Lycra Orthosis as Therapy for the Upper Limb After Stroke

Introduction:

Stroke causes complex adult disability, with 30-50% of survivors experiencing limited independence in daily activities. Annually in Scotland there are around 14 000 new stroke events and approximately 80,000 survivors living with stroke related disability.This number will increase by 2035 as demographic change leads to a 26% increase in people aged over 65 years and developments in acute stroke care lead to improved stroke survival rates. Consequently, the cumulative cost to the UK economy of stroke, currently estimated to be £8.9 billion, will increase proportionately.

Poor upper limb (UL) recovery is a major cause of post-stroke disability with fewer than 15% of survivors regaining full function by 6 months. Activities found difficult by stroke survivors include dressing, bathing and feeding where good UL and hand function is required. Limited UL function is characterised by muscle weakness, muscle stiffness or spasticity and altered sensation leading to loss of movement co-ordination for functional tasks. UL impairment is also an important predictor of quality of life six months after stroke onset. It is therefore vital for quality of life and independent functioning after stroke that effective strategies to improve arm recovery are found.

Background:

Despite the problem of poor UL recovery, few cost-effective rehabilitation interventions are available. Intensive repetitive functional task-specific practice is effective at improving UL recovery, particularly where the unaffected UL is constrained to force practice with the affected UL. However effects depend on six hours per day of intensive physiotherapy to guide practice, combined with constraint in a mitt of an additional 8 hours per day. Such intensive supervision although effective, is unfeasible in many healthcare settings, and survivors and therapists express reluctance to participate in such demanding treatments. It is therefore essential to develop effective, resource efficient ways to provide survivors with therapeutic correction of movement during task practice, but with less therapy supervision. This is vital because rehabilitation therapy available within stroke units in the UK is typically less than one hour per day.

Dynamic lycra orthoses (DLO) may provide an inexpensive (£200 per unit) and potentially effective adjunct to UL rehabilitation after stroke. The orthoses correct limb position during movement and provide sensory feedback, as therapists would normally do. They are made to measure fabric lycra compression garments individually tailored to correct UL movement and positioning. They do this by providing correction of finger, wrist and elbow movement whilst still allowing functional movement. The orthoses can be worn during therapy and throughout the day when practising and performing functional tasks.

Theoretically, viscoelastic properties of the DLO create biomechanical forces for joint stability and functional positioning where muscle weakness is problematic. The DLO may also stretch stiff or spastic muscles where they limit functional UL use. Finally, pressure exerted by the garment on muscles and skin may stimulate sensory awareness and sensory feedback thereby improving neurophysiological control of movement. Because the DLO can be worn for long periods of time, it may optimise effects of task practice during formal therapy but also during self-directed task practice, without the need for direct therapy supervision. Indeed, a growing body of evidence shows that DLO wear reduces spasticity and improves UL movement and function in children with neurological impairments.

Rationale for the Study:

Although discussions with local stroke rehabilitation therapists suggest some DLO use in practice, evidence of effectiveness for UL outcomes following stroke is limited. Literature searches conducted by the investigators identified only one single case study showing improved dexterity, dressing and writing in a survivor with longstanding stroke after wearing the garment for 12 hours daily over 6 weeks. A second crossover trial with survivors (n=16) 3 to 36 weeks after stroke onset showed better wrist resting posture, passive range of movement and reduction of wrist and finger muscle spasticity after only 3 hours wear of the DLO. These studies were small and of low quality but suggest that evaluation of potential effectiveness of the intervention on UL impairment and activity limitation outcomes as an adjunct to UL rehabilitation after stroke is warranted.

Objectives

1. To assess the feasibility of conducting an effectiveness trial of the DLO in rehabilitation.
2. To assess the potential effectiveness of the DLO intervention provided as an adjunct to rehabilitation on: UL sensory and motor impairments, UL activity limitation, activities of daily living and quality of life compared to those receiving usual rehabilitation only in order to select a primary outcome measure and establish sample size for a full scale effectiveness trial.

Research Questions

1. What proportion of stroke survivors agree to participation and randomisation in the DLO study?
2. What proportion of participants who consent to participate in the trial fully complete the intervention and outcome and follow-up assessments?
3. What is the magnitude and direction of difference in upper limb impairment and activity in stroke survivors using the UL DLO intervention as an adjunct to rehabilitation, compared to those receiving standard rehabilitation?
4. Is there any evidence that effects of the orthosis are likely to persist at eight week follow-up?
5. Are there indications that responses to the DLO are likely to differ between participants depending on initial UL impairment severity and stroke type (lesion location, stroke classification and ischaemic or haemorrhagic)?

Design:

A randomised controlled feasibility trial to collect data to provide an estimate of the direction and magnitude of effects on a range of clinical outcome variables to determine the most appropriate primary outcome and sample size for a definitive trial. of particular importance is assessing which survivors may benefit most, according to severity of UL impairment.

Procedure:

51 stroke survivors consecutively admitted to Ninewells Hospital and PRI and their associated rehabilitation hospitals. Potentially eligible patients will be initially identified by nursing, rehabilitation staff or stroke research nurses between 2 and 4 weeks after admission to either of the selected acute stroke units, or when patients are medically stable. The nursing and rehabilitation staff will provide invitation letters signed by the care team and explain information sheets to patients about the study, with an invitation to participate. The study researchers will then approach patients who have indicated an interest in participation. Patients who agree after discussion with nurses and therapy staff to be considered for and screened for inclusion, will be approached by study researchers 24 hours after being given the information. The study will be explained in detail and written informed consent obtained before screening for inclusion criteria and for study participation.

Cognitive ability will be formally assessed using the Montreal Cognitive Assessment, communication will be assessed using the NIH Stroke Scale, scales used by this team in previous stroke studies. Upper limb activity limitation will be assessed using the Action Research Arm Test (the ARAT). The ARAT will determine upper limb severity (mild, moderate, severe) for purposive sampling purposes and to ensure equal severity sub-groups at each phase. Other screening information (confirmation of stroke type, previous stroke, ability to participate in rehabilitation, premorbid arm impairment, shoulder pain and sensitivity to lycra and information about comorbidities) will be obtained from medical records, from staff and from the patients themselves and recoded in a proforma format in the CRF. Written informed consent for medical record review will also be undertaken at time of recruitment.

Randomisation:

Investigators will randomly allocate participants within each severity sub-group to a control group or an intervention group on a 2:1 basis. This will lead to 33 participants (11 in each severity sub-group) receiving the lycra orthosis and 18 (6 in each severity sub-group) acting as control participants. After baseline assessment and, given that side of hemiplegia may determine participants characteristics, stratification will be undertaken according to side of hemiplegia using a secure, concealed web-based computerised randomisation system provided by Tayside Clinical Trials Unit.

Intervention Group:

Participants will be assessed and measured for the DLO by a study Occupational Therapist (OT) trained in DLO fitting. All participants will receive the sleeve orthosis, which encompasses fingers, wrist and elbow, tailored to their own requirements as assessed by the OT, who will be informed by participant performance on the baseline measures.

The OT will liaise with manufacturers and will order, fit and arrange for any adjustments to the orthosis to ensure fit.

Participants will be asked to wear the DLO eight hours per day for a maximum of 8 weeks during waking hours. The orthosis will be removed for washing and bathing, but otherwise participants will wear the DLO for participation in usual therapy as directed by the therapists, and daily activities.

Post Stroke upper limb oedema has been identified as a factor in early recovery. Participants in the intervention group, reporting oedema that prevents garment wear as per protocol, will be provided with an oedema glove to wear at night and information on oedema management as per normal care.

The study research therapists will review DLO wear after 4 weeks of full wear. In order to reflect normal practice, if issues arise at any other time the researchers will advise participants and key health professionals to contact them.

The treatment group will also receive usual care and rehabilitation and a general advice leaflet on looking after their arm

Control Group:

The control group will receive usual care and rehabilitation and a general advice leaflet on looking after their arm.

Both groups will continue to receive usual occupational and physiotherapy.

Healthcare Professionals: Regular therapists and nurses will record time for DLO application and type and duration of usual therapy using a simple proforma log.

Outcome assessment will be undertaken by a blinded assessor at baseline, after eight weeks of intervention with follow-up eight weeks after that.

The exploratory RCT will allow an estimation of effect size and variability which will facilitate a sample size calculation for a later definitive RCT to test effectiveness. The sample size of 51 is accepted as being adequate for a feasibility study of this type.