MEMOIR – a clinical trial for Complex Regional Pain Syndrome

What is Complex Regional Pain Syndrome (CRPS)?  

CRPS is a disabling pain disorder. It affects approximately 5,000 people in Australia annually. CRPS is characterised by severe burning, stinging and stabbing pain. People with CRPS may not be able to use their affected limb and their ability to work or participate in normal social activities can be severely restricted. Currently, there are no interventions for CRPS whose efficacy is supported by high-quality evidence.

What is the MEMOIR Trial?

The MEMOIR trial is a Commonwealth Government-funded, randomised controlled trial testing two novel treatments for CRPS. MEMOIR will test whether a drug, memantine, and a rehabilitation program, Graded Motor Imagery, produce greater improvements in pain intensity and pain interference than placebo and standard care for CRPS.

The MEMOIR trial will be delivered remotely, via Telehealth, allowing Australia-wide recruitment of 160 participants. Eligible participants will be randomly allocated to one of the four treatment groups:

  • Memantine & Graded Motor Imagery
  • Placebo memantine & Graded Motor Imagery
  • Memantine & usual care
  • Placebo memantine & usual care

What is Memantine?

Memantine is currently approved in Australia for the treatment of moderately severe Alzheimer’s disease, but not for CRPS. Preliminary evidence suggests that memantine may be effective in reducing pain intensity in people with CRPS.

What is Graded Motor Imagery?

Graded Motor Imagery is a graded rehabilitation program that uses a combination of brain-directed movement activities and patient education. The Graded Motor Imagery activities include laterality tasks, imagined movements, mirror therapy and functional rehabilitation tasks. Preliminary evidence suggests that Graded Motor Imagery may be effective in reducing pain intensity and improving function in people with CRPS. The Graded Motor Imagery treatment protocol has been recently updated to be delivered in the MEMOIR trial.

What is usual care?

Usual care is the continuation of your current management for CRPS, excluding the therapies outlined in the exclusion criteria. This might include medical, physical or psychological management of CRPS.

Will these treatments improve my CRPS?

The effectiveness of these treatments is not known. We are attempting to find this out by conducting this research study. MEMOIR is the first, large, high-quality clinical trial to evaluate of the effects of memantine and Graded Motor Imagery for CRPS.

What is required as a MEMOIR participant?

Participation in this trial requires a large time commitment for participants. The time commitment varies depending on the group that you are allocated to. Study participants will be asked to:

  • Take oral memantine or placebo for 16 weeks and maintain daily records
  • Complete outcome questionnaires, four times throughout the study (these will take approximately 30 minutes to complete)
  • Participants receiving Graded Motor Imagery will attend 7, 60-minute physiotherapy sessions via Zoom and will complete online modules incorporating education and rehabilitative activities, for approximately 30-60 minutes each day, for 16 weeks
  • Participants receiving usual care will continue their current treatment, excluding any treatments that are listed in the study exclusion criteria

The trial treatment period will run for a period of 16 weeks. After this, we will require you to complete two further assessments at 6 months and 12 months.

Will I get paid to be a participant?

Participation in this study will not cost you anything, nor will you be paid.

What is MEMOIR’s eligibility criteria?

To be eligible for the MEMOIR trial, you must:

  • Have (or suspected to have) chronic CRPS of 6-36 months duration
  • Have at least moderate pain intensity and disability as measured by validated scales
  • Be 18 years of age or over
  • Have access to a computer (or tablet) and internet
  • Have CRPS in a single limb only

You will not be eligible to participate in the MEMOIR trial if:

  • You are female, of child-bearing potential and not using reliable contraceptive method(s)
  • You are pregnant and lactating
  • You have an allergy to the study drug family (NMDA antagonists)
  • You are taking high dose opioid analgesics or methadone
  • You are taking high dose anticonvulsant medicines
  • You are taking certain types of antidepressant medicines
  • You are taking anti-psychotic medicines
  • You have high blood pressure, or your blood pressure is managed with medicine
  • You have a heart-rhythm disorder, or you are taking a medicine to manage this condition
  • You have a kidney condition
  • You have a history of neurological conditions (stroke, seizure, Alzheimer’s)
  • You have an implanted spinal cord or nerve stimulator
  • You are currently using Graded Motor Imagery
     How do I participate?

If you meet the above criteria, are interested in participating and would like to assess your eligibility, please visit:


Please note that you will be informed of your preliminary eligibility at the conclusion of the survey. If you are preliminarily eligible, you will be provided with further details of the next screening steps and a copy of the MEMOIR Participant Information Statement.

How can I contact the MEMOIR study team?

02 9399 1627

MEMOIR Research Team

MEMOIR consolidates the expertise of the following international scientists and clinicians:

  • Prof James McAuley, School of Health Sciences & NeuRA, University of New South Wales
  • A/Prof Sylvia Gustin, School of Psychology & NeuRA, University of New South Wales
  • Prof Andrew McLachlan, Dean of Pharmacy, University of Sydney
  • Prof Lorimer Moseley, University of South Australia
  • Prof Benedict Wand, School of Physiotherapy, University of Notre Dame Australia
  • Dr Neil O’Connell, Brunel University London
  • Dr Hopin Lee, University of Oxford
  • Prof Eric Visser, School of Medicine, University of Notre Dame Australia
  • Prof Sallie Lamb, University of Exeter
  • Mr Michael Ferraro, NeuRA, University of New South Wales
  • Dr Aidan Cashin, NeuRA, University of New South Wales
  • Dr Saurab Sharma, NeuRA, University of New South Wales


The MEMOIR trial has been approved by the Ethics Review Committee (RPAH Zone) of the Sydney Local Health District, protocol number: X20-0325.