Perineural catheters that provide local anesthetic agents have poor evidence of success when placed after surgery in an effort to prevent phantom limb pain.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.Although mirror therapy was introduced by VS Ramachandran in the early 1990s, little research was done on it before 2009, and much of the subsequent research has been of poor quality, according to a 2016 review. A 2018 review, which also criticized the scientific quality of many reports on mirror therapy (MT), found 15 good-quality studies conducted between 2012 and 2017 (out of a pool of 115 publications), and concluded that "MT seems to be effective in relieving PLP, reducing the intensity and duration of daily pain episodes. It is a valid, simple, and inexpensive treatment for PLP." Other phantom sensations
Phantom sensations may also occur after the removal of body parts other than the limbs, e.g. after amputation of the breast, extraction of a tooth (phantom tooth pain) or removal of an eye (phantom eye syndrome).Some people who have undergone gender reassignment surgery have reported the sensation of phantom genitals. The reports were less common among post-operative transgender women, but did occur in transgender men. Similarly, subjects who had undergone mastectomy reported experiencing phantom breasts; these reports were substantially less common among post-operative transgender men.
Pain researchers such as Tamar Makin (Oxford) and Marshall Devor (Hebrew University, Jerusalem) argue that phantom limb pain is primarily the result of "junk" inputs from the peripheral nervous system.Despite a great deal of research on the underlying neural mechanisms of phantom limb pain there is still no clear consensus as to its cause. Both the brain and the peripheral nervous system may be involved.Research continues into more precise mechanisms and explanations. Neural mechanisms
Pain, temperature, touch, and pressure information are carried to the central nervous system via the anterolateral system (spinothalamic tracts, spinoreticular tract, spinomesencefalic tract), with pain and temperature information transferred via lateral spinothalamic tracts to the primary sensory cortex, located in the postcentral gyrus in the parietal lobe, where sensory information is represented somatotropically, forming the sensory homunculus.In phantom limb syndrome, there is sensory input indicating pain from a part of the body that is no longer existent. This phenomenon is still not fully understood, but it is hypothesized that it is caused by activation of the somatosensory cortex. Treatment
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.