Mirror Therapy Combined with TENS for Motor Recovery in Paretic Upper Limbs of Chronic Stroke Patients

The aim of this study is to determine whether mirror therapy, applied in addition to bilateral upper extremity transcutaneous electrical nerve stimulation in patients with chronic stroke, has an additive effect on upper extremity motor control

A prospective, double-blind, randomized controlled clinical trial included 30 chronic stroke patients. The patients were randomly assigned to the Mirror group (n=15) and the Control group (n=15). At the end of the three-month follow-up period, 10 patients in the Mirror group and 14 patients in the Control group completed the study. Both groups received conventional rehabilitation therapy for a total of 20 sessions (5 days a week for 4 weeks), in addition to 30 minutes of transcutaneous electrical nerve stimulation (TENS) applied to the bilateral extensor muscles of the hand. In the Mirror group, mirror therapy was additionally applied after the TENS intervention. Patients were evaluated by a blinded assessor for motor recovery of the upper extremity and hand at baseline, at the mid-point (10th session), at the end of treatment (1st month), and 2 months after the end of treatment. The primary outcome measure was the Fugl-Mayer Assessment Scale for Upper Extremity (FM-UE), and the secondary outcome measure was the Brunnstrom Staging for the upper extremity and hand.

The effect size (Cohen's d = 0.314) used to calculate the minimum sample size for detecting a significant difference between groups (Bi-TENS + Mirror therapy, Bi-TENS) was obtained from a previous study. (Peiming ve ark. 2021) The sample size was then calculated using the G\*Power software version 3.1.9.4 (Franz Faul, University of Kiel, Germany), with an alpha error level of 0.05, a power of 0.95, an inter-correlation of 0.5, and a global non-correlation of 1. The total sample size required for this study was calculated to be 24. Assuming a dropout rate of 20%, the total sample size was determined to be 30.

The normality of the variables was assessed graphically and using the Shapiro-Wilk test. Data that followed a normal distribution were summarized as Mean ± Standard Deviation, while data that did not follow a normal distribution were summarized as Median and the interquartile range (Q1-Q3). Categorical variables were summarized as frequency (percentage). Comparisons of means between groups were performed using the Independent Samples t-test if the data followed a normal distribution, and the Mann-Whitney U test if the data did not follow a normal distribution. For categorical variables, comparisons between groups were made using the Chi-square test or Fisher's Exact test. Intra-group comparisons of means were performed using repeated measures ANOVA. Bonferroni correction was applied for post-hoc pairwise comparisons. A statistical significance level of p \< 0.05 was considered. Statistical analyses and calculations were performed using IBM SPSS Statistics 21.0 (IBM Corp. Released 2012. IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp.) and MS-Excel 2007.

Eligibility Criteria:
Inclusion Criteria:

* Individuals with a history of unilateral stroke
* Cases with a stroke duration of \>6 months
* Brunnstrom stage for the upper extremity ≥3
* Brunnstrom stage for the hand ≥4
* Mini-mental test score \>21
* Normal vision and hearing functions

Exclusion Criteria:

* Individuals with aphasia
* Individuals with neglect
* Those with a history of traumatic brain injury
* Individuals with uncontrolled cardiovascular disease
* Active inflammatory rheumatological or infectious diseases
* Individuals with significant upper extremity peripheral neuropathy
* Those with severe sensory deficits
* Individuals with severe shoulder, elbow, wrist, or finger contractures
* Individuals with a cardiac pacemaker
* Those with lesions on the skin of the upper extremity
* Individuals with skin allergies