What causes "phantom limb"?

When a limb has been amputated, the main neural pathway may still be intact to that limb. Your nervous system branches down, with more nerve endings at the distal end (the furthest point- like fingers, toes etc.) and the main pathway runs to your spinal column. Neural activity continues in the areas which remain and can cause impulses of sensation to be interpreted as coming from the limb which is no longer there.

Phantom limb is a phantom sensation in amputated or missing limbs. A phantom sensation is a feeling that a missing limb is still attached to the body and is moving appropriately with other body parts. Approximately 50 to 80% of amputees experience these phantom sensations in their amputated limb. Phantom sensations and phantom pain may also occur after the removal of body parts other than the limbs, e.g. after amputation of the breast, extraction of a tooth (phantom tooth pain) or removal of an eye (phantom eye syndrome).

Phantom pains can also occur in people who are born without limbs and people who are paralyzed. Phantom pains occur when the missing limb causes discomfort. Some other sensations include warmth, cold, itching, squeezing and burning. The missing limb often feels shorter and may feel as if it is in a distorted and painful position. Occasionally, the pain can be made worse by stress, anxiety and weather changes.

Some treatments include drugs such as antidepressants. Spinal cord stimulation (SCS) can be a very effective treatment for phantom pain. An electrical stimulator is implanted under the skin, and an electrode is placed next to the spinal cord. The nerve pathways in the spinal cord are stimulated by an electric current. This interferes with the impulses travelling towards the brain and lessens the pain felt in the phantom limb. Instead, amputees feel a tingling sensation in the phantom limb.

Vibration therapy, acupuncture, hypnosis and biofeedback may all be used to treat phantom pain but are often of little help. The pain can sometimes be helped by keeping busy and occupying your mind. Massaging the stump can sometimes help. The pain can often be prevented by the application of not only a general but also a local anaesthesia while amputating a limb

I think its because you brain is used to you having that limb, and doesnt realise that it has gone?

The remaining portion of nerves from the severed limb still sending signals to the brain, making you feel as if that limb is still there.

Phantom limb syndrome: The perception of sensations, usually including pain, in an arm or leg after the limb has been amputated. The brain still gets messages from the nerves that originally carried impulses from the missing limb. Phantom limb syndrome is relatively common in amputees, especially in the early months and years after limb loss.

Phantom limb pain


Jonathan Cole

Phantom limb pain 鈥?pain appearing to come from where an amputated limb used to be 鈥?is often excruciating and almost impossible to treat. New approaches, based on a better understanding of the brain's role in pain, may be opening the way to new treatments.


After amputation of a limb, an amputee continues to have an awareness of it and to experience sensations from it. These phantom limb sensations are also present in children born without a limb, suggesting that perception of our limbs is 'hard-wired' into our brain and that sensations from the limbs become mapped onto these brain networks as we develop.

If phantom limb sensations are normal then so too, alas, is phantom limb pain. This occurs in a majority of those who lose their limbs. (1) In fact, limbs do not need to be lost; it also occurs in conditions in which the brain is disconnected from the body, such as peripheral nerve injuries and after spinal cord injury, when an area becomes insentient (and usually paralysed).

The pain is described in various ways: burning, aching, 'as if the hand is being crushed in a vice,' etc. Such words, however, cannot fully encompass the experience of living with such a pain. In those with chronic pain after spinal cord injury it is frequently the pain rather than the paralysis that interferes with work and social life. One woman has said that paralysis does not stop life, but pain may. (2)

Mechanisms
There may be many mechanisms underlying phantom limb pain. Damage to nerve endings is often important: subsequent erroneous regrowth can lead to abnormal and painful discharge of neurons in the stump, and may change the way that nerves from the amputated limb connect to neurons within the spinal cord. There is also evidence for altered nervous activity within the brain as a result of the loss of sensory input from the amputated limb.

Unfortunately, phantom limb pain is generable intractable and chronic; once it develops it persists and is rarely improved by present medical treatments. Destructive surgical procedures are also of limited use. They can be effective for a few months, but pain always returns, frequently worse, and so surgery is only performed in patients with terminal illness.

New treatments
Recently, some potentially valuable treatments have arisen, based on new ways of perceiving the origin of the pain itself.

Flor's group has shown that the development of phantom limb pain is correlated with changes in the way peripheral areas of the body are represented in the sensory cortex. Although is not clear why this should lead to pain, they devised experiments to reverse this cortical plasticity to see whether pain sensations were also altered.

They found that use of an electrical prosthetic limb moved by signals from the patient's muscle reduced the pain if used for several hours per day. Brain imaging revealed that this effect was dependent on a reversion of the sensory cortex to its original state. (3) A task involving repeated touching of the skin over the stump, to improve sensory discrimination there, also reduced phantom limb pain, possibly by replacing some of the sensory input to the brain lost following amputation. (4)

Visual tricks
In his last book Patrick Wall suggested that pain might be considered a 'need state', like thirst, rather than simply a sensation. If so then the 'need' might involve movement to avoid or reduce pain. (5)

Evidence that stimulation of the motor cortex (the area that controls movement) can reduce phantom limb pain has been around for some time. (6) Perhaps more surprising was a trial by Ramachandran and Rogers-Ramachandran in 1996. (7) They asked people with amputations of the arm and phantom limb pain to place their arms inside a mirror box so that they saw their remaining arm mirror-reversed to look like their amputated one. When they moved their remaining arm in the box they were 'fooled' into thinking they were moving their amputated one, and their pain was reduced. Although this has proved less effective in some subsequent trials, it did suggest that phantom limb pain might reflect a loss of motor control to the limb, as well as loss of sensory input from it.

More recently the mirror box has been used with some success in pain that is not due to sensory loss. (8) In fact, a box may not be required. In phantom limb pain due to a peripheral nerve injury (brachial plexopathy), Giraux and Sirigu have shown that merely training patients to imagine their paralysed arms moving in relation to a moving arm on a screen in front of them can relieve phantom limb pain. (9)

They suggest that these attempts to link the visual and motor systems might be helping patients recreate a coherent body image, and so reduce pain as a result of reduced and disordered input. If this approach is successful, it may be that relatively simple treatments, such as patients imagining that they are swinging a golf club with their amputated limb, could have significant pain-relieving benefits.

Finally, in experiments still being developed, we are constructing an arm in virtual reality which subjects with phantom limb pain will move themselves using motion capture techniques. Movement of their stump will be captured by a movement-tracking device, and used to project the movement of the reconstituted limb in virtual reality. We anticipate that this will lead to a sense of re-embodiment in the virtual arm and hence to a reduction of the pain.

These new approaches are all based on a shift in
emphasis in phantom limb pain away from the site of damage 鈥?the stump 鈥?to the centre of pain processing: the brain. It appears that disordered inputs from the limb's sensory systems, combined with disrupted motor signal back to the limb, generate a mismatch between the brain's built-in map of the physical body and what is actually perceived. For some reason, this mismatch results in pain.

Whichever of these new techniques proves effective 鈥?and simple enough to be used 鈥?the prospects for relief from pain are probably brighter than at any time since Weir Mitchell first coined the term phantom limb pain in 1872.

Professor Jonathan Cole is a Consultant in Clinical Neurophysiology at Poole Hospital a professor at the University of Bournemouth, and Senior Lecturer in Clinical Neurosciences at the University of Southampton, UK. E-mail: jonathan@colefamily.org.uk



References
(1) Flor H (2002) Phantom limb pain: characteristics, causes and treatment. Lancet, 1, 182-189.

(2) Cole J (1994) Still Lives; narrative of spinal cord injury. Massachusetts: MIT Press.

(3) Lotze M, Flor H, Grodd W, Larbig W and Birmbaumer N (2001) Phantom movements and pain: an fMRI study in upper limb amputees. Brain, 124, 2268-2277.

(4) Flor H, Denke C, Schaefer M and Grusser M (2001) Sensory discrimination training alters both cortical reorganisation and phantom limb pain. Lancet, 357, 1763-1764.

(5) Wall P D (1999) Pain, the science of suffering. Weidenfeld and Nicolson.

(6) Garcia-Larrea R, Peyron R, Mertens P, Gregoire M C, Lavenne D, Le Bars P, Convers F, Mauguiere F, Sindou M and Laurent B (1999) Electrical stimulation of motor cortex for pain control: a combined PET scan and electrophysiological study. Pain, 83, 259-273.

(7) Ramachandran V S and Rogers-Ramachandran D (1996) Synaesthesia in phantom limbs induced with mirrors. Proc R Soc Lond B Biol Sci, 263, 377-286.

(8) McCabe C S, Haigh R C, Ring E F J, Halligan P W, Wall P D and Blake D R (2003) A controlled pilot study of the utility of mirror visual feedback in the treatment of complex regional pain syndrome (type 1). Rheumatology, 42, 97-101.

(9) Giraux P and Sirigu A (2003) Illusory movements of the paralysed limb restore motor cortex activity. Neuroimage, 20, S107-111.

you will find your answer here my friend

http://www.amputee-online.com/amputee/ph...

sensations after amputations

Phantom limb pain has been around as long as there have been amputees. Much research has been done on why phantom limb pain continues to be felt by some amputees for years. Pain "memories" and pain "gate" theories are among the most recent possible explanations, indicating that whole "body mapping" exists in the brain. Even when a piece of the body no longer exists, the "body map" remains intact and phantom sensation or pain can result when the brain sends ever more persistent messages to limbs not there.

Phantom sensation is the conscious sensation that the amputated limb is still there - these sensations usually decrease over time. Phantom limb pain is a conscious feeling of a painful limb, after the limb has been amputated. Phantom limb pain can range in type and intensity. For example, a mild form might be experienced as a sharp, intermittent stabbing pain causing the limb to jerk in reaction to the pain - an example of a more severe type might be the feeling that the missing limb is being crushed. Usually phantom limb pain diminishes in frequency and intensity over time. For a small number of amputees, however, phantom limb pain can become chronic and debilitating because of the frequency and severity of the pain.

Below are some of the remedies that have been tried by amputees. However, a remedy that works for one amputee may not work for another.

The techniques for alleviating phantom limb pain covered in this article have been gathered from many sources and some are anecdotal. Our aim is only to provide information on the many techniques available. You should discuss certain more complex techniques, which may be of interest to you, with your doctor or clinic team before applying them.

The War Amps accepts no liability for the interpretation and subsequent use of information found in this article.

Techniques for Dealing With Phantom Limb Pain
(Listed alphabetically)

Acupuncture
Anaesthetics
Biofeedback
Chiropractic
Cold
Cranial Sacral Therapy
Desensitization
Dietary and Herbal Supplements
Electrical Stimulation
Exercise
Farabloc
Heat
Keeping a Journal
LaKOTA

Magnetic Therapy
Massage
Medications
Meditation
Psychotherapy
Shrinker Socks
Wearing Your Artificial Limb


Acupuncture
Acupuncture is a healing art that has been practised in China for several thousand years to treat a variety of ailments, including chronic pain. Acupuncture involves the insertion of tiny needles into the skin at specific sites. The needle is then twirled for a few minutes or a low electrical current is applied. It is not fully understood how acupuncture works - the Chinese healing art stresses the energy flow of the Ch'i, or life force, while western medicine suggests it stimulates the production of the body's natural painkillers called endorphins.


Anaesthetics

Preoperative: Epidural Blockade
When amputation surgery is performed, whether caused by trauma or disease, the amputee is often in pain before the surgery commences. It is thought that this pain imprints on the brain and creates a "pain path" which then causes phantom limb pain after the limb is removed. By using an epidural, an injection of anaesthetic to the spine, usually for a period of 72 hours prior to the surgery, the message of pain is blocked from reaching the brain and creating a "pain path." It has been reported that people who have an epidural blockade prior to surgery experience less pain during the postoperative period, as well as a reduction in the frequency and severity of phantom limb pain. It is also thought that the epidural reduces pain by cutting off the pain messages associated with the surgery, which still register in the brain even though the patient is unconscious.


Postoperative: Local anaesthetic (examples: Lidocaine, Marcaine, Novocaine, Pontocaine, Xylocaine) These medications act on nerve cells by making them incapable of transmitting pain messages for a short period of time. They may be given as spinal (a small needle into the spinal column, in the lower back), epidural (a small needle and catheter into the spinal column, in the lower or mid-back), by local injection or a wide variety of nerve blocks. These may be used to relieve trigger points and reduce stump pain.


Biofeedback
Advocates of biofeedback feel that phantom pain may happen because of anxiety, which may increase muscle tension and contribute to the pain cycle. "Hyperactive muscles" cause irritation in the cut ends of the nerves in the residual limb. Electrodes are attached to the residual limb which detect when the muscle is tensed and trigger a flashing light or buzzer to provide feedback. Once the amputee has become aware of the muscle tension they learn to relax the muscle. When an appropriate decrease in muscle tension is reached the feedback stops. The focus of this treatment is to teach the muscle(s) how to relax, thereby relieving the pain.


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Chiropractic
Some amputees may find relief through chiropractic - which means "treatment by hand." Chiropractic does not involve drugs or surgery, but instead concentrates on the spine in relation to the total body. Doctors of chiropractic, or chiropractors, specialize in the understanding and treatment of the different parts of the spine: bone (vertebrae), muscles and nerves. When a vertebral joint is not working properly it can create an imbalance which disturbs the nervous system. This can lead to excess strain being placed on other joints, resulting in some form of pain. Through manual adjustment, or manipulation of the spine, chiropractic works to correct misalignments of the spine thus alleviating pain.


Cold
Applying cold to the residual limb may help alleviate some of the discomfort associated with phantom limb pain or muscle spasms. Refreshing coolness can be administered through cold compresses, ice packs or cool baths. Amputees may also wish to try a cooling cream or gel. One newer product available is Biofreeze, which is an analgesic cryotherapy gel made from the extract of a South American holly shrub. Biofreeze creates a cooling sensation within the skin that can last several hours. Another gel, Glenalgesic Blue, is a topical pain fighter for the prompt and temporary relief of muscular aches and pains, containing menthol, alcohol and camphor. [See also Heat.]


Cranial Sacral Therapy
This type of therapy, involving the study of bone and joint misalignment related to the head, has been practised by many different cultures for thousands of years. Therapeutic touch is applied to the head, and meditation and visualization techniques may also be used in conjunction with cranial sacral therapy. A therapist treating phantom pain may "massage" the missing limb, as well as encourage visualization of the lost limb in an effort to help amputees release any sense of grief, loss or anger towards the missing limb(s).


Desensitization
The nerves in the stump of the amputated limb can be very sensitive, especially directly following the amputation. Not only does desensitization reduce nerve sensitivity, it can also reduce pain and discomfort overall. Rubbing the stump with a piece of terry cloth, gently manipulating the stump manually, tapping the stump, or using a vibrator can all help to desensitize the nerves, alleviating sensation and pain. [See also Massage.]



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Dietary and Herbal Supplements
Some amputees have found certain dietary supplements or homeopathic food products help reduce phantom limb pain. Examples of dietary supplements amputees have tried include: potassium; calcium; magnesium, and injections of Vitamin B12. Certain herbal products have also been found useful by some amputees including juniper berries (interestingly called "ghost-berry" by Native Americans). Antioxidants such as Pycnogenol (a pine bark extract sold in Canada as a food product) and Grape Seed Extract are extremely concentrated bioflavonoids, which until 1936 were known as Vitamin P. Antioxidants attack free radicals, which are unstable atoms inside our bodies that attack all body tissues, degrade collagen and reprogram DNA. Free radicals are believed to be the underlying cause in many diseases. Antioxidants are found in high concentrations in grape seeds and pine bark, and in lesser amounts in grape skins, cranberries, lemon-tree bark and hazelnut-tree leaves. Antioxidants are available in liquid and pill form.

*Amputees should always consult their doctor before taking any supplements or herbs, as these are not harmless, but can have powerful side effects. They may also interfere or conflict with other medications being taken at the same time.


Electrical Stimulation
Another theory behind phantom limb pain suggests that it occurs because the nerves in the residual limb lack the stimulus once provided by the missing limb. Transcutaneous electrical nerve stimulation (TENS) and microcurrent electrical therapy (MET with the product Alpha-Stim 100) are two examples of electrical treatment using low current at a low-frequency oscillation to stimulate the nerves and provide pain relief. Depending on the severity of pain, the battery operated devices can be used for 10-20 minutes and upwards (recommended times and demonstration of how to use one of these devices may be provided by a medical professional). As TENS can cause arrhythmia it should not be used by people with heart disease and neither TENS nor MET should be used by individuals with pacemakers.


Exercise
Exercise increases circulation and stimulates the production of endorphins (chemicals naturally produced in the brain that kill pain). Many amputees find that moderate and frequent exercise can help to reduce phantom pain. Flexing and relaxing the muscles on the residual limb also helps some amputees.



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Farabloc
Farabloc is a fabric which contains extremely thin steel threads but looks and feels like linen. The makers state that Farabloc has a shielding effect from ions and magnetic influences, which protects damaged nerve endings. It stimulates blood circulation and produces a pleasant feeling of warmth. It can be cut and sewn, washed and ironed like any other fabric, and is available in blanket forms of various sizes. People may have socks, sheaths, or custom residual limb covers made from Farabloc or the material may be incorporated directly into a prosthetic socket.


Heat
Applying soothing warmth has been reported to help deal with occasional bouts of phantom limb pain. Warm baths, a heating pack, a Magic Bag, or wrapping the stump in warm, soft fabric to increase circulation are all examples of how heat can be used. There are also rubs and gels which generate heat, such as Rub A535 or Tiger Balm. More advanced forms of heat therapy can be used under the guidance of a trained professional. Some amputees alternate between applying heat and cold. [See also Cold.]


Keeping a Journal
Some amputees write down dates and times as well as other factors that may be present when they experience phantom limb pain, such as stress. A record kept over time may indicate factors that influence or trigger the occurrence, frequency or severity of an attack of phantom limb pain in the same way that migraine sufferers have found that certain foods trigger their migraines.


LaKOTA

This is a natural medication available over-the-counter. It is a herbal analgesic developed for arthritis and other muscle and joint pains, and some of our members are reporting relief from phantom limb pain with it. It comes in a roll on applicator or tablet form.



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Magnetic Therapy
Magnets have been used for thousands of years to treat many conditions, including recently phantom limb pain. Magnetic therapy involves applying a magnetic field to the body to relieve pain and speed up the healing process. The application of electromagnetic fields has been shown to affect cell permeability and improve oxygen delivery to the cells, which can lead to better absorption of nutrients, improved circulation, and clearance of waste products. Magnets may also reduce inflammation and pain, and promote healing. The magnets are usually incorporated into bracelets, belts, or fabric straps, and are available in differing strengths and sizes. These products are available from several companies such as Nikken and Bioflow. (It is recommended that you consult your doctor before trying magnetic therapy to ensure it is a good choice for you.)


Massage
Massaging your limb is a good way to increase blood-flow and circulation, which may help to alleviate some discomfort. Massage may also help to reduce swelling and loosen stiff muscles, which can provide some relief from pain.


Medications
Medications are useful in the treatment of pain (especially chronic pain). However, many amputees prefer to try other avenues of relief first. It is important for the amputee to understand all the possible side-effects of over-the-counter and prescription medications, including the implications of long-term use.


Anti-Inflammatory Drugs (examples: acetaminophen [Tylenol], aspirin, ibuprofen [Advil, Motrin]
Acetaminophen are all examples of medication which can reduce mild swelling or soreness, and are useful for mild to moderate pain. They are non-addictive and may be effective for occasional bouts of phantom pain. One amputee uses Tylenol Arthritis Pain for relief from his phantom limb pain.


Antidepressants (examples: Amitriptyline, Elavil, Pamelor, Paxil, Prozac, Zoloft)


Developed to treat depression, many antidepressants have been found to be useful in the treatment of many chronic pain conditions, including phantom limb pain. These drugs work centrally on the brain to either block or increase certain chemicals that help regulate normal brain function.


Anticonvulsants or anti-seizure medications (examples: Tegratol, Neurontin)
These drugs have also been found useful in the treatment of phantom limb pain. They act directly on the nerves both in the residual limb and in the brain to alter neurotransmission, thus calming nerves in the residual limb which may have become over-active following amputation. These drugs are prescribed in small doses and are gradually increased to a level which promotes relief. It is also very important to decrease the dose gradually before ceasing to take the medication.


Narcotics (examples: Codeine, Demerol, Morphine, Percodan, Percocet)
These drugs mimic the pain killing chemicals released by the brain in response to pain. While they are very effective as temporary solutions for pain after surgery, trauma, or to treat cancer pain, they are highly addictive and in the majority of cases should not be used for a prolonged period. Amputees who have only an occasional severe attack of phantom pain may benefit from a limited course of this type of drug. When these drugs are taken on a regular basis the patient becomes addicted and desensitized to the drugs, requiring more of the drugs while achieving less effective pain relief.



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Meditation
Both physical and mental tension can make pain worse. Meditation may help to reduce phantom limb pain by relaxing tense muscles and lowering anxiety levels. The aim of meditation is to produce a state of relaxed but alert awareness, this is sometimes combined with vizualisation exercises that encourage people to think of pain as something remote and separate from themselves.


Psychotherapy
Some amputees may find individual or group therapy beneficial. Some have even tried hypnosis. Trained professionals can help amputees learn coping skills and can provide psychological and emotional support for dealing with pain.


Shrinker Socks
Bandaging and shrinker socks apply even pressure to the residual limb which may help to reduce or alleviate phantom limb pain.


Wearing Your Artificial Limb
As well as improving circulation, putting on your artificial limb and moving around may also help alleviate phantom limb pain.