The effects of the mirror therapy on shoulder function in patients with breast cancer following surgery: a randomized controlled trial.

Purpose: Shoulder dysfunction is one of the most bothersome questions for breast cancer survivors. Studies show that mirror therapy can improve shoulder function in patients with a limited shoulder range of motion and shoulder pain. Here, this article reports the results of a randomized controlled trial investigating the effects of the mirror therapy on shoulder function in patients with breast cancer following surgical treatments.

Methods: Totally, 79 participants were divided to two groups receiving active range-of-motion upper limb exercise based on the mirror therapy or active range-of-motion upper limb exercise respectively for 8 weeks. Shoulder range of motion, Constant-Murley Score, Disabilities of Arm, Shoulder, and Hand Questionnaire, Tampa Scale of Kinesiophobia, Visual analog scale, and grip strength were measured at baseline (T0), 2 weeks (T1), 4 weeks (T2), and 8 weeks (T3). The effects of the intervention on shoulder function were analyzed in generalized estimation equation, from group, time, and the interactions between group and time based on the data from participants who completed at least one post-baseline observation RESULTS: At least one post-baseline observation was performed by 69 participants (n=34 mirror group, n=35 control group). 28(82.35%) participants in the mirror group adhered to the exercise compared to 30(85.71%) in the control group. Generalized estimation equation model showed group had main effects on forward flexion (Waldχ²=6.476, P=0.011), with the Cohen's d=0.54. The effects of the group on abduction, Constant-Murley Score, and Disabilities of Arm, Shoulder, and Hand Questionnaire were significant when fix the effects of the time. At 8 weeks, participants in the mirror group showed an improvement in abduction compared to the control group (P=0.005), the Cohen's d was 0.70. At 8 weeks, participants in the mirror group had a higher Constant-Murley Score than control group (P=0.009), with Cohen's effect size value of d=0.64. The mirror group showed a greater improvement on the Disability of Arm, Shoulder, and Hand Questionnaire than control group at 2 weeks, 4 weeks, and 8 weeks (P≤0.032), but with a weak effect size value of all (r≤0.32). Group had main effects on Tampa Scale of Kinesiophobia (Waldχ²=6.631, P=0.010), with the Cohen's effect size value of d=0.56.

Conclusions: Mirror therapy improved shoulder flexion, abduction, shoulder function in daily life, and arm function and symptom of the affected shoulder in patients with breast cancer following surgical treatment, while decreasing fear of movement/(re)injury. Mirror configuration needs to be improved in further research to increase its feasibility.

Implications For Cancer Survivors: Breast cancer survivors can try mirror therapy as a practical and effective method in shoulder rehabilitation for a promotion on effects.

Trial Registration: ClinicalTrial.gov Identifier: ChiCTR2000033080.