Nerve Pain

Neuroma

A neuroma is a benign tumor of a nerve. It can affect any nerve in the body. It is sometimes refereed to as a pinched nerve. The most common in the foot is Morton’s neuroma.

Morton’s neuroma is not actually a tumor – it is really a thickening of the tissue surrounding nerve leading to the toes. The swelling of the nerve is often the cause of symptoms.

 

Burning Foot / Feet

 

What is the burning foot:

Burning feet are a common complaint and can be caused by a number of conditions – some are local and minor, and some are more serious. Burning feet can keep people awake at night and be a source of continuous pain. It is more common in those over the age of 50 years, but a burning foot can occur in younger age groups. Burning feet are more common in those with diabetes as part of the neuropathy (nerve damage) that can develop. A burning foot may be mild and local and easily treatable or it may indicate a more serious general medical problem that needs further investigation.

“Its like walking on hot coal !!!”

What causes a sensation of burning feet:

The more common causes of burning feet are:

* many feet just ache and burn at the end of a long day, especially in those who are on their feet all day or are overweight (mechanical overload)

* hot and sweaty feet can cause a burning foot sensation (and may be related to the mechanical overload problem)

* the neuropathy that occurs in diabetes can cause a burning feet

* other types of neuropathy (nerve damage) that can cause a burning foot include those that occur in chronic alcoholism, vitamin deficiencies (usually B) and heavy metal poisoning

* blood disorders (eg thrombocytopenia, pernicious anemia) can cause burning feet

* Erythromelalgia is a rare circulatory disorder can can cause burning feet

* Reflex sympathetic dystrophy or complex regional pain syndrome can follow trauma (including surgery) and cause a burning foot sensation

* nerve entrapments, such as tarsal tunnel syndrome, which is the compression of a nerve at the inside of the ankle joint can cause a burning sensation

* a localized burning sensation may be due to other specific problems. If its in the forefoot only, it could be metatarsalgia, Morton’s neuroma or some other cause. Athletes foot or a fungal infection can also cause a burning sensation in the area of the infection.

* it could also be due to a sensitivity to chemical substances in socks and shoes (contact dermatitis)

Self treatment of the burning foot sensation:

The most important part of managing burning feet yourself is to get it checked to make sure it is not caused by one of the rare serious problems.

Once the cause is established, there are a number of things that you can do to help your burning feet, but this can depend on the cause:

* if its mechanical, good fitting shoes with support is a good place to start to help.

* if hot and sweaty, there are various self treatments for the sweaty foot

* some creams or ointments with cooling properties can help relieve the symptoms

* some relief in some people has been shown to occur with the use of magnets

* wear socks made of cotton rather than synthetic fabrics

* bath feet in cool water

* avoid prolonged period of standing

* cushioning or shock absorbing insoles may make standing more tolerable

There is a lot of advice on the internet to take vitamin B12 to help burning feet. However, a burning foot occuring with the neuropathy that is associated with a deficiency of vitamin B12 is very uncommon and should be managed by a medical doctor. The taking of B12 for burning feet is not likely to help unless a deficiency is the cause and its is one of the more uncommon causes of the burning foot.

Treatment of the burning foot sensation:

Treatment of burning feet needs the cause to be established, so consultation with a Podiatrist, rheumatologist (arthritis doctor) or a neurologist (nerve doctor) is important. A full range of tests may need to be ordered to determine the cause if it is not simply a mechanical overload that is the problem.

Treatment of a mechanical overload problem with foot supports or orthotics are usually very successful in helping the mechanical overload (they will not help if mechanical overload is not the cause of the burning feet). Other local causes such as a fungal infection, nerve entrapment and sweaty feet can be also be treated.

Treatment of underlying conditions may bring relief (but this will depend on the cause).

Pain relief medication may be needed for the treatment of any of the chronic causes of burning feet.

If the problem is chronic, strategies to help manage the symptoms will need to be discussed

 

Tarsal tunnel syndrome

Tarsal tunnel syndrome is a condition that is caused by the entrapment of the tibial nerve on the inside of the ankle.

There are some very tight structures in this area, so there is very little room for expansion if any of these structures becomes inflamed or enlarged. This inflammation or enlargement of the nerve in this area causes the entrapment.

When this entrapment compresses the nerve, it can cause pain, burning sensations, and tingling on the sole of the foot. This usually worsens as the day progresses and is usually relieved by rest, elevation, or rubbing the area. The diagnsis of tarsal tunnel syndrome is sometimes made using nerve conduction tests.

Cause of tarsal tunnel syndrome:

A number of factors are involed in the cause if tarsal tunnel syndrome:

the nerve ‘bends’ around behind the inner ankle bone (medial malleolus) – this bend in the nerve does make it more prone to damage in this area.

structures that are adjacent to the nerve can compress the nerve if they become swollen (eg tendon)

people with very flat or pronated feet are more prone to develop tarsal tunnel syndrome.

a cyst or other lesion may develop in the area

some systemic diseases, such as rheumatoid arthritis can cause a swelling in joints that may compress on the nerve.

trauma or fractures causing a malalignment or the development of scar tissue can also affect how the nerve functions and the pressures on it.

Treatment of tarsal tunnel syndrome:

Conservative treatment generally consists of the use of some sort of foot support, which can often help, especially if the feet are very flat. Anti-inflammatory drugs may be used. Sometimes steroid injections can be effective. Surgical treatment may be necessary if these conservative measures are ineffective. An incision is made into the tissues to allow room for expansion of the nerve or for removal of a cyst or other structure that is compressing the nerve.

 

Peripheral Neuropathy

Peripheral neuropathy is the general term that refers to disorders of peripheral nerves. The peripheral nervous system is made up of the nerves that branch out of the spinal cord to different parts of the body.

Peripheral neuropathy is a relatively common neurological disorder that results from damage to the peripheral nerves. It can be caused by a number of diseases of the nerves or be the result of systemic illnesses. Many of the peripheral neuropathy’s have a well established cause such as diabetes, alcoholism, uremia, AIDs, or nutritional deficiencies. Diabetes is, by far, one of the most common causes of peripheral neuropathy. Other less common causes include exposure to cold or radiation, a few medicines, toxic substances, vascular or collagen disorders, systemic lupus erythematosus, scleroderma and rheumatoid arthritis.

Symptoms of peripheral neuropathy:

The peripheral nervous system consists of motor (to help move) nerves and sensory (to help feel) nerves. Either or both sets of nerves can be affected in neuropathy.

If a sensory nerve is damaged, the predominant symptoms are pain, numbness, tingling, burning or a loss of feeling. They often begin gradually. There may be a tingling sensation or numbness that starts in the toes and/or the balls of the feet and spreads upward. Occasionally the skin may become so sensitive that the slightest touch is agonizing. There may also may be a numbness, or a complete lack of feeling in the feet. At times the symptoms may be barely noticeable and at other times, especially at night, they may be almost unbearable. The symptoms may also include a sensation that you’re wearing an invisible glove or sock; a burning or freezing pain; sharp, jabbing or electric pain; and an extreme sensitivity to touch.

If the motor nerves are damaged there may be a weakness or paralysis of the muscles controlled by the affected nerve(s). In the foot their may be a ‘wasting’ of the muscles as they do not work as well as before.

Diabetic peripheral neuropathy:

Diabetic neuropathy deserves special mention as it is the most common type and can lead to serious complications in those with diabetes. Diabetic peripheral neuropathy means damage of nerve fibres in people with diabetes. The process by which the nerves are damaged is not entirely clear but it is probably related to high blood glucose changes that affect the metabolism of nerve cells.

There are three types of diabetic peripheral neuropathy:

sensory (loose the ability to detect sensations such as heat, cold, pain)
motor (loss of strength to control movement)
autonomic (regulate functions such as heart rate and digestion)

Diabetic peripheral neuropathy can result in two types of problems:

there can be a loss of ability to feel pain and other sensations – this puts the foot at risk of being damaged and not knowing about it

there can be symptoms of pain and burning leading to discomfort (painful neuropathy).

Treatment of peripheral neuropathy:

The treatment for peripheral neuropathy will differ, depending on the cause. For example, if it is caused by diabetes the therapy involves better control of the diabetes. If it is caused by a vitamin deficiency, then supplementation will help.

Medications, such as pain relievers and tricyclic antidepressants are often helpful.

Generally, the treatment for peripheral neuropathy is unsatisfactory and often only symptomatic relief is available. Some of these include transcutaneous electrical nerve stimulation, acupuncture and biofeedback.

Protection of the foot in peripheral neuropathy:

As a loss of sensation (numbness) is common in peripheral neuropathy, damage to the foot can go undetected and lead to serious complications (especially in those who also have diabetes). It is best to protect the foot with good fitting footwear and the foot should be inspected daily for damage. Particular attention should be paid to corns and calluses, as these may need treatment by a podiatrist.