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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.
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.
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.
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.
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.
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.
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.
Evaluation of any suspected disease of the somatosensory system is included in a neurological examination of the peripheral nervous system. Modern techniques for testing somatosensory function are still quite crude compared to testing motor function. Evaluation of somatosensory stimuli are limited by the patient's interpretation of sensation in response to testing.
Tactile sensation is tested with a cotton wisp or light touch with a finger. Pain is assessed by pinprick or pinwheel (Wartenberg wheel). A 128 Hz tuning fork is used for testing vibrations.
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.
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".
Patients may experience numbness, prickling or tingling sensations (paresthesias), or the feeling a limb has "fallen asleep" (an indicator of nerve compression), burning, cutting or other sensations.
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.
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.
There is no cure for MMA. Treatment consists of muscle strengthening exercises and training in hand coordination. It has been proposed that the changes in this disease are from compression of the spinal cord in flexion due to forward shifting of the posterior dural sac. There have been treatments studies ranging from use of a cervical collar to anterior cervical fusion and posterior decompression.
MMA mostly occurs in males between the ages of 15 and 25. Onset and progression are slow. MMA is seen most frequently in Asia, particularly in Japan and India; it is much less common in North America.
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.
Hemiplegia is identified by clinical examination by a health professional, such as a physiotherapist or doctor. Radiological studies like a CT scan or magnetic resonance imaging of the brain should be used to confirm injury in the brain and spinal cord, but alone cannot be used to identify movement disorders. Individuals who develop seizures may undergo tests to determine where the focus of excess electrical activity is.
Hemiplegia patients usually show a characteristic gait. The leg on the affected side is extended and internally rotated and is swung in a wide, lateral arc rather than lifted in order to move it forward. The upper limb on the same side is also adducted at the shoulder, flexed at the elbow, and pronated at the wrist with the thumb tucked into the palm and the fingers curled around it.
There are a variety of standardized assessment scales available to physiotherapists and other health care professionals for use in the ongoing evaluation of the status of a patient’s hemiplegia. The use of standardized assessment scales may help physiotherapists and other health care professionals during the course of their treatment plant to:
- Prioritize treatment interventions based on specific identifiable motor and sensory deficits
- Create appropriate short- and long-term goals for treatment based on the outcome of the scales, their professional expertise and the desires of the patient
- Evaluate the potential burden of care and monitor any changes based on either improving or declining scores
Some of the most commonly used scales in the assessment of hemiplegia are:
- The Fugl-Meyer Assessment of Physical Performance (FMA)
The FMA is often used as a measure of functional or physical impairment following a cerebrovascular accident (CVA). It measures sensory and motor impairment of the upper and lower extremities, balance in several positions, range of motion, and pain. This test is a reliable and valid measure in measuring post-stroke impairments related to stroke recovery. A lower score in each component of the test indicates higher impairment and a lower functional level for that area. The maximum score for each component is 66 for the upper extremities, 34 for the lower extremities, and 14 for balance. Administration of the FMA should be done after reviewing a training manual.
- The Chedoke-McMaster Stroke Assessment (CMSA)
This test is a reliable measure of two separate components evaluating both motor impairment and disability. The disability component assesses any changes in physical function including gross motor function and walking ability. The disability inventory can have a maximum score of 100 with 70 from the gross motor index and 30 from the walking index. Each task in this inventory has a maximum score of seven except for the 2 minute walk test which is out of two. The impairment component of the test evaluates the upper and lower extremities, postural control and pain. The impairment inventory focuses on the seven stages of recovery from stroke from flaccid paralysis to normal motor functioning. A training workshop is recommended if the measure is being utilized for the purpose of data collection.
- The Stroke Rehabilitation Assessment of Movement (STREAM)
The STREAM consists of 30 test items involving upper-limb movements, lower-limb movements, and basic mobility items. It is a clinical measure of voluntary movements and general mobility (rolling, bridging, sit-to-stand, standing, stepping, walking and stairs) following a stroke. The voluntary movement part of the assessment is measured using a 3-point ordinal scale (unable to perform, partial performance, and complete performance) and the mobility part of the assessment uses a 4-point ordinal scale (unable, partial, complete with aid, complete no aid). The maximum score one can receive on the STREAM is a 70 (20 for each limb score and 30 for mobility score). The higher the score, the better movement and mobility is available for the individual being scored.
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.
Computed tomography (CT) is an imaging modality that produces a 3-dimensional radiograph. A series of plain radiographs are taken in a spiral around the site of interest, and the individual 2-D radiographs are converted into a 3-D image by a computer. The image may be manipulated to view in different planes, such as cross-section, making it possible to see an injury from multiple perspectives and improving diagnostic capabilities when compared to plain radiographs. Like plain radiographs, CT is not as useful for soft tissue lesions when compared to boney lesions. However, CT requires general anesthesia, and is more costly and less available than plain radiographs, limiting its use in general practice. CT provides a large amount of data with exceptional speed, taking only seconds to minutes to complete. When compared to MRI, it is not only significantly faster (MRI takes 1–2 hours to produce an image), but also less expensive. Its combination of speed and imaging capabilities makes it beneficial for use prior to orthopedic surgery, especially in the case of complicated fractures, as it allows for visualization from all sides so that the surgeon may determine the best approach and method of correction prior to cutting. Upon completion of the CT, the horse may be rolled straight into the surgery suite for immediate surgical treatment.
Magnetic Resonance Imaging (MRI) produces a 3-dimensional image that allows for exceptional evaluation of soft tissue structures, as well as the detection of boney change and the presence of excessive fluid accumulation associated with inflammation. Like CT, an MRI image may be viewed in various planes of orientation, improving visualization of anatomic structures and any associated pathologic change. MRI is considered the gold standard for diagnosing soft tissue injury within the foot. While it can provide a definitive diagnosis in cases where other imaging modalities have failed, it does have several limitations. Available magnet size restricts imaging to the level of the stifle or elbow, or below. MRI takes a significant amount of time acquire an image, which translates to long anesthesia times and therefore reduces the size of the area that may be imaged in a single session. The area thought to be associated with lameness must be placed in the MRI. MRI is therefore inappropriate for any lameness that can not be localized to a specific region of the limb. Additionally, MRI has limited availability and high cost compared to the other imaging modalities.
Horses may undergo standing MRI, where the horse is sedated and imaged with a low-field magnet (0.27 Tesla), or it may be placed in a high-field magnet (1.5 or 3 Tesla) while under general anesthesia. Low-field magnets produce less resolution and the subtle swaying of the standing horse leads to motion artifact (blurring of the image), especially in the case of the knee or hock, leading to reduced image quality. However, standing MRI tends to be cheaper, and it eliminates the risks of general anesthesia, such as further damage to the injured area or additional injury that may occur during anesthetic recovery.
Gluteal gait is an abnormal gait caused by neurological problems. If the superior gluteal nerve or obturator nerves are injured, they fail to control the gluteus minimus and medius muscles properly, thus producing an inability to tilt the pelvis upward while swinging the leg forward to walk. To compensate for this loss, the leg swings out laterally so that the foot can move forward, producing a shuffling or waddling gait.
Injury to the superior gluteal nerve results in a characteristic motor loss, resulting in a disabling gluteus medius limp, to compensate for weakened abduction of the thigh by the gluteus medius and minimus, and/or a gluteal gait, a compensatory list of the body to the weakened gluteal side.
As a result of this compensation, the center of gravity is placed over the supporting lower limb. Medial rotation of the thigh is also severely impaired. When a person is asked to stand on one leg, the gluteus medius and minimus normally contract as soon as the contralateral foot leaves the floor, preventing tipping of the pelvis to the unsupported side. When a person with paralysis of the superior gluteal nerve is asked to stand on one leg, the pelvis descends on the unsupported side, indicating that the gluteus medius on the contralateral side is weak or non-functional. This observation is referred to clinically as a positive Trendelenburg's sign.
When the pelvis descends on the unsupported side, the lower limb becomes, in effect, too long and does not clear the ground when the foot is brought forward in the swing phase of walking. To compensate, the individual leans away from the unsupported side, raising the pelvis to allow adequate room for the foot to clear the ground as it swings forward.
Pseudoathetosis is abnormal writhing movements, usually of the fingers, caused by a failure of joint position sense (proprioception) and indicates disruption of the proprioceptive pathway, from nerve to parietal cortex.
Most children with symbrachydactyly have excellent function in daily activities. Due to the length of their arm, they do not qualify for most artificial limbs. However, some adaptive prosthetics and equipment for sports and leisure activities may be helpful when the child is older. Children who demonstrate some functional movement in their remaining fingers and within the palm are evaluated for possible surgery such as toe transfers.