Amputation

A baffling medical phenomenon associated with amputation is the amputee's perception of a phantom limb. In these cases, which are quite common among amputees, the amputees will perceive their amputated limb as though it still exists as part of their body. This phantom limb may be so real to an amputee that he or she may actually try to stand on a phantom foot or perform some task such as lifting a cup with a phantom hand. Although amputees may feel a number of sensations in a phantom limb, including numbness, coldness, and heat, the most troubling sensation is pain. Approximately 70% of all amputees complain of feeling pain in their phantom limbs. Such pain ranges from mild and sporadic to severe and constant.

Although it probably is related to the central nervous system, the exact cause of the phantom limb phenomenon is unknown. Theories on the origin of the phantom limb phenomenon include impulses from remaining nerve endings and spontaneous firing of spinal cord neurons (nerve cells). More recent studies indicate that the phenomenon may have its origin in the brain's neuronal circuitry.

Treatments for phantom limb pain include excision (cutting out) of neuromas (nodules that form at the end of cut nerves), reamputation at a higher point on the limb, or operation on the spinal cord. Although success has been achieved with these approaches in some cases, the patient usually perceives pain in the phantom limb again after a certain interval of time.