Motor imagery as a complementary technique for functional recovery after stroke: a systematic review.

Background: Stroke is the leading cause of disability in adults, producing a major personal and economic impact on those affected. The scientific evidence regarding the use of Motor Imagery (MI) as a preparatory process for motor control reinforces the need to explore this method as a complement to physical therapy. Objectives: The objectives of this systematic review were to determine the effectiveness of MI for functional recovery after stroke and to identify a possible intervention protocol, according to the level of existing scientific evidence. Methods: A comprehensive literature search was performed using Medline, Cochrane Library and PEDro databases. Studies were limited to those published between 2007 and 2017, and restricted to English and/or Spanish language publications. Results: Thirteen randomized clinical trials that met the inclusion criteria were included. The methodological quality of studies was determined using the Critical Review Form for Quantitative Studies, obtaining scores of 9-13 points out of 15. The level of evidence and strength of recommendations were assessed using the U.S. Preventive Services Task Force (USPSTF) assessment, obtaining levels IA and II-B1. Significant improvements were found in outcome measures evaluating upper limb functionality, balance and kinematic gait parameters. Conclusions: The use of MI combined with conventional rehabilitation is an effective method for the recovery of functionality after stroke. Due to the great heterogeneity in the scientific literature available, new lines of research are necessary, in order to include well-designed studies of good methodological quality and to establish a consensus regarding the most appropriate protocols.