The authors of the study interviewed 27 participants who had been diagnosed with Complex Regional Pain Syndrome. Pain in a limb is the main symptom in CRPS. Patients with CRPS have been noted to neglect their affected limb, rather than being overattentive, or protective of the limb as might be expected. CRPS has been described as having neurological neglect-like symptoms similar to some people after having a stroke. The authors proposed that this might not be an accurate description, but that body perception disturbance more accurately described the phenomenon.
The authors explored participants’ feelings and perceptions about their affected body parts. They hoped the participants would describe their perceptions about the affected limb both physically and emotionally. Pain, depression, and general health status were measured with the commonly used Brief Pain Inventory, the Beck Depression Inventory, and the SF-36. The small sample of participants were noted to have moderate pain intensity, were physically limited, and had mild to moderate depression ratings.
Pain was described in several common themes. These were hostile feelings, disassociation of the limb, and disparity between what is visually apparent and what is felt. Other themes included, distorted mental images of the affected part, and conscious attention.
Feelings of hostility ranged from mild frustration to more intense experiences such as hate, disgust, and repulsion of the affected part. Disassociation was described as psychological detachment of the affected limb from the remainder of their unaffected body. Some even desired getting rid of the pain by amputation of the affected limb. Many participants reported that the affected limb looked differently than it felt. Feelings of size, pain, and temperature varied with the way the limb actually looked. Mental pictures of the affected limb were distorted in comparison to their unaffected opposite limb, but only certain parts of the limb, not the whole limb. While participants reported their awareness of the affected limb was heightened due to the pain, they typically had difficulty in knowing its position. Some participants avoided looking or touching their affected limb. In some cases they hid the limb from their field of view. Others touched their limb routinely to check it. Others had to concentrate on their limb to move it.
Those with mild disease described fewer disturbances than those with more severe disease. Reduced body perception disturbance appeared to decrease symptoms, particularly pain.
In CRPS, there seems to be a complex interaction between pain, disturbances in body perception and central remapping in the brain. Brain imaging studies confirm this. These findings may support the use of treatments that target cortical areas of the brain to reduce body perception disturbances and therefore pain in CRPS.