The purpose of this pilot study was to compare bimanual and unimanual mirror therapy (MT) protocols, in upper-limb (UL) recovery poststroke during a 6-wk home MT program to determine if one is superior to the other. We hypothesized that unimanual MT (UMT) would be superior to bimanual MT (BMT), because the latter may cause a conflict between proprioception and visual feedback.

BACKGROUND: MT involves a mirror box being placed between the arms of a patient with the affected hand in the mirror box. The patient moves the unaffected hand while observing the mirror reflection superimposed on the affected hand (Ramachandran, Rogers-Ramachandran, & Cobb, 1995). During UMT, the affected hand is static, whereas in BMT the affected hand imitates the unaffected hand. Selles et al. (2014) compared the two MT protocols during a short training program, that showed greater gains with UMT. However, there is no research comparing the two MT protocols during a longer intervention with functional outcomes.

METHOD: This was a single-blinded randomized controlled pilot study. Participants were recruited from an occupational therapy (OT) department in an urban medical center. Eligible participants were randomized into UMT, BMT, or traditional OT (TOT) home program. All participants received OT 2×/wk, as well as a home program for 30 min a day, 5 days/wk for 6 wk, as per group allocation. Weekly sessions with the research OT occurred to progress the home program. Inclusion criteria for eligibility were ≥3 mo poststroke; ages 19–85; ability to follow directions; Fugl-Meyer Assessment (FMA) between 10 and 50, and ability to grasp and release a washcloth. The following usual and customary stroke research outcome measures were used pre- and posttreatment: UL–FM, which measures recovery poststroke; Action Research Arm Test (ARAT), a 19-item objective assessment for UL function; and the Stroke Impact Scale (SIS), a 59-item questionnaire assessing health status poststroke. Demographic data were collected, including age, gender, race, and time since stroke. Data, including mean, standard deviation, and change scores (CS; post – pre), were compared between treatment groups.

RESULTS: We recruited 6 participants: 2 per group, 50% men; ages ranged from 34 to 73. All groups improved on the FMA and ARAT; however, UMT had the greatest change scores on the FMA (UMT = 9.5, BMT = 9, TOT = 8) and ARAT (UMT = 9, BMT = 7, TOT = 2). For SIS activities of daily living, UMT (20) and BMT (21) improved more than TOT (10), whereas for SIS strength, the UMT improved the most (UMT = 10, BMT = 5,TOT = 7.5). However, for participation, the TOT improved the most (UMT = 4, BMT = 6,TOT = 11).

DISCUSSION: Our preliminary results are consistent with previous studies that have suggested MT has a positive effect on UL recovery poststroke (Thieme, Mehrholz, Pohl, Behrens, & Dohle, 2012). Furthermore, our results suggest that UMT may be more effective than BMT at improving UL function and provide initial support for the use of UMT as a home treatment program.

IMPACT STATEMENT: MT therapy is used in practice; however, no studies have compared the two MT protocols for UL recovery. This pilot study is an important step in deciphering the superiority of the available protocols and furthers our knowledge regarding best practice for the use of MT for UL recovery poststroke.

Ramachandran, V. S., Rogers-Ramachandran, D., & Cobb, C. (1995). Touching the phantom limb. Nature, 377, 489–490. http://dx.doi.org/10.1038/377489a0

Selles, R. W., Michielsen, M. E., Bussman, J., Stam, H. J., Hurkmans, H. L., Heijnen, I., . . . Ribbers, G. M. (2014). Effects of a mirror-induced visual illusion on a reaching task in stroke patients: Implication for mirror therapy training. Neurorehabilitation and Neural Repair, 28, 1–8. http://dx.doi.org/10.1177/1545968314521005

Thieme, H., Mehrholz, J., Pohl, M., Behrens, J., & Dohle, C. (2012). Mirror therapy for improving motor function after stroke. Cochrane Database of Systematic Reviews, 2012, CD008449. http://dx.doi.org/10.1002/14651858.CD008449.pub2