Mirror Therapy in Older Adults Post-stroke

Objective: The present work was carried out to determine the effectiveness of neuromuscular stimulation triggered by mirror therapy in older patients with post-stroke hemiplegia by two different intervention protocols, either intensively or spaced over time.

Design: Prospective longitudinal study Setting: Two Spanish rehabilitation centres. Participants: forty four aging patients (\>70 y) with diagnosed post-stroke hemiplegia were randomly distributed to intensive intervention group (5 times/week for 6 weeks), or to spaced intervention group (3 times/week for 10 weeks) which were underwent to similar number of mirror therapy sessions (n=30).

Main outcome measures: Muscle strength and activity was measured at baseline and at the end of treatment. Functional ability was also evaluated.

INTRODUCTION:

Cerebral ischemia or intracranial haemorrhage are the main characteristics of cerebrovascular diseases like the stroke. The disruption of the functional neuronal integrity after a stroke can affect both motor and cognitive states. The most characteristic motor sequel of a stroke is hemiplegia, characterized by the loss of voluntary movement, muscle tone, and osteotendinous reflexes from the affected hemiparetic body.

Mirror therapy (MT) was born in the late 1990s and was initially used to treat "phantom limb" symptoms. More recently, the effectiveness of this therapy in motor rehabilitation on post-stroke hemiparetic limbs has been also described. Due to its low cost and simplicity, it has become one of the most widely used therapies. The purpose of the MT is to perform bilateral and synchronous movements with the non-paretic limb, creating an illusion of movement in the brain.

The effectiveness of MT on brain injury can be explained in three ways. First, mirror neurons can recognize an action and activate motor learning through imitation. Secondly, neurological damage from a stroke usually causes inflammation and oedema that interrupts the transmission of motor information. The illusion of movement created MT reawakens these motor pathways by reactivating them. Finally, after suffering a stroke, patients have a different degree of activity in their cerebral hemispheres, being much lower in the injured hemisphere. The performance of MT contributes to reducing this imbalance.

The MT is based on visual and somatosensory information that is processed in the central nervous system. The movements of the non-paretic limb reflected in the mirror create an illusion of normal movement of the affected limb. This neurophysiological phenomenon stimulates the same cortical areas that are active during movement observation (somatosensory cortex, premotor and primary motor cortex, supplementary motor area, cerebellum and basal ganglia). The mirror reflection leads to additional activation of the contralateral hemisphere to the perceived limb, producing an increase in the hemiparetic cortico-muscular excitability. However, despite its valuable role on patients with post-stroke hemiplegia, its effectiveness in older subjects has not been defined so clearly.

OBJECTIVE For all the above, the objective of the present study was to analyse the application and effectiveness of MT in older people (\>70 years), and to compare the benefits between an intensively applied (5 times/week) MT protocol and a more spaced over time (3 times/week) procedure.

METHODOLOGY Design and participants will be explained elsewhere. Main outcome measures are muscle activity after intervention.

EXPECTED OUTCOMES We expect that all groups improved their muscle mobility and activity. Our data will confirm what intervention is more effective.

Eligibility Criteria:
Inclusion criteria:

* Voluntary aging patients (70-85 years-old) with ischaemic stroke diagnosed by imaging (CT or MR)
* To be included into physiotherapy therapy between two and six weeks after the stroke (mean of 20 ± 2 days)
* Brain damage and a significant limitation of hand extension and foot dorsiflexion stroke-derived without spasticity (Ashworth scale 1 or 1+).

Exclusion Criteria:

* Patients with haemorrhagic stroke
* With a surface EMG signal \<0.5 μV
* With previous neurologic comorbidity which comprise muscle strength
* Patients with medical treatment which may affect muscle strength
* Patients with pacemaker
* Those with severe psychiatric conditions like cognitive decline or dementia (beyond the aging-related degenerative progression).