Phantom Limb Pain

THE CLINICAL SYNDROME

Almost all patients who undergo amputation experience the sensation that the absent body part is still present. This sensation is often painful and quite distressing to the patient. The genesis of this phenomenon is not fully understood, but it is thought to be mediated in large part at the spinal cord level. Congenitally absent limbs do not seem to be subject to the same phenomenon. Patients with phantom limb pain will often describe the limb in vivid detail, albeit with the limb distorted or in abnormal position. In many patients, the sensation of a phantom limb will fade with time, but in some, phantom pain remains a distressing part of their daily life. The pain of phantom limb pain is often described as a constant unpleasant, dysesthetic pain that may be exacerbated by movement or stimulation of the affected cutaneous regions. There may be sharp, shooting neuritic pain superimposed on the constant dysesthetic symptoms. Some patients suffering from phantom limb pain will also note a burning component reminiscent of reflex sympathetic dystrophy. Some investigators report that severe limb pain before amputation increases the incidence of phantom limb pain, but other investigators have failed to prove this correlation.

SIGNS AND SYMPTOMS

The phantom limb pain may take multiple forms. It mot often takes the form of dysesthetic pain. Additionally, the patient with phantom limb pain may experience abnormal kinesthetic sensation (i.e., the limb is in an abnormal position). The patient may also experiences abnormal position). The patient may also experience abnormal kinetic sensation (i.e., feeling that the phantom limb is moving). It has been reported that many patients with phantom limb pain experience a telescoping phenomenon, in which the proximal thigh. Phantom limb pain may fade over time, with younger patients more likely to experience a diminution of phantom limb symptomatology. Due to the unusual nature of phantom limb sensation and pain, a behavioral component to the pain is invariably present.

Phanton limb pain is present in varying degrees of intensity in almost all patients who undergo amputation of a body part.

TREATMENT

The first step for all clinicians caring for patients with phantom limb pain is to reassure the patient that phantom sensations and/or pain after the loss of a limb is normal and that these sensations are real, not imagined. This alone will often reduce the anxiety and suffering of the patient. It is the consensus of most pain specialists that the earlier in the natural course of a painful disease that may lead to amputation, such as peripheral vascular insufficiency, that treatment is initiated, the less likely it is that the patient will develop phantom limb pain. In fact, many pain specialists recommend preemptive analgesia if the viability of a limb is in doubt before surgical amputation whenever possible. The following treatments have been shown to be useful in the palliation of phantom limb pain.

Adjuvant Analgesics

The anticonvulsant gabapentin represents a first line treatment in the palliation of phantom limb pain. Treatment with gabapentin should begin early in the course of the disease, and this drug may be used concurrently with neural blockade, opioid analgesics, and other adjuvant analgesics, including the antidepressant compounds, if care is taken to avoid central nervous system side effects. Carbamazepine should be considered in patients suffering from severe neuritic pain who have not responded to nerve blocks and gabapentin.

Antidepressants

Antidepressant compounds may also be useful adjuncts in the initial treatment of the patient suffering form phantom limb pain. On an acute basis, these drugs will help alleviate the significant sleep disturbance that is commonly seen in this setting. In addition, the antidepressants may be valuable in helping ameliorate the neuritic component of the pain, which is treated less effectively with narcotic analgesics. After several weeks of treatment, the antidepressants may exert a mood-elevating effect that may be desirable in some patients.

Nerve Blocks

Sympathetic neural blockade with local anesthetic and steroid via either epidural nerve block or blockade of the sympathetic nerves subserving the painful area appears to be a reasonable next step if the aforementioned pharmacologic modalities fail too control the pain of phantom limb pain. The exact mechanism of pain relief from neural blockade in the treatment of phantom limb pain is unknown, but it may be related to modulation of pain transmission at the spinal cord level. In general, neurodestructive procedures have a very low success rate and should be used only after all other treatments have been optimized, if at all.

Adjunctive Treatments

The application of ice packs to the area affected with phantom limb pain may provide relief in some patients. The application of heat will increase pain in most patients, presumably because of increased conduction of small fibers, but it is beneficial in an occasional patient and may be worth trying if the application of cold is ineffective. Transcutaneous electrical nerve stimulation and vibration may also be effective in a limited number of patients. The favorable risk-to-benefit ratio of all these modalities makes them reasonable alternatives for patients who cannot or will not undergo sympathetic neural blockade or tolerate pharmacologic interventions. The topical application of capsaicin may be beneficial in some patients suffering from phantom limb pain.

Low intensity laser therapy as well as a coordinated wellness program is also effective in treating this disorder.

Low Intensity Laser Therapy (LILT)

The low intensity Laser (LILT) sends photons (light) into the injured tissues and can penetrate two to three inches to treat affected areas. It uses a natural enhancement of the cellular machinery that can and has been dynamically measured in published studies to promote healing without burning affected tissue. Once the photons find the injured tissues, they stimulate and energize the cells to repair and strengthen at a remarkable rate. The treatment does not hurt, takes about 30 minutes and is very cost advantageous.

Wellness Program

A wellness program whichindividualizes treatment for age, performance and function has been shown in pilot studies to improve the overall health and well being of the individuals evaluated. A well conceived dietary and supplementary regimen based on scientific age–related decline in certain necessary compounds can improve quality of life, correct the ravages of hormone imbalance, balance critical neurotransmitter function without resorting to powerful drugs for depression that often have unfavorable side-effect profiles and restore vitality and youth in daily exercise routines. Furthermore, when wellness products are utilized with success, individuals often seek less costly interventions including unnecessary surgeries and narcotic options to treat pain. For more information go to www.drpwellness.com.