What is a Morton Neuroma?
A Morton’s Neuroma is a painful, inflamed and enlarged nerve in the foot. It is one of the causes of metatarsalgia (pain in the ball of the foot). The inflammation is caused by entrapment of the nerve by the bones and/or soft tissue ligaments of the foot. The word ‘neuroma’ means nerve tumour. In this case, the word neuroma simply means enlargement of the nerve. It is not a dangerous condition, and does not mean cancer or malignancy.
What are the symptoms?
The symptoms include pain and numbness which can start at the ball of the foot and often spread in the toes. Removal of shoes can relieve some of the symptoms and the symptoms are often worse in shoes. There may be a feeling of a marble or pebble in the foot and can sometimes cause a ‘snap’ or clicking sensation with electric shocks into the toes. The symptoms can come and go over many years. In some cases, the symptoms can be regular and persistent (chronic).
How is it diagnosed?
The diagnosis is often made on clinical history and examination. Diagnosis can sometimes be difficult, and there may be other conditions that mimic a Morton’s neuroma. If there is any doubt, then further investigations maybe undertaken to confirm the diagnosis. Sometimes a Morton’s neuroma may be present on imaging but not actually causing symptoms and occasionally a neuroma is caused by other foot problems rather than being the cause of the foot problem. In these instances the treatment of your symptoms may therefore be targeted at other issues in the foot rather than focusing on the neuroma itself.
What are the treatment options?
Initial treatment is to modify footwear, which involves wearing soft and wide fitting shoes. Insoles maybe helpful to pad the ball of the foot and relieve some of the pressure on the foot.
A steroid injection is often helpful in relieving symptoms. Often patients need 1 or 2 injections to gain long term pain relief. This is in combination with footwear modifications and/or insoles.
If the symptoms do not settle with the above treatments, then surgery is an option. The surgery involves removing the nerve which removes the painful neuroma and leaves the area permanently numb.
What are the benefits of surgery?
The surgery is successful in over 80% of cases. The aim of surgery is to relieve the pain in the foot. As the nerve is removed, there will be permanent numbness in the toes afterwards. This usually does not cause problem with function.
Summary of surgery.
The surgery is usually performed as a day case. It is usually performed under a general anaesthetic. Local anaesthetic is often given at the end of the surgery to help with pain relief afterwards. A cut is made on the top of the foot and the nerve is surgically removed.
After your surgery
Your foot will be in a bulky bandage and you will be provided with a post-surgical shoe. You should keep your foot elevated on a chair/pillow and take regular painkillers as per the “Advice after Surgery” section below.
What are the risks with surgery?
The general risks with surgery include
Bleeding – rarely there may be bleeding which results in a collection of blood under the wound. Bruising is common after this procedure
Swelling – common after surgery and can take many months to eventually settle down. Elevation is key to reducing this.
Stiffness – exercises are important to reduce the stiffness in the toes after surgery
Infection – the risk is 1-2%. Superficial infections can be treated with antibiotics. Deeper infections which are much rarer may require further surgery.
Numbness - As the nerve is removed, there will be permanent numbness in the toes afterwards. This usually does not cause problem with function.
Scarring – some scars can be prominent or dark in colour. This usually fades with time.
Clots in leg/lung – your risk of clots will be assessed prior to surgery and appropriate treatment/advice will be given.
The specific risks to this surgery include
Persistent pain – this may be due to irritation of the nerve where it has been cut – a stump neuroma. This may require repeat surgery.
Damage to blood vessels. The nerve is immediately adjacent to the blood vessel to the toe and, whilst care is taken to protect the vessel, damage can rarely occur. If this happens the toe will usually happily survive from the vessel in the adjacent webspace such that loss of a toe is incredibly rare indeed. This is the reason why it is not possible to operate on more than one neuroma at a time – to avoid the risk of damaging both vessels to the toe.
Chronic regional pain – This is excessive pain after surgery and is a very rare complication.
Advice after surgery
The foot should be strictly elevated for the first 2 weeks to avoid excessive swelling which could compromise the wound. Aim to keep the foot elevated for 55 minutes of every hour
The dressings should not be disturbed unless there is a concern with the wound. At around 2 weeks after surgery, you will return to the clinic to have the bandages and stitches removed. After this the wound can be dressed with a simple light dressing.
You may shower after the stitches have been removed and the wound is fully healed. Keep the wound and surrounding area dry and clean.
You are allowed to bear weight in the post op shoe. You may need crutches. The physiotherapist will show you how to use them. You may need to wear the shoe for 3-4 weeks. After this time, you can wear flat soled shoes.
It may take several weeks before you can drive. Please check with your insurer.
Going back to work depends on the activity undertaken at work and should be discussed with your surgeon.
Most people go back to recreational walking and light activities approximately 4-6 weeks after surgery. It may take several months before swelling subsides. This is a normal recovery. Often a full recovery takes much longer than one would expect. If you are slower than these times do not panic, they are only averages, but let your surgeon know when you attend clinic.
If I have any questions or concerns?
These guidelines are to help you understand your operation. This level of detail may cause concern, anxiety, or uncertainty. Please let your doctor or nurse know so that we may address these issues.
We aim to see you back in the clinic at regular intervals to monitor your progress and answer any questions you may have during your recovery.
If there is concern regarding the wound, such as increased redness, pus, discharge, or pain, then seek medical attention either at your GP or nearest Emergency department.
Above all else, please do not proceed with surgery unless you are satisfied and understand all you want to know about the operation.