Causalgia that is the alternate name for RSD is a Latin word which means “burning pain”. More often than not RSD patients suffer from intense pain coupled with burning sensation. However, to know the exact extent of pains suffered by a person the indicator used is known as McGill Pain Index.

There are many versions of McGill Pain Index. One of the versions is also used to calculate the pain ratio in case of patients suffering from RSD or CRPS. Developed initially in 1971, the McGill Pain Index gauges the quality of pain. Since it was developed in McGill University by Melzack and Torgerson it is called McGill Pain Index.

Several pointers are used to exactly calculate the pain proportion in a RSD patient. In calculation, the RSD Injuries are also taken into count since they have a major role to play in developing RSD and sufferance of the patient. Some of the pointers are sensory qualities like tension, fear, and sensitivity. Pressure and environmental changes are also taken into account at the time of calculating the intensity of pain suffered.

Doctors and scientists world over have accepted the McGill Pain Index as the universal indicator of RSD Progression in the body of a patient. The tool is especially useful in dealing with a chronic pain since it is both viable and reliable.