INVESTIGATION OF CLINICAL FEATURES AND NEURAL SUBSTRATES UNDERPINNING UPPER LIMB IMPAIRMENT AND RECOVERY OF VOLUNTARY MOTOR BEHAVIOUR, AFTER STROKE

Prognosis of recovery has always covered an important role in medicine, due to its relevance for monitoring and interpreting patients’ achievements over time. According to Hippocrates, prognosis is a way of interpreting life as a continuum along the past, the present and the future, and not only as a sample of data points. After stroke, clinicians, patients and caregivers always ask what is likely to be expected for their clinical conditions and life in the future, and what the best therapeutic options might be for them. Medicine has always tried to answer these questions through studies on factors able to forecast the future, considering the path of spontaneous neurological recovery. Even research in rehabilitation has always attempted to predict motor recovery by studies assessing and measuring functional aspects of movement. What is missing so far, is that we do not know how rehabilitation interventions may change the pattern of recovery after stroke, causing uncertainty on the potential of recovery of each patient, in response to specific interventions. In this perspective, being familiar with interpreting initial signs and symptoms, selecting the most appropriate assessment strategy and using prediction models is pivotal to be timely and clinically efficient. Within this framework, we faced the important terminological issue of the concepts of Prognosis and Prediction. Prognosis, indeed, refers to the expected outcome in absence of intervention, while Prediction refers to the expected outcome in response to rehabilitation. Moreover, it is now widely accepted that patients are underdosed and do not receive enough rehabilitation. With the aim of introducing a novel concept of prediction, focused on the expected recovery in response to rehabilitation rather than spontaneous recovery, we have conducted a series of studies (i.e. systematic review, retrospective and longitudinal studies) designed to identify potential predictive factors and investigate the impact of different doses and modalities of therapy. In particular, we found that factors known as predictive (e.g. age, muscle strength) of spontaneous upper limb (UL) motor recovery do not predict rehabilitation-induced recovery, in subacute and chronic stroke survivors. Indeed, UL motor recovery is associated with brain lesion characteristics, genetic features and residual attentive and motor function at baseline. Moreover, higher dose of treatment leads to higher motor response, with different effect according to the type and doses of intervention. However, implementation of robust and agreed methodologies for the development of prognostic studies in rehabilitation should be implemented.