Phantom Limbs

The phantom limb is a phenomenon that arises in patients who have undergone an amputation procedure, but who continue to have the sensation that the absent limb is attached and present. Although it is most often reported in cases regarding the loss of a limb, it is also known to occur following the loss of other body parts, such as the eyes and tongue (Flor, 2002). This perception is separated into three distinct sensations. The first is pain in the residual limb, which refers to pain felt in the physically remaining portion of the limb at the site of amputation, most common directly following the procedure. The second, and almost invariably reported experience of patients, is phantom sensation, referring to any sensation of the absent limb’s presence, including tingling, temperature, touch and itching, but not including pain. It can be so vivid that the patient attempts to use the absent limb, and frequently includes the feeling of telescoping, where the phantom limb is perceived to retract into the residual limb. Lastly, the third distinction is phantom pain, which are those sensations felt in the absent limb that the patient describes as painful (Hill, 1999).

            Current research believes that phantom limb is related to a reorganization of the somatosensory cortex, thalamus, and parietal cortex. The somatosensory cortex is associated with the perception and memory of pain, and sufferers of chronic back pain have shown a relationship between their experience of pain and an over representation of that particular area in the somatosensory cortex. In cases where portions of the cortex have been removed, patients report the cessation of the sensation of pain in the absent limb, and transversely, patients who have had the cortex stimulated reported an onset of phantom pain, suggesting the absent limb may be overly represented in the somatosensory cortex (Flor, 2002). Activity in the thalamus is indicative of continued response to the presence of the absent...