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One approach that has received public interest is the use of a mirror box. The mirror box provides a reflection of the intact hand or limb that allows the patient to "move" the phantom limb, and to unclench it from potentially painful positions.
As of 2011, however, the quality of evidence is low. There is a wide range in the effectiveness of this approach. The potential for a person to benefit from mirror therapy is not predictable and appears to be related to the subjective ability of the patient to internalize the reflection of a complete limb as their own limb. About 40% of people do not benefit from mirror therapy.
Most approaches to treatment over the past two decades have not shown consistent symptom improvement. Treatment approaches have included medication such as antidepressants, spinal cord stimulation, vibration therapy, acupuncture, hypnosis, and biofeedback. Reliable evidence is lacking on whether any treatment is more effective than the others.
Most treatments are not very effective. Ketamine or morphine may be useful around the time of surgery. Morphine may be helpful for longer periods of time. Evidence for gabapentin is mixed. Perineural catheters that provide local anesthetic agents have poor evidence when placed after surgery in an effort to prevent phantom limb pain.
Various methods have been used to treat phantom limb pain. Doctors may prescribe medications to reduce the pain. Some antidepressants or antiepileptics have been shown to have a beneficial effect on reducing phantom limb pain. Often physical methods such as light massage, electrical stimulation, and hot and cold therapy have been used with variable results.
There are many different treatment options for phantom limb pain that are actively being researched. Most treatments do not take into account the mechanisms underlying phantom pains, and are therefore ineffective. However, there are a few treatment options that have been shown to alleviate pain in some patients, but these treatment options usually have a success rate less than 30%. It is important to note that this rate of success does not exceed the placebo effect. It is also important to note that because the degree of cortical reorganization is proportional to phantom limb pains, any perturbations to the amputated regions may increase pain perception.
Deep brain stimulation is a surgical technique used to alleviate patients from phantom limb pain. Prior to surgery, patients undergo functional brain imaging techniques such as PET scans and functional MRI to determine an appropriate trajectory of where pain is originating. Surgery is then carried out under local anesthetic, because patient feedback during the operation is needed. In the study conducted by Bittar et al., a radiofrequency electrode with four contact points was placed on the brain. Once the electrode was in place, the contact locations were altered slightly according to where the patient felt the greatest relief from pain. Once the location of maximal relief was determined, the electrode was implanted and secured to the skull. After the primary surgery, a secondary surgery under general anesthesia was conducted. A subcutaneous pulse generator was implanted into a pectoral pocket below the clavicle to stimulate the electrode. It was found that all three patients studied had gained satisfactory pain relief from the deep brain stimulation. Pain had not been completely eliminated, but the intensity had been reduced by over 50% and the burning component had completely vanished.
Electromyography (EMG) and Nerve Conduction Studies (NCS) are important ancillary tests in CRPS because they are among the most reliable methods of detecting nerve injury. They can be used as one of the primary methods to distinguish between CRPS I & II, which differ based on whether there is evidence of actual nerve damage. EMG & NCS are also among the best tests for ruling in or out alternative diagnoses. CRPS is a "diagnosis of exclusion", which requires that there be no other diagnosis that can explain the patient's symptoms. This is very important to emphasise because otherwise patients can be given a wrong diagnosis of CRPS when they actually have a treatable condition that better accounts for their symptoms. An example is severe Carpal Tunnel Syndrome, which can often present in a very similar way to CRPS. Unlike CRPS, Carpal Tunnel Syndrome can often be corrected with surgery in order to alleviate the pain and avoid permanent nerve damage and malformation.
Both EMG and NCS involve some measure of discomfort. EMG involves the use of a tiny needle that is inserted into specific muscles to test the associated muscle and nerve function. Both EMG & NCS involve very mild shocks that in normal patients are comparable to a rubber band snapping on the skin. Although these tests can be very useful in CRPS, thorough informed consent needs to be obtained prior to the procedure, particularly in patients experiencing severe allodynia. In spite of the utility of the test, these patients may wish to decline the procedure in order to avoid discomfort.
There is little research on treatment for phantom vibrations. Carrying the cell phone in a different position reduces phantom vibrations for some people. Other methods include turning off the vibrate mode or using a different device.
Presently, established empirical evidence suggests against thermography's efficacy as a reliable tool for diagnosing CRPS. Although CRPS may, in some cases, lead to measurably altered blood flow throughout an affected region, many other factors can also contribute to an altered thermographic reading, including the patient's smoking habits, use of certain skin lotions, recent physical activity, and prior history of trauma to the region. Also, not all patients diagnosed with CRPS demonstrate such "vasomotor instability" — less often, still, those in the later stages of the disease. Thus, thermography alone cannot be used as conclusive evidence for - or against - a diagnosis of CRPS and must be interpreted in light of the patient's larger medical history and prior diagnostic studies.
In order to minimise the confounding influence of external factors, patients undergoing infrared thermographic testing must conform to special restrictions regarding the use of certain vasoconstrictors (namely, nicotine and caffeine), skin lotions, physical therapy, and other diagnostic procedures in the days prior to testing. Patients may also be required to discontinue certain pain medications and sympathetic blockers. After a patient arrives at a thermographic laboratory, he or she is allowed to reach thermal equilibrium in a 16–20 °C, draft-free, steady-state room wearing a loose fitting cotton hospital gown for approximately twenty minutes. A technician then takes infrared images of both the patient's affected and unaffected limbs, as well as reference images of other parts of the patient's body, including his or her face, upper back, and lower back. After capturing a set of baseline images, some labs further require the patient to undergo cold-water autonomic-functional-stress-testing to evaluate the function of his or her autonomic nervous system's peripheral vasoconstrictor reflex. This is performed by placing a patient's unaffected limb in a cold water bath (approximately 20 °C) for five minutes while collecting images. In a normal, intact, functioning autonomic nervous system, a patient's affected extremity will become colder. Conversely, warming of an affected extremity may indicate a disruption of the body's normal thermoregulatory vasoconstrictor function, which may sometimes indicate underlying CRPS.
Daily oral muscle physical therapy, or the administration of antidepressants have been reported as effective therapy for occlusal dysesthesia patients. Tooth grinding, and the replacement or removal of all dental work should be avoided in patients with occlusal dysesthesia, despite the frequent requests for further surgery often made by these patients.
Antidepressants are also often prescribed for scalp dysesthesia.
Prakash et al. found that many patients suffering from burning mouth syndrome (BMS), one variant of occlusal dysesthesia, also report painful sensations in other parts of the body. Many of the patients suffering from BMS met the classification of restless leg syndrome (RLS). About half of these patients also had a family history of RLS. These results suggest that some BMS symptoms may be caused by the same pathway as RLS in some patients, indicating that dopaminergic drugs regularly used to treat RLS may be effective in treating BMS as well.
A patient suffering from dysesthesia can find it to be unbearable at times. Dysesthetic burning has been called "Dante-esque" pain. The terminology used to describe it is usually interchangeable with descriptions of Hell in classic literature. It is the "bluntest" pain of which the human body is capable, and is characterized by the absence of accurate discriminative information.
Temperature change and heat both affect the sensation and raise the level of the steady pain. This pain upgrades with tonic light touch, phasic rubbing, or rough textures to become evoked pain.
The patient often cannot endure the touch of clothing. His or her entire life becomes an exercise in avoiding evoked pain. It causes difficulty in obtaining rest because bed-clothing contacts the skin. It drives the patient to a hysterical search for relief of the pain, which ends in some degree of resignation and frequent depression. Patients indicate that it has robbed them of their identity, since their values and mental priorities are so consumed by its avoidance.
Chronic anxiety is often associated with dysesthesia. Patients suffering from this anxiety may experience numbness or tingling in the face. In one study, those patients that were examined psychologically had symptoms of anxiety, depression, obsessive-compulsive personality disorder, or somatoform disorder.
In most studies, a majority of cell phone users report experiencing occasional phantom vibrations or ringing, with reported rates ranging from 27.4% to 89%. Once every two weeks is a typical frequency for the sensations, though a minority experience them daily. Most people are not seriously bothered by the sensations.
Supernumerary phantom limb is a condition where the affected individual believes and receives sensory information from limbs of the body that do not actually exist, and never have existed, in contradistinction to phantom limbs, which appear after an individual has had a limb removed from the body and still receives input from it.
An fMRI study of a subject with a supernumerary phantom left arm was done by Khateb "et al." at the Laboratory of Experimental Neuropsychology at the University of Geneva. When the subject was told to touch her right cheek with the phantom limb, there was increased activity in the motor cortex of her brain in the area roughly corresponding to the left arm. When she announced that she had touched the phantom limb to her cheek, activity was monitored in the area of the somatosensory cortex that corresponded to the right cheek. At times during the experiment, the subject was asked to move the phantom limb to a location that was obstructed or otherwise unfeasible. In these instances, there was similar activation of the motor cortex but no such activity in the somatosensory cortex.
For most cases the diagnosis for congenital amputation is not made until the infant is born. One procedure that is helpful in determining this condition in an infant is an ultrasound examination of a fetus when still in the mother's abdomen as it can reveal the absence of a limb. However, since ultrasounds are routine they may not pick up all the signs of some of the more subtle birth defects.
The most popular method of treatment for congenital amputation is having the child be fit for a prosthesis which can lead to normal development, so the muscles don't atrophy. If there is congenital amputation of the fingers, plastic surgery can be performed by using the big toe or second toes in place of the missing fingers of the hand.
In rare cases of amniotic banding syndrome, if diagnosed "in utero", fetal surgery may be considered to save a limb which is in danger of amputation.
Studies suggest that prenatal care for mothers during their pregnancies can prevent congenital amputation. Knowing environmental and genetic risks is also important. Heavy exposure to chemicals, smoking, alcohol, poor diet, or engaging in any other teratogenic activities while pregnant can increase the risk of having a child born with a congenital amputation. Folic acid is a multivitamin that has been found to reduce birth defects.
Erythromelalgia is a difficult condition to diagnose as there are no specific tests available. However, reduced capillary density has been observed microscopically during flaring; and reduced capillary perfusion is noted in the patient. Another test that can be done is to have the patient elevate their legs, and note the reversal (from red to pale) in skin color. Tests done at universities include quantitative sensory nerve testing, laser evoked potentials, sweat testing and epidermal sensory nerve fiber density test (which is an objective test for small fiber sensory neuropathy). Due the aforementioned factors, patients may face delays in diagnosis.
Once it has been established that it is not secondary erythromelalgia — see below — a programme of management can be put in place.
Some diseases present with symptoms similar to erythromelalgia. Complex regional pain syndrome (CRPS), for instance, presents with severe burning pain and redness except these symptoms are often unilateral (versus symmetric) and may be proximal instead of purely or primarily distal. Furthermore, attacks triggered by heat and resolved by cooling are less common with CRPS.
Erythromelalgia is sometimes caused by other disorders. A partial list of diseases known to precipitate erythromelalgia is below.
Of people that have a sympathectomy, it is impossible to predict who will end up with a more severe version of this disorder, as there is no link to gender, age or weight. There is no test or screening process that would enable doctors to predict who is more susceptible.
One form of treatment that has produced a more integrated body awareness is mirror therapy, in which the individual who denies that the affected limb belongs to their body looks into a mirror at the limb. Patients looking into the mirror state that the limb does belong to them; however body ownership of the limb does not remain after the mirror is taken away.
Obdormition (; from Latin "obdormire" "to fall asleep") is a medical term describing numbness in a limb, often caused by constant pressure on nerves or lack of movement. This is colloquially referred to as the limb "going to sleep," and usually followed by paresthesia, colloquially called "pins and needles".
Percutaneous electrical nerve stimulation, or PENS, is used mainly in the treatment of intractable pain associated with chronic low back pain syndrome, cancer, and other disorders. It is a technique involving insertion of an ultra-fine acupuncture needle which probes into the soft tissues or muscles to electrically stimulate nerve fibers in the sclerotomal, myotomal, or dermatomal distribution corresponding to the patient's pain symptoms. PENS is related to both electroacupuncture and transcutaneous electrical nerve stimulation.
Electroanalgesia poses serious health problems in those patients who need other electrical equipment in their bodies, such as pacemakers and hearing aids, because the electrical signals of the multiple devices can interfere with each other and fail. People with heart problems, such as irregular heartbeat, are also at risk because the devices can throw off the normal electrical signal of the heart.
For secondary erythromelalgia, treatment of the underlying primary disorder is the most primary method of treatment. Although aspirin has been thought to reduce symptoms of erythromelalgia, it is rare to find evidence that this is effective. Mechanical cooling of the limbs by elevating them can help or managing the ambient environment frequently is often necessary constantly as flares occur due to sympathetic autonomic dysfunction of the capillaries. The pain that accompanies it is severe and treated separately (the pain is similar to CRPS, phantom limb or thalamic pain syndrome). Patients are strongly advised "not" to place the affected limbs in cold water to relieve symptoms when flaring occurs. It may seem a good idea, but it precipitates problems further down the line causing damage to the skin and ulceration often intractable due to the damaged skin. A possible reduction in skin damage may be accomplished by enclosing the flaring limb in a commonly available, thin, heat transparent, water impermeable, plastic food storage bag. The advice of a physician is advised depending on specific circumstances.
Primary erythromelalgia management is symptomatic, i.e. treating painful symptoms only. Specific management tactics include avoidance of attack triggers such as: heat, change in temperature, exercise or over exertion, alcohol and spicy foods. This list is by no means comprehensive as there are many triggers to set off a 'flaring' episode that are inexplicable. Whilst a cool environment is helpful in keeping the symptoms in control, the use of cold water baths is strongly discouraged. In pursuit of added relief sufferers can inadvertently cause tissue damage or death, i.e. necrosis. See comments at the end of the preceding paragraph regarding possible effectiveness of plastic food storage bags to avoid/reduce negative effects of submersion in cold water baths.
One clinical study has demonstrated the efficacy of IV lidocaine or oral mexilitine, though it should be noted that differences between the primary and secondary forms were not studied. Another trial has shown promise for misoprostol, while other have shown that gabapentin, venlafaxine and oral magnesium may also be effective, but no further testing was carried out as newer research superseded this combination.
Strong anecdotal evidence from EM patients shows that a combination of drugs such as duloxetine and pregabalin is an effective way of reducing the stabbing pains and burning sensation symptoms of erythromelalgia in conjunction with the appropriate analgesia. In some cases, antihistamines may give some relief. Most people with erythromelalgia never go into remission and the symptoms are ever present at some level, whilst others get worse, or the EM is eventually a symptom of another disease such as systemic scleroderma.
Some suffering with EM are prescribed ketamine topical creams as a way of managing pain on a long term basis. Feedback from some EM patients has led to reduction in usage as they believe it is only effective for short periods.
Living with erythromelalgia can result in a deterioration in quality of life resulting in the inability to function in a work place, lack of mobility, depression, and is socially alienating; much greater education of medical practitioners is needed. As with many rare diseases, many people with EM end up taking years to get a diagnosis and to receive appropriate treatment.
Research into the genetic mutations continues but there is a paucity of clinical studies focusing on living with erythromelalgia. There is much urgency within pharmaceutical companies to provide a solution to those who suffer with pain such as that with erythromelalgia.
Somatoparaphrenia is a type of monothematic delusion where one denies ownership of a limb or an entire side of one's body. Even if provided with undeniable proof that the limb belongs to and is attached to their own body, the patient produces elaborate confabulations about whose limb it really is, or how the limb ended up on their body. In some cases, delusions become so elaborate that a limb may be treated and cared for as if it were a separate being.
Somatoparaphrenia differs from a similar disorder, asomatognosia, which is characterized as loss of recognition of half of the body or a limb, possibly due to paralysis or unilateral neglect. For example, asomatognosic patients may mistake their arm for the doctor's. However, they can be shown their limb and this error is temporarily corrected.
Somatoparaphrenia has been reported to occur predominately in the left arm of one's body, and it is often accompanied by left-sided paralysis and anosognosia (denial or lack of awareness) of the paralysis. The link between somatoparaphrenia and paralysis has been documented in many clinical cases and while the question arises as to whether paralysis is necessary for somatoparaphrenia to occur, anosognosia is not, as documented by cases with somatoparaphrenia and paralysis with no anosognosia.
Functional magnetic resonance imaging brain scanning has been used to measure pain, and correlates well with self-reported pain.
Compensatory hyperhidrosis is a form of neuropathy. It is encountered in patients with myelopathy, thoracic disease, cerebrovascular disease, nerve trauma or after surgeries. The exact mechanism of the phenomenon is poorly understood. It is attributed to the perception in the hypothalamus (brain) that the body temperature is too high. The sweating is induced to reduce body heat.
Excessive sweating due to nervousness, anger, previous trauma or fear is called hyperhidrosis.
Compensatory hyperhidrosis is the most common side effect of endoscopic thoracic sympathectomy, a surgery to treat severe focal hyperhidrosis, often affecting just one part of the body. It may also be called "rebound" or "reflex hyperhidrosis". In a small number of individuals, compensatory hyperhidrosis following sympathectomy is disruptive, because afflicted individuals may have to change sweat-soaked clothing two or three times a day.
According to Dr Hooshmand, sympathectomy permanently damages the temperature regulatory system. The permanent destruction of thermoregulatory function of the sympathetic nervous system causes latent complications, e.g., RSD in contralateral extremity.
Following surgery for axillary (armpit), palmar (palm) hyperhidrosis (see focal hyperhidrosis) and blushing, the body may sweat excessively at untreated areas, most commonly the lower back and trunk, but can be spread over the total body surface below the level of the cut. The upper part of the body, above the sympathetic chain transection, the body becomes anhidriotic, where the patient is unable to sweat or cool down, which further compromises the body's thermoregulation and can lead to elevated core temperature, overheating and hyperthermia. Below the level of the sympathetic chain interruption, body temperature is significantly lower, creating a stark contrast that can be observed on thermal images. The difference in temperatures between the sympathetically under- and overactive regions can be as high as 10 Celsius.
No surgical outcomes studies exist for evaluating the function of the thumbs after an on-top plasty reconstruction.
Mirror-touch synesthesia is a rare condition which causes individuals to experience the same sensation (such as touch) that another person feels. For example, if someone with this condition were to observe someone touching their cheek, they would feel the same sensation on their own cheek. Synesthesia, in general, is described as a condition in which a stimulus causes an individual to experience an additional sensation. Synesthesia is usually a developmental condition; however, recent research has shown that mirror touch synesthesia can be acquired after sensory loss following amputation.