Friday, August 24, 2007

Complex Regional Pain Syndrome and GMI

At NOI, we often get requests for advice using the graded motor imagery programme (GMI).

A typical question may be: Can you offer any assistance and advice using the GMI programme for a 30 year old female who has a four year history of Complex Regional Pain Syndrome (CRPS), post right wrist fracture. Her pain has also spread into her right lower limb.

Here is a suggested start:

1. Review in your own mind what CRPS is. It is perhaps best considered as a multi-mechanismed disorder with likely nociception from tissues, some adrenaline sensitive nerves, an upregulated central nervous system with a perturbed sympathetic nervous (SNS) system. The SNS is just one of a number of body systems used as a defense. It is possible that there will be altered endocrine, pain and immune systems as well. One of the processes in the upregulated CNS is likely to be distortion of the arm’s representation in the brain.

2. Although there is no direct evidence, we can extrapolate from existing research and use anecdotes to suggest that GMI works better if a person understands the biology of what has happened to them, in particular, the notion that the brain is the prime therapeutic target. Use of the explanatory book “Explain Pain” is suggested.

3. Perturbed sympathetic nervous systems are more likely to have occurred due to real or perceived threats to the person, rather than input from the damaged wrist, though the wrist inputs will contribute. These threats could be wide ranging (why hasn’t therapy worked, what is wrong with me, will my family life hold up, etc etc) and need identification.

4. The most recent of example of literature demonstrating efficacy of GMI is Moseley, GL (2006) "Graded motor imagery for pathologic pain." Neurology 67: 1-6. This paper has a substantial reference list.

5. Clinical trials are guides only. For management, the clinical trial material must be placed with all the clinical evidence associated with a particular individual. Research can homogenize patients. Chronic pain states such as CRPS are characterized by variability in presentation.

6. Useful information emerging from Moseley’s research suggests that GMI really should be graded! That is a person should have a good sense of laterality first, before moving onto various motor imagery tasks, before moving onto mirror work. This makes a lot of sense. If the reader was to look at another person’s hand and imagine that their own hand is in that position, the brain would first have to compute that it was a left or right hand, otherwise there will be a bit of intracranial confusion and synaptic stress.

More practicalities, especially related to the patient and use of laterality in the next posting. Please send questions and queries to