Effects of Using the Electrodress Mollii on Spasticity

Spasticity is a common manifestation of lesions of central motor pathways, such as after stroke, traumatic brain or spinal cord injury and in cerebral palsy and is associated with increased impairments and disabilities. Spasticity may be associated with pain and contractures, caused by muscle weakness, reduced muscle length and volume that add to the disability.Treatments of spasticity comprise physical therapy, pharmacological agents and surgical treatment. Recently, a systematic review concluded that transcutaneous, electric nerve stimulation may have beneficial effects on spasticity and activity performance after stroke, which lends support to the new treatment method Mollii, which will be evaluated in this study.The Mollii suit provides electric stimulation through multiple electrodes places in a tight fitting suit. This study relates to the clinical trials performed at the University department of rehabilitation medicine at Danderyd Hospital in Stockholm and comprises an initial study of effects on spasticity ("Mechanical substudy") and a following, exploratory treatment trial ("Clinical substudy") in patients with spasticity after stroke.

Spasticity is a common manifestation of lesions of central motor pathways, such as after stroke, traumatic brain or spinal cord injury and in cerebral palsy and is associated with increased impairments and disabilities. Spasticity may be associated with pain and contractures, caused by muscle weakness, reduced muscle length and volume that add to the disability.Treatments of spasticity comprise physical therapy, pharmacological agents and surgical treatment. Recently, a systematic review concluded that transcutaneous, electric nerve stimulation may have beneficial effects on spasticity and activity performance after stroke, which lends support to the new treatment method Mollii, which will be evaluated in this study.The Mollii method has been developed by Inervetions, which is a small Swedish med-tech company, and represents an innovative approach for non-invasive electro-stimulation to reduce spasticity and improve motor function. The theoretical background of this treatment method primarily refers to the concept of reciprocal inhibition, i.e. that sensory input from a muscle may inhibit the activation of an antagonistic muscle. Thus, the application of Mollii aims at stimulating a muscle, e.g. the anterior tibial muscle of the lower leg in order to reduce reflex mediated over-activity, i.e. spasticity, in calf muscles by inducing reciprocal inhibition.

Mechanism substudy: explorative single group design with three different stimulation paradigms provided to all participants by double blinded randomisation. Clinical substudy: explorative single group design.

Mechanism substudy: 3 trial sessions ( electrodes set to 1) 20 Hz, 2) 30 Hz, 3) 0 Hz (placebo). Patients and datacollectors were blinded in terms of the randomised order of the treatment at each of the 3 trial sessions ( electrodes set to 1) 20 Hz, 2) 30 Hz, 3) 0 Hz (placebo). Clinical substudy: Use of the fitted and individually set body suit, Mollii, in the home setting for 6 weeks

The Mollii method is provided in a tight fitting, whole body suit with multiple electrodes that can be set individually. The Mollii method uses low frequencies and low intensities that evokes sensory input but does not directly elicit muscle contractions. The theoretical background of this treatment method primarily refers to the concept of reciprocal inhibition, i.e. that sensory input from a muscle may inhibit the activation of an antagonistic muscle through the activation of the disynaptic reciprocal Ia inhibitory pathway.

Measure related to spasticity: The Neuroflexor device comprises a portable computer-controlled step motor system with a lever arm that generates constant velocity movements of the wrist or ankle. The passive resistive force of the wrist or ankle is recorded by a force transducer. The force is then analyzed off-line and the total resistance is separated into mechanical and a neural components using a neuro-biomechanical computerized model. NeuroFlexor neural component reflecting stretch reflex mediated resistance, represents the main outcome. The NeuroFlexor hand (used in mechanism and clinical substudy) and foot module (used in mechansim substudy only) is a valid method that quantifies and distinguishes the genuine spasticity and the mechanical contributions (viscoelastic and soft tissue components) of the resistance opposing a passive stretch.

Mechanism study: To assess change, NeuroFlexor data is recorded before, during and 10 minutes after treatment at each session. Clinical study: To assess change Neuroflexor data is collected before and after the 6 week intervention.

Measure related to spasticity: Surface electromyography (sEMG) signal of spastic muscles in the upper and lower limb (flexor carpi radialis, medial gastrocnemius and soleus muscles).

Clinical assessment of motor sensory function of the upper (min 0 p and max 126p) and lower extremity (min 0 p and max 86p). Max point indicates no detected impairment.

Self-perceived functioning and disability (min 0 p and max 100p/item). Max point indicate no perceived disability.

Inclusion Criteria: Eligible participants had suffered a stroke > 12 months earlier were living with hemiplegia affecting the right or the left side of the body including both upper and lower extremity function were able to walk with assistance or independently according to the Functional Ambulatory Categories (Holden 1984) with a score of 2-5 activity in upper extremity was limited according to the Action Research Arm test (ARAT) (Nordin 2014) but could perform a grasp and grip movement were > 17 years old, able to understand instructions as well as written and oral study information and could express informed consent Exclusion Criteria: no detected neural component exceeding the cut off for spasticity according to the Neuroflexor (> 3. 4 Newton) in the wrist flexors contractures not compatible with performing the Neurofexor test or walking any other disorder with an impact on sensorimotor function any other severe concomitant disease (such as cancer, cardiovascular, inflammatory or psychiatric disease), uncontrolled epilepsy or blood pressure, major surgery during the last year, any implanted medical devices pregnancy BMI>35

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