Scientific evidence behind Graded Motor Imagery
Evidence base for the use of the Neuro Orthopaedic Institute’s Graded Motor Imagery Handbook, Recognise Apps Flash Cards and Mirror Box.
Neuro Orthopaedic Institute (NOI) holds the view that evidence based practice is the integration of clinical expertise acquired from clinical experience with the best external evidence from clinical trials and research from basic sciences (Sackett et al., 1996).
Graded Motor Imagery is a sequence of strategies including laterality restoration (being able to identify left and right limbs), motor imagery and use of a mirror box. The therapeutic target is the process in the central nervous system broadly referred to central sensitivity. Evidence for the use of the GMI process or its individual components comes from neuroscience and clinical trials.
Therapeutic tools suggested for laterality recognition are the Recognise Flash Cards and the Recognise Apps. A Mirror Box is required for mirror therapy.
Clinical trial evidence
In the most recent randomised controlled trial, the graded motor imagery package has demonstrated good evidence for outcome (reduced pain and disability) in Complex Regional Pain Syndrome1 (CRPS1) (Moseley, 2004a, 2005) and CRPS1 and phantom limb pain (Moseley, 2006). It works best if carried out in the sequence of laterality recognition, motor imagery and mirror therapy (Moseley, 2006).
A recent systematic literature review of graded motor imagery in CRPS 1 advocates its use to reduce pain (Daly AE, Bialocerkowski AE, 2008). There is good evidence for the use of mirror therapy alone for acute CRPS (McCabe et al., 2003; McCabe et al., 2004).
Mirror therapy alone for phantom limb pain has shown benefits in small trials (McLachlan et al., 2004; Ramachandran & Rogers- Ramachandran, 1996). There are case reports of successful mirror therapy management of CRPS (Karmarker & Lieberman, 2006) and post hand surgery pain (Rosen & Lundborg, 2005) in respected medical journals.
Vladimir Tichelar et al., (2007) demonstrated benefits of mirror box therapy with cognitive behavioural therapy in three patients with CRPS1.
CRPS and phantom limb pain are severe neuropathic pain states. It would seem that the GMI process would be beneficial for other pain states such as overuse syndromes (variously focal dystonia, repetition strain injury, cumulative trauma disorder) and various arthritic syndromes. Anecdotal evidence supports this contention, suggesting that trials are worthy.
Basic sciences evidence
The pathobiological target of graded motor imagery techniques is the process broadly known as central sensitisation. For a recent review see Campbell and Meyer (2006). This includes changes such as cortical reorganisation where brain parts dedicated to body parts and function anatomically change. The advent of brain mapping techniques such as functional magnetic resonance imaging have provided a solid science foundation to notions of cortical reorganisation. Systems of ‘mirror neurones’ exist in the brain (Gallese et al., 1996) and are activated by watching movement or imagined movement.
Loss of laterality recognition is known to occur in patients with CRPS and phantom limb pain. (Moseley, 2004b; Nico et al., 2004; Schwoebel et al., 2002).
Attempts at limb laterality recognition activates pre motor (association) cortices, not the primary motor cortex, allowing a selective and graded therapy (Moseley et al., 2003).
Production and perception of motor action activates common brain parts (Blakemore & Decety, 2001; Grezes & Decety, 2001) allowing imagery to be a way of ‘exercising’ neurones in a graded programme.
Blakemore, S. J., & Decety, J. (2001). From the perception of action to the understanding of intention. Nature Reviews Neuroscience, 2, 561-567.
Campbell, J. N., & Meyer, R. A. (2006). Mechanisms of neuropathic pain. Neuron, 52, 77-92.
Daly A.E. & Bialocerkowski A.E. (2008) Does evidence support physiotherapy management of adult CRPS 1? A systematic review. Eur J Pain (2008), doi:10.1016/j. ejpain.2008.05.003
Gallese, V., Fadiga, L., Fogassi, L., & Rizzolatti, G. (1996). Action recognition in the premotor cortex. Brain, 119, 593-609.
Grezes, J., & Decety, J. (2001). Functional anatomy of execution, mental simulation, observation and verb generation of actions: A meta-analysis. Human Brain Mapping, 12, 1-19.
Karmarker, A., & Lieberman, I. (2006). Mirror box therapy for complex regional pain syndrome. Anaesthesia, 61, 412-413.
McCabe, C. S., Haigh, R. C., Ring, E. F. R., Halligan, P., & Blake, D. R. (2003). A controlled pilot study of the utility of mirror visual feedback in the treatment of complex regional pain syndrome (type 1). Rheumatology (Oxford), 42, 97-101.
McCabe, C. S., Haigh, R. C., Shenker, N. G., Lewis, J., & Blake, D. R. (2004). Phantoms in rheumatology. Novartis Foundation Symposia, 260, 154-174.
McLachlan, M., McDonald, D., & Waloch, J. (2004). Mirror treatment of lower limb phantom pain: A case study. Disability and Rehabilitation, 26, 901-904.
Moseley, G. L. (2004a). Graded motor imagery is effective for long standing complex regional pain syndrome. Pain, 108, 192-198.
Moseley, G. L. (2004b). Why do people with complex regional pain syndrome take longer to recognise their affected hand? Neurology, 62, 2182-2186.
Moseley, G. L. (2005). Is successful rehabilitation of complex regional pain syndrome due to sustained attention to the affected limb. Pain, 114, 54-61.
Moseley, G. L. (2006). Graded motor imagery for pathologic pain. Neurology, 67, 1-6.
Moseley, G. L., Schweinhardt, P., Wise, R., & Tracey, I. (2003). Virtual, imagined and mirror movements – a novel approach to complex regional pain syndrome (crps1). Paper presented at the Europ Fed IASP Chapt Triennial Conference, Prague.
Nico, D., Daprati, E., Rigal, F., Parsons, L., & Siragu, A. (2004). Left and right hand recognition in upper limb amputees. Brain, 127, 120-132.
Ramachandran, V. S., & Rogers- Ramachandran, D. (1996). Synaesthesia in phantom limbs induced with mirrors. Proceedings of the Royal Society of London B., 236, 377-386.
Rosen, B., & Lundborg, G. (2005). Training with a mirror in rehabilitation of the hand. Scand J Plast Reconstr Surg Hand Surg, 39, 104-108.
Sackett, D. L., Rosenberg, W. M. C., Muir, J. A., & al., e. (1996). Evidence based medicine: What it is and what it isn’t. British Medical Journal, 312, 71-72.
Schwoebel, J., Coslett, H. B., Bradt, J., Friedman, R., & Dileo, C. (2002). Pain and the body schema: Effects of pain severity on mental representations of movement. Neurology, 59, 775-777.
Vladimir Tichelar, Y. I., Geertzen, J. H., Keizer, D., & van Wilgen, P. V. (2007). Mirror box therapy added to cognitive behavioural therapy in three chronic complex regional pain syndrome type 1 patients: A pilot study. Int J Rehabil Res, 30, 181-188.