HETEROGENEITY OF PRACTICE AND LACK OF DESCRIPTION OF MIRROR THERAPY INTERVENTION IN PHANTOM LIMB PAIN TREATMENT: A SCOPING REVIEW

M. Guemann¹, K. Arribart²

¹University School of Physiotherapy, Orléans, France, ²Centre Robert Merle d'Aubigné, Valenton, France

Background: Phantom limb pain is devastating for every patient experiencing it. It is defined as a painful sensation perceived in the missing portion of the amputated limb which differs from the residual limb pain perceived at the stump level and from phantom limb sensation which is a non-painful sensation perceived in the missing part of the limb. The prevalence of this painful condition was estimated at 64% and can go up to 85%. The mechanisms involved in the development of PLP are still unclear. Mirror therapy for the treatment of phantom limb pain shows promising results but suffers from lack of evidence and heterogeneity among studies. To better understand this heterogeneity, a scoping review was conducted.

Purpose: The purpose of this scoping review was
(i) to map the extent of practice regarding the use of mirror therapy in the treatment of phantom limb pain,
(ii) to gather details about the content and duration of mirror therapy sessions,
(iii) to observe if a certain homogeneity or heterogeneity of practice could explain the lack of evidence for this treatment, and finally,
(iv) to provide recommendation elements for future research work to standardize practice an assessment of MT efficacy.

Methods: Seven databases were explored (CENTRAL, Clinicaltrial.gov, CochraneDatabase of Systematic Reviews, Physiotherapy Evidence Database (PEDro), Pubmed, Sciences Direct and Scopus). Two independent reviewers selected, assessed, and extracted the data about the population, mirror therapy practice, and pain evaluation. Included articles concern all types of design dealing with the use of mirror therapy to treat phantom limb pain. Randomized control trials were assessed using the PEDro scale. The research was conducted between 1995 and May 2022.

Results: Forty-three articles were selected which gather 15 randomized control trials, 14 prospective cohort studies, 12 case reports and 2 protocols. All studies totalized 841 persons where men (70%) are more represented than women; treatment of the lower limb (87%) was more explored than the upper limb and the major cause of amputation was trauma (50.5%). Pain was evaluated mostly by a visual analog scale (63%). Internal validity of randomized control trials was moderate (mean of 5.4 on the PEDro scale). There was a lack of description of the mirror therapy sessions, particularly regarding the number of exercises, time per exercise and number of repetitions. Most sessions were 15 minutes long, with one session per day. Exercises displayed were mostly motor exercises of the distal part of the limb.

Conclusions: Mirror therapy is a technique used worldwide that suffers from a lack of evidence for its effects due to a great heterogeneity of practice, poor description, and the absence of a standardised protocol. Future work should fill these gaps to allow better reproducibility and strengthen the evidence for its effectiveness.

Implications: Mirror therapy might be an interesting technique to use with patients suffering from phantom limb pain. Its effect is not fully understood yet and may be overestimated. More rigorous studies should be conducted with good reporting and maybe, the combination of approaches including mirror therapy should be evaluated.

Funding acknowledgements: This work was supported by the Biomedical Research Institute of Armed Forces

Keywords:
Amputation
Mirror Therapy
Phantom limb pain

Topics:
Pain & pain management
Orthopaedics
Neurology

Did this work require ethics approval? No

Reason: This is secondary research, only working with published data.