The question would be one of "plateau" on what?

Intrinsic frecovery should rely upon biological recovery, which is probaly limited in tim (say, 6-mo after stroke). Yet, there is ALWAYS time for adaptive recovery (e.g sensory "reweighting" across impaired and unaffected senses) and symptomatic revovery (e.g muscle strenghtening; treatment of spasticity etc.). Also, the interplay between biology and behaviour is not a one-way road, as it is often conceived. "Adaptive-behavioural" solutions (e.g. exercise, use of prosthesis etc) of course have a counterpart in neural rewiring: which is the egg an which is the chicken?.

Unfortunately, there is a trend for considering "true recovery" only as a synonym for "regeneration": the latter would be a welcome option, but not an obligation. After all, we all irreversibly lose neurons and muscle fibers (and many other biological components) every day: is life a continuous progression towards disability with no "recovery"?

Article The good-hearted and the clever: Clinical medicine at the bo...

Thank you Dr Tesio for your answer and publication. You gave me a lot to think about and I will read it carefully! At first, my question concerned the recovery plateau as a time (like you said around 6 months post-stroke) after which the patient won't improve further its function despite intensive rehabilitation (I was thus talking about functional recovery). The rationale underlying this concept (rationale that is explained to the patients and frequently used to discharge the patients) is that the brain cannot undergo further plasticity. One group proposed in 2004 that such recovery plateau may be a result of insufficient adjustment of the treatment's parameters (e.g. intensity) and lack of effective interventions (see attachment). I was just interested to know if such concept is shared by the scientific community.

Your answer widened the topic (which is great) to have a better understanding (and use) of the term 'recovery'. It should have been specified more clearly in my question...

Also, I wonder if we can say that all kind of recovery (biological, functional, adaptative, compensative...) implies at least some sort of brain plasticity (not only limited to sensorimotor cortices, but also to areas implicated in behavior/cognition ...) ?

I substantiallyagree with the nice Page's paper, but its perspective needs to be widened.

Two reflections:

1.By definition behaviour always has a "bio-neural" counterpart, not necessarily detectable (suppose many brain areas are better connected, with no single area reacheng the thtershold for our detection): the old mind-body problem! Beware of "tautologic" research, however, showing gorgeous brain images (fMRI, MEP mapping etc.) associated to some behaviour: the causal relationship remains hypothetical; association is required, not sufficient, for cause&effect conclusions. No appreciable biological changes=no appreciable recovery is a wrong equation.

2. Again, think to what a "plateau" is. All biological phenomena tend to "saturate" (floor-ceiling effect). When you walk near 6-7 Km/hr, your stride length can no longer increase, your step frequency meets muscular power limits, and you start running. A "plateau" is nothing else than a hidden improvement or at best a qualitative change you are no longer able to measure or detect through your instrument. For instance, if you look at "disability" in term of independence in daily activities, it shows a "plateau" when, say, you're becoming independent negotiating stairs (e.g. motor FIM scores approach 91). But a back pain patient may be "disabled" even if he/she's fully indpendent in daily activities. Suppose he cannot drive for more than 2 years or, he/she must abandon tiring job. Using the "performance" meter, rather than the "independence" meter, you "straighten up" the "plateau" and you can go on along your variable. The issue now becomes one of "is that improvement worth?" (for instance, back pain treatment would not be worth an expensive inpatient stay). Now, take upper limb function or aphasia 1 year after stroke. Does recovery ever reach a "plateau" or, we are simply deciding that the expected further recovery is not worth the efforts required to achieve it? Also, is a slowing of secondary/tertiary impairments (pain. spasticity/contracture, depression etc.) a form "recovery" or, do we make "recovery" a synonym for "positive change"?

Scientists should not conceal decisions under measurements: these are related, yet distinct concepts.

Just some ideas, before too an automatic response is looked for to your seminal question.

Regards

LT

Thank you again for your reflections and interest for this topic.

Here is a résumé of the discussed ideas:

1. A "real" plateau of change may be the result of various factors, such as insufficient adjustment of parameters or lack of effective interventions or a limited intrinsic capacity of the biological system to adapt further.

2. A "false" plateau of change may be the result of undetected changes by the measurement tools used.

3. Trying to refute the concept of a recovery plateau is maybe irrelevant for clinicians, because at some point trying to improve further a performance with intensive treatments is not necessarily a good decision for the patient's quality of life and cost-effectiveness of rehabilitation (expensive inpatient care).

Concerning the third point I would like to add something based on my (very limited) experience. The words that we use as therapists may have a great impact on the patient's perception of its condition and future. Of course, some patients understand well that they will have to cope with their chronic disabilities and redefine their role in society. Others will train/practice for years after the stroke, always looking for new interventions, in order to completely recover. And some patients just give up, even during subacute care, and the risk of a depression is very real. Knowing that a debate exists concerning the biological concept of a plateau of recovery, would it be better to choose the words carefully when discussing such concept with the patient and its family ? I mean, they need to be prepared to live with their disabilities, but I'm not convinced that they should be discouraged to push themselves even after rehab. So often we hear the stories of patients that were told they will never walk again, and finally prove it wrong. Or maybe it's just my optimistic nature ...

Plateaus of recovery after stroke are generally considered to be evident approximately 3 months after stroke. There are many factors that contribute to these plateaus or limits on recovery. For example, a very large stroke or one strategically placed will undoubtedly be a limiting factor. However, for those of us who approach recovery from a neuroplasticity perspective we see evidence of recovery continuing for years. A good example of this is constraint induced movement therapy or patients who have the means and motivation to follow very intensive programs of multi-modal rehabilitation on their own which results in on-going recovery. An important consideration is that therapy is often limited in duration (for pragmatic reasons) and in addition may be delayed so as not to optimally engage the brain's intrinsic repair processes (e.g. up-regulation of growth factors, etc). As a result the "apparent" plateau may be due largely to the type of therapy provided which is often not driven by scientific evidence. A nice example of this concerns upper limb deficits. The amount of reaching practice achieved in typical therapy sessions is often only 30 or 35 reaches. What is this based on? Is 35 reaches optimal? What if a much higher threshold of reaching is required for recovery to occur. Clinically relevant animal studies and mathematical model suggest that much higher levels of reaching are required to achieve recovery. I have appended a recent review article that discusses some of these issues.

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I do agree with Dale's answer. Hospitals usually discharge patients from rehabilitation 6 months after a brain injury (apart of stroke). The rationale for it is only, in my opinion, the lack of human resources for attending the high number of people with neurological injuries. However good results can be achieved even years after this putative plateau has been reached. This is our experience. Reasons for it? adult neurogenesis and neuroplasticity.

one more paper denying relationships between brain lesion volume and upper limb impairment in patients with chronic stroke [5 years before evaluation]: Page SJ & Coll in Archives of Physical Medicine & Rehabilitation 2013; 94: 817-21

thanks to everybody for these hints & comments, Mauro

Wow, some very esteemed stroke scientists answering this question! Dr. Tesio's question-- "plateau on what?" is very relevant here. I think a distinction needs to be made between biological recovery and adaption and the value of enriched environments. Lisa Salisbury talks about those outliers-- the survivors that do well despite poor prognosis, "Some carers recalled being informed that their relative would require nursing home care; this was without prior consultation and contrary to guideline recommendations(Scottish Intercollegiate Guidelines Network 2002). In each situation, the carer rejected this suggestion and chose to take their relative home. Interestingly, by the time of interview, all patients were walking independently and living at home." (Salisbury et al., 2010, p. 430).

What accounts for these remarkable results-- is it recovery or adaptation? Dr. Corbett's animal research clearly points to the benefits of an enriched environment.

In stroke, there is an emphasis on aggregated data. Perhaps a little more theorizing and the examination of diversity might provide different answers about plateaus. Stroke was once regarded as untreatable, but the research clearly demonstrates that rehabilitation does assist recovery. Perhaps it is time to understand more about enriched environments after discharge from formal services.

As noted, your definition of "recovery" is important. Is it neurological recovery or functional recovery? Motor recovery of upper limb? lower limb? or is it some other domain? I think that it's generally accepted that neurological and functional recovery "plateau" at ~ 6 months, given the usual interventions that are employed in traditional stroke rehabilitation While the potential for recovery is not limitless, it is clear that newer interventions can enhance functional outcomes and the optimization of stroke rehabilitation is still an evolving process. You might like to take a look at a recent review by Ganguly in the Annals of Neurology, to get a sense of challenges that need to be addressed as the recovery plateau inches closer to best possible restoration of function.

Hi Dr Abrams,

In hindsight, I think I was talking about functional recovery. But as discussed with Dr Tesio, any kind of recovery should imply at least some sort of cerebral adaptation that can't be always detected. Thus maybe my question could be adapted to any kind of recovery that are deemed to present a plateau of change.

I agree that the potentiel for any kind of recovery after a SNC lesion is not limitless, but as you pointed out such plateau around 6 months is generally accepted given the outcomes in rehab. I wonder if some studies really tested this concept, before being 'generally accepted'?

Thank you for the reference, I'll read it carefully !

Cheers

P.S. Thank you to all that have participated so far in this topic, it really widened my understanding of the concept of recovery !

Steven Faux University of NSW

I agree that plateau is more a reflection of local resources, than a patient and their brain's capacity for further recovery. In a study by teasell and in our research we have noted great disparity between resources in different settings - metropolitan rural and remote. teasell found that length of saty in in patient rehabilitation post stroke was associated with the availability of outpatient services which had a impact on the concept of plateau - where outpatient services are present plateau was less likely to be identified in inpatient settings and naturally more common in outpatient settings. From an experiential point of view - plateau is a misnomer and can be considered nihilistic or worse still an assault on the patients self confidence. Nursing Home placement is not the corollary to plateau but simply acknowledgment that the person needs supported accomodation to continue to achieve any further functional gains. ASrguments put by Page regarding further impovements in function in the chronic stages of stroke go towards a need to reexamine the concept - it value to the patient and its implication for resources.

Article Stroke Rehab Down Under: Can Rupert Murdoch, Crocodile Dunde...

Thank you Dr Faux for sharing such an interesting analysis (and original title!) of how discrepancies in stroke rehab services in a whole country (metropolitan vs rural vs remote) can affect recovery. It reminds us that we cannot fully attribute a patient's plateau of recovery only on the basis that the biological system reached its full potential: it can also be ''our fault'' in terms of insufficient services and resources.

Also, I'm curious concerning the Aboriginal people in Australia. In my country (Canada) there are about 1 million natives, which represent 3,7% of the whole population. According to the canadian hearth and stroke foundation, they have a 1,5 - 2 X higher risk of developping a heath disease and suffering a stroke. It can be explained by a higher prevalence of physical inactivity, smoking, overweight, obesity, high blood pressure and diabetes. They also present lower socioeconomic status which is associated with various risk factors of health disease. Because they often live in remote locations they face very high rates of food insecurity due to the high price, low quality and limited availability of fresh, healthy and nutritious foods. Finally they do not have the same access to health care services. I wonder if the picture is similar in Australia ?

Cheers

I will add to this discussion and say simply that I don't think there is great evidence that we reach plateau with many patients with stroke, no matter the severity. Several previous responders allude to some realities: a lack of resources (facility, clinicians) to provide care, discharge that must happen from hospital at some point in time, lack of reimbursement for care (what happens often in the US) leading to disparities, and identifying the optimal window of opportunity to capitalize on brain plasticity. There is evidence that continuing to dose patients with chronic stroke can lead to meaningful functional improvement, which others have included in their responses (CIMT). I would like to add other papers which provide evidence of improvements without such intense and focused interventions. I present 2: 1.) Pereira, et. al., FES for improving gait in persons with chronic stroke, Topics in Stroke Rehab, 2012.; 2.) Balance and balance self efficacy are associated with activity and participation after stroke: a cross-sectional study in people with chronic stroke. Archives of Phys med rehabil, 2012.

Some may argue that diminishing returns outweigh the cost of providing skilled care to patients with chronic stroke, but I think argument diverts from the real question. More therapy can improve function in those with chronic stroke, we don't know the appropriate dose, timing or intensity. We don't know how functional we can get people because of the barriers to receiving therapy or continuing therapy.

If by plateau you mean a leveling off of natural recovery, it is an undisputed fact. After 6 months spontaneous improvement is over for all but the very rare outlier (Wade et al, 1983; Sunderland et al, 1989; Jorgensen et al, 1995). That does not mean that focused interventions of adequate intensity, frequency, and duration cannot have a positive effect for some individuals. The question becomes, how big is the effect and is it worth the investment? Many patients are incredibly inactive after stroke (Zalewski & Dvorak, 2011; Britton et al, 2008). For these patients disciplined activity can certainly be health promoting.

Professor Bohannon, its a pleasure read your comments - indeed I agree with you, about how big is the effect e would be worth the investiment in a rehabilitation program? However, I believe that in the first 6 months ,all efforts should be done to get the best response to patients, whould you agree with me? Regards,

for sure, first 6 months are crucial; yet, further possibilities still exist: in the alleged paper [Arch Phys Med Rehabil vol 81, April 2000, pagg. 379-388], an old experience of valuable intervention on apraxia is reported whose patients were all in a chronic phase of illness (more than 5 months from stroke onset), whilst 3 out of 7 controls were tested 2 months after stroke onset. That would have weakened statistical results, if spontaneous recovery was more important than rehabilitative experimental treatment, by Smania & Coll..

Best regards, Mauro Colombo

Functional recovery in stroke survivors is very rapid within the first 3 months after stroke during which there is both neurological and motor recovery. This is also followed by another spike in the recovery in the next 3 months (4-6 months post-stroke) during which the recovery is mostly motor. After this period to 12-month post-stroke, there is clinical improvement in the functional recovery but not statistically significant from what occurs at 6-month. After 12-month, there is majorly functional drift which impact on the societal integration of the stroke survivors. The initial recovery is as a result of reduction in the intra-cranial pressure resulting in the recovery and savaging of the pre-umbra areas. This is what results in the neurological recovery. The functional performance recovery is due to repetition and frequency of performance which causes the drift in the functional topography in the brain (neuroplasticity). This neuroplasticity is mostly observable within the first 6-month but still continues to one year or a little more after the stroke.

Recovery to stroke survivors and their families is a return to personally meaningful roles and activities. Some of the recovery to meaningful activities will be from functional recovery, but other "recovery" likely needs to come from adaptation. Even in the smallest strokes, those with little physical impairment, survivors and their families are challenged to adapt to small changes. Symptoms like fatigue, finger clumsiness, or minor cognitive slowness are devastating for some people.

I think we need to draw on other theoretical lens than biology to understand plateaus and "recovery" after stroke. Stroke is sudden, and so the impairments are put into sharp relief against the backdrop of " I was". In fact there are gains and losses throughout life.

Paul Baltes uses the story of Arthur Rubinstein that I think may be a model for understanding "recovery" in stroke:

When the concert pianist Arthur Rubinstein, as an 80-year-old, was asked in a television interview how he managed to maintain such a high level of expert piano playing, he hinted at the coordination of three strategies.

First, he played fewer pieces (selection); he practiced these pieces more often (optimization); and to counteract his loss in mechanical speed he now used a kind of impression management, such as playing more slowly before fast segments to make the latter appear faster (compensation).

The full article on Selection, Optimization, and Compensation Theory is online

http://www.mpib-berlin.mpg.de/volltexte/institut/dok/full/Baltes/onthein/index.htm

This is a very interesting article that, as you say, may help clinicians and researchers to better understand how motor learning can be optimized using evidences from cognitive sciences.

thank you Sharon for the hints & for the story of Arthur Rubinstein: I remenber him cheerfully, Mauro

Fantastic Sharon and very useful. Thank you. Jesús

As I explained in my previous response, the recovery in stroke survivors is very rapid within the first 3 months with a spike in the recovery in the 4-6 months post-stroke and a clinically significant but statistically insignificant improvement to 12-month (Gbiri CA and Akinpelu AO. Pattern of Post-stroke Functional Recovery among Nigerian Stroke Survivors in the First 12 Months. Nigerian Quarterly Journal of Hospital Medicine 2011; 21(3):245-248 ). We need to still continue to work on stroke patients even after the 6-month rapid recovery in order to improve their quality of life (Gbiri CA, Akinpelu AO. Quality of life of Nigerian stroke survivors during first 12 months post-stroke. Hong Kong Journal of Physiotherapy.2012;30(8): 18-24). We should realise that our ultimate goal is to return the stroke survivor to as near their pre-morbid state as possible or to improve their functional performance towards reduction in activity limitation and participation restriction. Then, if you ask me whether it worth investing on, I will definitely say yes.

I am a only neuroradiologist.

I can present You two papers from the Stroke and Rehabilitation Units of our Department

Cioncoloni D, Martini G, Piu P, Taddei S, Acampa M, Guideri F, Tassi R, Mazzocchio R. Predictors of long-term recovery in complex activities of daily living before discharge from the stroke unit. NeuroRehabilitation. 2013;33(2):217-23

Cioncoloni D, Piu P, Tassi R, Acampa M, Guideri F, Taddei S, Bielli S, Martini G, Mazzocchio R. Relationship between the modified Rankin Scale and the Barthel

Index in the process of functional recovery after stroke. NeuroRehabilitation. 2012;30(4):315-22.

Best regards,

Alfonso

kinD Alfonso Cerase,

both papers underscore the role of Barthel Index

best regards, Mauro Colombo