Background & Aims

Current treatments for CRPS have limited efficacy, can have significant side effects, or be uncomfortable for patients. Safe, cost-effective and clinically effective treatments are needed. Body illusions, such as mirror therapy and resizing, have shown promise. Virtual reality is a cost-effective modality through which more powerful body illusions can be provided that can also be comfortable, very distracting and motivating for the patient. Performing VR exercises with an embodied virtual body has been shown to be analgesic in some conditions, but has not been tested in CRPS. The aim of this study is to assess whether daily use of an immersive VR rehabilitation program in patients with chronic lower extremity CRPS is acceptable to patients, feasible, tolerable, and whether there are signs of clinical efficacy with respect to reducing pain, kinesiophobia, disability, and body disturbances compared to baseline after a treatment period of 4 weeks.

Methods

This study is a pilot study of 5 adult patients with chronic lower limb CRPS, determined according to the Budapest criteria. Recruited patients used an at-home VR program 5-7 times per week for 4 weeks, each session consisting of 20 minutes of virtual rehabilitation. In the program, they observed a similar virtual avatar, seen from a first-person perspective, perform a series of progressive movements and activities, without any actual physical movement. We measured pain quality and intensity, kinesiophobia, alterations in body perception, and skin changes at baseline, after treatment (4 weeks). In addition, we conducted detailed interviews with each patient to try to determine the feasibility, tolerability, and acceptability of the program.

Results

Previous studies using VR for CRPS have found a decrease in pain ratings of up to 50% right after VR use. Our mid term study of pain outside VR after a 4 week period did not result in a decrease in pain ratings. However, there was an effect on kinesiophobia in four of five patients that well exceeded the reported MCID for chronic pain, which may be clinically useful to reduce anxiety and improve motivation before participating in a physical rehabilitation program. Qualitative analysis suggests that the intervention is feasible, acceptable and tolerable to patients; however, several suggestions for improvement were made that may help improve these aspects.

Conclusions

Regular use of an immersive VR exercise program featuring virtual embodiment has signs of clinical efficacy in reducing fear of movement in adult patients with chronic CRPS, in addition to being generally feasible, tolerable and acceptable. The reduction of kinesiophobia may result in increased movement, reduced anxiety, increased motivation of rehabilitation and improvement of life quality. Tolerance and acceptability may vary depending on the severity of CRPS symptoms and individual preferences. Optimizing VR equipment for comfort and user-friendliness is crucial for long-term use by CRPS patients. Larger controlled studies are warranted to confirm these findings and explore the long-term tolerability of VR use in CRPS patients.

References

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Presenting Author

Anthony Donegan

Poster Authors

Anthony Donegan

MSc

IDIBAPS

Lead Author

E-mail

Beñat Amestoy Alonso MSc

IDIBAPS

Lead Author

E-mail

Judith Sanchez-Raya PhD

MD

Vall d'Hebron University Hospital

Lead Author

E-mail

Anna Server Salva PhD

MD

Vall d'Hebron University Hospital

Lead Author

E-mail

Francisco Medel Rebollo MD

Vall d'Hebron University Hospital

Lead Author

E-mail

Rosa Ruiz Hudd MD

Vall d'Hebron University Hospital

Lead Author

E-mail

Maria V. Sanchez-Vives MD

PhD

IDIBAPS

Lead Author

E-mail

Topics

  • Specific Pain Conditions/Pain in Specific Populations: Complex Regional Pain Syndrome (CRPS)