Effect of Mirror Therapy on Upper Limb Function: A Single Subject Study

Mirror therapy is a unique treatment with a touch of modality that is purported to improve the motor function of the affected limb in individuals with hemiplegia. Previous studies have focused on the neuro-physiological factors underlying the mechanism of the clinical effect of this technique. The present study aims to understand the mechanism using the rehabilitation method and neuro-occupation model as well as analyze the effects of mirror therapy on the upper limb function of subjects with spastic hemiplegic cerebral palsy.
Single subject design known as withdrawal design was used by a convenience sample of four subjects. The study involved three observational phases known as baseline, treatment, and withdrawal phases that took place during a 10 week period. The study contained a home-based mirror therapy protocol whereby the participants were instructed to do some exercises on a daily basis. The improvement of the hand function of the hemiplegic side was examined by Box and Block test along with two more activities including Threading Beads and Stacking Rings.
The ability to perform the Box and Block test, Threading Beads, and Stacking Rings tended to remain steady in the baseline phase, whereas there was a noticeable improvement during the treatment phase and a decline in the withdrawal phase.
From the perspective of visual feedback neuro-occupation model, it could be hypothesized that alterations to the sensory system caused by the mirror reflection of non affected hand may have led to the destabilization of the sensory cortices that changed the participants’ intention, meaning, and perception, thereby improving the subject’s motor control.