We typically begin with footwear modification. Wearing shoes with a lower heel and a wider toe box can help alleviate the problem. Occasionally we may use orthotics (a special insole in the shoe), or a metatarsal pad to offload the neuroma.
The next stage are injections (steroid with local anaesthetic) to try and reduce the inflammation and pain, but they need to be used in conjunction with the other measures (such as avoiding high heel or pointy shoes).
If all of the above does not work, then surgery is an option. Surgery involves excision of the thickened nerve ending and release of the ligament that the nerve runs under. The pain usually improves immediately; however, patients are left with reduced sensation in the webspace.
Sometimes the neuroma presents in two neighbouring web spaces. If that’s the case, it’s better not to operate on both neuromas at the same time, due to the risk of potential damage to the blood vessels which can threaten the toes. To minimise this risk, the neuromas would be surgically removed on separate occasions.
If there is an accompanying deformity of the foot, it’s always advisable for that to be addressed as well. This may mean correcting a bunion or a hammer toe, to reduce the risk of future neuromas forming.
Can a Morton’s neuroma grow back?
I take care to ‘bury’ the proximal end of the nerve in muscle to reduce the chance of a ‘stump’ neuroma developing after the excision of the original neuroma. Most neuroma excisions are highly successful; it’s possible that a ‘stump’ neuroma could occur after surgery, but I never had seen this in any of my patients.
What is recovery like after Morton’s neuroma surgery?
Recovery is swift. You’ll be weight bearing immediately after the surgery (wearing a dressing), and at 2-3 weeks your dressing will be removed. You can then resume your normal activities.
