New Zealand
Perspectives of motor recovery
after stroke
Winston Byblow
The University of Auckland
Movement Neuroscience Laboratory
Dept of Sport & Exercise Science
Centre for Brain Research, University of Auckland
Winston Byblow
Movement Neuroscience Laboratory
Department of Sport & Exercise Science
Centre for Brain Research
University of Auckland
Saturday, 7 September 13
A Centre for
Neurorehabilitation @ UCLP
Lecture
Tuesday 3th September
Gilliat Lecture Theatre,
Queen Square House, London
Part 1
Predicting motor recovery
• Accurate prognosis allows
– Personalised rehabilitation planning
– Stratification in clinical trials
• But it’s difficult for individual patients
Saturday, 7 September 13
ARAT = Action
Research Arm Test
Clinical assessment
Patients with
identical scores
at 2w may have
very different
outcomes. Their
potential for
recovery is
uncertain and
may go
unrecognised
Saturday, 7 September 13
Predict REcovery Potential
Predicted recovery of
upper-limb function
72 hours
SAFE score
≥8
Complete
MEP present
Notable
Asymmetry
index < PNR
Limited
Asymmetry
index > PNR
None
<8
5 days
TMS
MEP absent
10 days
Saturday, 7 September 13
MRI
12 weeks
Procedure
• Participants stratified according to the PREP
algorithm
• Upper limb function assessed with the Action
Research Arm Test by blinded assessors
– 2 weeks
– 6 weeks
– 12 weeks
– 26 weeks
• Upper limb therapy delivered 5/7 for 4 weeks
by blinded therapists
Saturday, 7 September 13
Main effect of prognosis on
ARAT at 12w
F(3,36) = 44.29, P < 0.0001
Saturday, 7 September 13
Potential benefits of using PREP
• Efficiency and economy
• Individualised rehabilitation planning based on
residual connectivity in key motor pathways
– Identify patients with potential for recovery that might
otherwise go unrecognised
• Stratification in clinical trials
Saturday, 7 September 13
Part 2
Noninvasive brain stimulation (NBS)
as an adjuvant to therapy
Is it as simple as
“turning the bad
side up, and the
good side down”?
Ipsilesional
Contralesional
Rebalancing M1 excitability is associated with better motor outcomes
Traversa et al. 1998, Stinear et al. 2008, Di Lazzaro et al. 2010
Saturday, 7 September 13
Non-paretic
PD
Paretic Hand
PD
Grip
McDonnell et al., 2006
TEST
Load
PF
Higher preload
force (PF)
Longer preload
duration (PD)
Preload duration
- improved with practice when primed
with iTBS and cTBS
Saturday, 7 September 13
Hand-Arm Function (ARAT)
– unchanged after iTBS and sham TBS
– decreased after cTBS, 46 to 41, p = 0.024
iTBS
cTBS
Saturday, 7 September 13
Implications
• Task-specific benefits of TBS primed
training
Expected: iTBS increased ipsilesional M1 excitability
• Temporary decline in upper limb function
after contralesional cTBS
Unexpected: cTBS decreased ipsilesional M1 excitability
Saturday, 7 September 13
Robbing Peter to pay Paul?
• Fallacy: What’s good for the hand, is good for the arm
• NBS investigated mainly with contralateral distal hand
(MEP)
• NBS also affects ipsilateral arm Bradnam et al., 2010,2011
• NBS modulates neurons forming cortico-reticulopropriospinal pathways
Would NIBS affect ONLY
the red structures?
(It seems unlikely).
image courtesy of Tim Verstynen
Saturday, 7 September 13
After c-tDCS is paretic
biceps brachii recruited
more efficiently for the task?
Yes
X
N= 12,
subcortical
stroke
(> 3 months)
R2 = 0.59, P = 0.003
SR= selectivity ratio
No
FM = Fugl-Meyer
Assessment
It depends on the individual’s impairment
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NBS to suppress Contralesional M1?
It’s not “one size fits all”
But with a suitable model, can
tailor to patient sub-type
Saturday, 7 September 13
Part 3
Stroke Rehabilitation
no lack of RCTs
no lack of evidence
no lack of guidelines
Do guidelines reflect the evidence?
No. Teasell 2012
Does the evidence reflect (clinical) reality?
Saturday, 7 September 13
Saturday, 7 September 13
The evidence base
for stroke rehabilitation
The total number of patients
studied in good quality motor
rehabilitation RCTs conducted early
after stroke and with positive
outcomes is vanishingly small not
very large...
Is that it?!
Why we should conduct more RCTs at sub-acute stage...
- interact with biological processes that promote spontaneous
recovery and plasticity
- break down the barriers of implementation
- strengthen the guidelines
Saturday, 7 September 13
Bilateral priming
Mirror symmetric Device allows user to make repetitive mirror
symmetric wrist flexion - extension with little effort / resistance.
Active - Passive. If one side is weak, mirror symmetric
movements are made by actively moving the good hand only.
Priming After 1200 repetitions, passive ECR & FCR MEP
amplitude increases by 30-40% for at least 30 mins afterward.
Rate of motor skill learning can be enhanced.
APBP = Active Passive Bilateral Priming
% change in FM score
30.0
Better
Primed
Therapy
22.5
15%
15.0
10%
5%
7.5
0
Therapy
-7.5
Baseline 1
Baseline 2Immediately After
One
Month Later
Before
After
1 month
Bilateral priming enhances
effects of motor practice
at chronic stage.
Saturday, 7 September 13
Bilateral Priming Accelerates
Upper Limb Recovery after Stroke
Stinear, Petoe, Anwar, Barber & Byblow. ISC & WCN, 2013.
• single centre RCT, blinded
therapists and assessors
• bilateral vs control primed therapy
• 51 of 57 completed to primary end point
• primed were 3x more likely to achieve
recovery plateau on ARAT by 12 w
ITT: OR 3.2; CI 1.1 - 10.7
PP: OR 3.5; CI 1.0 - 12.6
• more primed than control reached
plateau on ARAT by 12 w
Weeks
Saturday, 7 September 13
Conclusion
• Better prognosis
– help patients and therapists set
goals and realistic expectations
when rehabilitation begins
Saturday, 7 September 13
• Priming the brain
– not always one-size fits all
– a collection of adjuvant
techniques that can be
tailored based on patient
subtypes
Acknowledgements
University of Auckland
Cathy Stinear, Suzanne Ackerley, Alan Barber
Flinders University
Lynley Bradnam
Bionics Institute
Matt Petoe
Auckland District Health Board
Yvette Baker, Claudia Barclay, Patricia
Bennett, Jemma Crowe, Alison Elston, MarieClaire Smith, Anne Ronaldson, and Anna Vette
Questions or Comments? w.byblow@auckland.ac.nz
Saturday, 7 September 13