Motor Recovery of the Severely Impaired Paretic Upper Limb After Mirror Therapy in Sub-acute Stroke

It was reported that upper limb hemiparesis happened in 80% of stroke patients and only 20% regained full arm function 6 months post stroke. The paretic upper arm accounted for 50% of the variance in functional limitation after stroke. Early and intensive upper limb intervention can promote motor recovery of paretic arm and is associated with better upper limb functional outcomes on 6 month post stroke. Mirror therapy (MT) is one of the potential approach in enhancing motor recovery of paretic arm after stroke. However, the effect of intensive MT on the motor recovery of severely impaired paretic arm after stroke has not been investigated. Knowledge on the effect of intensive MT on motor recovery can enhance formulation of effective and efficiency treatment protocol in stroke rehabilitation. Therefore, our study aims at investigating the effect of intensive MT on the motor recovery of severely impaired paretic arm of patients at subacute phase of stroke.

Stroke patients admitted to Haven of Hope Hospital will be screened according to inclusion and exclusion criteria. Eligible subjects will consent and be randomized into two groups: MT group- subjects will have daily two 30-min sessions of standardized bilateral upper limbs exercise with presence of mirror, 5 days per week for 4 consecutive weeks. During MT, a mirror is placed in the patient's mid-sagittal plane, with the reflecting surface facing the non-paretic upper limb so that the reflected image of this non-paretic limb would be perceived as the paretic upper limb. Subjects are instructed to watch at the movements of the reflected image of the non-paretic limbs and at the same time, the paretic upper limb should imitate the observed movements and be synchronized with those of the good side. Standardized bilateral upper limbs exercise (4 sets of 30 repetitions of shoulder, elbow, wrist and fingers movements) will be carried out within 30 min per session. Control group subjects will receive same daily two sessions of standardized bilateral upper limbs exercise without mirror, 5 days per week for 4 consecutive weeks. Motor functions of paretic arm of subjects measured by Fugl-Meyer Assessment (motor domain) and Wolf Motor Function Test will be assessed by independent assessor who is blinded to the group allocation of subjects before and after the 4-week intervention. Baseline comparison between the two groups was tested with independent t-test and the difference among and between groups after intervention will be tested by repeated measures ANOVA with level of significant at 0.05.

Inclusion criteria

• age 35 years or older
• first stroke within the first month after stroke onset;
• has upper limb paresis contralateral to the side of cerebral hemisphere with stroke;
• Presence of active movements (at least flicker of movement in gravity free position, but not able to accomplish full range of motion against gravity) at any one joint of shoulder, elbow and hand of hemiplegic arm, and Motricity Index less than 47.
• Able to follow instructions

Exclusion criteria

• has visual impairment not correctable by corrective lens;
• has cognitive impairment (Mini-Mental State Examination score < 22/30)
• has comprehension or expression aphasia;
• Presence of visuospatial neglect
• has premorbid neurological or musculoskeletal conditions that affect movements in the upper limbs