A phantom limb is a vivid perception that a limb that has been removed or amputated is still present in the body and performing its normal functions. Amputees usually experience sensations including pain in the phantom limb.
Studies suggest that 90 to 98% of patients suffer from phantom limb right after amputation or loss of the limb. Removal of parts other than the limbs may also cause phantom sensations. For example, removal of an eye or a breast or a tooth extraction can cause phantom perceptions. People born without a limb can also experience such phantom sensations.
This phantom limb phenomenon has been found to be caused by the changes occurring in the cortex of the brain following amputation of a limb. It has been found that the brain continues to receive signals from the nerve endings that originally supplied signals to and from the missing limb. It is also thought to be caused by the brain rewiring itself and rearranging sensory information to adjust to the changes in the body.
In many patients, the phantom body part is perceived for a few days or weeks after loss or removal of the part, while in others the phantom may persist for years after amputation.
Symptoms of Phantom Limb Syndrome
Patients suffering from this syndrome perceive that the amputated limb is still present and functioning as usual. In many cases, patients experienced a range of sensations in the phantom limb.
These sensations include:
- A tickling feeling
- A shooting, piercing, or stabbing pain
- Numbness and even pleasure.
Some patients may also feel other sensations such as cold, warmth, tightness and itchiness.
While these symptoms can be mild in some patients, in others, they can be debilitating and interfere with their day-to-day activities.
Patients often feel that the phantom limb is distorted or shorter than the original limb. In the case of removal of a deformed limb or body part, the deformity is usually carried over to the phantom. In some cases involving phantom hands, patients felt that the phantom arm becomes shorter over time and after a point only the phantom hand is left dangling from the stump. This is called telescoping and is believed to be caused by the conflicting sensory signals received by the brain of such patients. Eventually the brain learns to inhibit all such conflicting signals and hence the phantom fades away.
Some factors that might contribute to the development of this syndrome in amputees include:
- Pain or infection prior to amputation
- Presence of blood clots in the amputated limb
- Traumatic amputation
- Type of anesthesia used during the removal of limb
The phantom limb phenomenon is seen more commonly in adults than in children, probably because the brain, in the case of children, had not finished consolidating images of external organs in the body.
Treatment of Phantom Limb
Coping techniques such as muscle relaxation, meditation, biofeedback, massage and hypnosis has been shown to help some patients deal with phantom pain or related symptoms. Drugs such as analgesics, muscle relaxants, sedative-hypnotics, antidepressants, antipsychotics and anticonvulsants are commonly used in treating phantom pain.
In some cases, shock therapy and acupuncture have been used to relieve symptoms. When non-invasive treatments fail to work, invasive approaches such as stimulation of the spinal cord, intrathecal drug delivery and deep brain stimulation have been used to treat phantom pain.
Electrical nerve stimulation techniques such as transcutaneous electrical nerve stimulation and transcranial magnetic stimulation have been found to be beneficial in some patients. It is also believed that administering pain relieving medicines before amputation decreases the chances of developing phantom pain after the surgery.
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Reviewed by Yolanda Smith, BPharm