Patient and public involvement in pragmatic trials : online survey of corresponding authors of published trials

Acknowledgements The authors acknowledge Dr. Paxton Montgomery Moon, Alison Howie, Hayden Nix and Dr. Merrick Zwarenstein for their contributions to the data extraction. They also thank Drs. Bruno Giraudeau and Agnes Caille (University of Tours), Dr. Laura Hanson (University of North Carolina School of Medicine) and Dr. Jill Harrison (Brown University) for assistance with pilot testing of the survey questionnaire. Funding: This work was supported by the Canadian Institutes of Health Research through the Project Grant competition (competitive, peer-reviewed), award number PJT-153045, and the National Institute of Aging ( NIA) of the National Institutes of Health under Award Number U54AG063546, which funds NIA Imbedded Pragmatic Alzheimer’s Disease and Related Dementias Clinical Trials Collaboratory ( NIA IMPACT Collaboratory). The funders had no role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the article for publication.Peer reviewedPublisher PD

Exploring Functional Neuroplasticity and the Associations with Outcomes of Advanced Gross Motor Interventions for Children with Cerebral Palsy

Improvement of advanced gross motor skills is a key rehabilitation goal of children with cerebral palsy (CP), given their underlying brain injury, motor impairments, and physical activity participation possibilities. Evidence for potential functional neuroplastic change following gross motor training is lacking, and may provide important indicators that could advance intervention design to target children’s goals. This research focused on independently ambulatory children with hemiplegic CP (HCP) (i.e., those with unilateral motor involvement), and with diplegic CP (DCP) (i.e., those with both legs involved). In the first study, an ankle dorsiflexion functional magnetic resonance imaging (fMRI) paradigm was refined and optimized to calculate the ratio of hemispheric activity in the primary motor cortex (M1) and overall M1 activation volume. This fMRI paradigm was then used in two linked studies that explored relationships between changes in M1 activation and changes in advanced motor skills following goal-directed gross motor interventions for children with HCP and DCP. Lower limb M1 functional connectivity was also probed using resting state fMRI. Individual changes in fMRI outcomes were observed, with no significant group change. Three patterns of change in the laterality of M1 activation were identified: maintenance of principally contralateral activation (i.e. typical motor control), increased contralateral activation, or increased ipsilateral activation. Relationships were observed between motor skill gains and M1 activation during ankle dorsiflexion on the more affected/non-dominant side. For children with DCP, increased ipsilateral activity was associated with motor skill improvements. In both HCP and DCP, a smaller cortical activation volume was a predictor of motor skill gains. These exploratory findings suggest that M1 activation may be related to motor skill change. This investigation of lower limb functional neuroplasticity is an important step towards developing evidence of the underlying neural mechanisms of advanced gross motor skill improvement following interventions for children with CP.Ph.D

Reference frames for reaching modify the interaction between modes of postural control

When standing, feedforward (FF) activity is produced in the supporting limbs prior to arm reaching movements and provides the biomechanical conditions required for reaching the target. When balance is unexpectedly perturbed, for example by a sudden support surface movement, short and long feedback-based (FB) postural responses are produced which restore body position to its pre-perturbation state. How these 2 modes (FF and FB) interact however, remains unclear. We investigated this relationship by examining if the FB-based automatic postural reactions (APR) evoked during reaching on a moving platform are modulated differently if the target moves with the body (an egocentric target, EGO), rather than moving independently of the body (EXO target). Furthermore, we varied the perturbation onset to occur either in the acceleration (RPa) or deceleration phase (RPd) of the reach. Analysis of EMG activity revealed that short latency APRs were reduced across both RP conditions with respect to P, and long latency APRs were significantly reduced. The reduction in the long-latency phase of the APRs was greater in RPd conditions than RPa, suggesting that perturbations during the acceleration phase of the reach are highly disruptive. Most importantly however, the EXO-RP condition produced significantly less long latency activity than did EGO-RP. This would suggest that when reaching to an exocentrically-placed target (static with respect to the moving platform), the long latency postural responses must be modulated to a greater extent than when the target moves with the moving body to ensure movement success.En position debout, l'activité postural programmée en mode proactif est produite dans les membres de soutien avent des mouvements d'atteindre le bras, soit pour assurer la stabilité ou à induire le mouvement du corps entier nécessaire pour atteindre vers une cible. Alternativement, lorsque la posture est perturbée de manière inattendue, par exemple par un mouvement brusque de la surface d'appui, à la fois des réponses posturales à latence courte et à latence longue s'ensuivre. Comment ces deux modes (commandes prédictives et commandes en rétroaction) interagissent au cours de tâches posturales dynamiques reste incertaine. On a investigué cette interaction par examinant si les réactions posturales automatiques (APR) évoqués au cours d'atteindre une cible sur une plate-forme mobile sont modulés différemment si la cible se déplace avec le corps (une cible égocentrique, EGO), plutôt que si la cible se déplace indépendamment du corps (cible EXO). On a varié le début des perturbations de plate-forme de se produire soit dans la phase d'accélération (RPa) ou décélération de la portée (RPd). Analyse de l'activité EMG a révélé que les APRs de latences courtes ont étés réduits dans les conditions RP fois par rapport à P, et les APRs de latences longues ont étés significativement réduits. La réduction de la phase longue de latence de l'APR était supérieure dans les conditions de RPd que RPa, suggérant que les perturbations pendent la phase d'accélération de la portée sont plus perturbateur. Plus important cependant, la condition EXO produit des activités de latence longue significativement réduit en amplitude que EGO. Cela suggère que les réponses posturales de latence longue doivent être modulée à une plus grande mesure pour les portées à une cible exocentrique (statique par rapport a la plate-forme mobile), que si la cible se déplace avec le corps pour assurer le succès du mouvement

Independent control of limb force underlies stability during voluntary head movements in standing humans

Postural stability during voluntary head movements is maintained through the integration of vestibular and neck afferent inputs. These inputs combine to accurately estimate trunk position in space, relative to a turning head. In animals, a loss of vestibular information leads to an active destabilization of balance as neck afferent information is interpreted as a movement of the trunk under a stable head (Stapley et al. 2006)

Postural configuration does not alter unperturbed or perturbed reach movement kinematics

This study investigated whether postural configuration has a significant effect upon the kinematics of arm movements when humans performed unconstrained reach movements to visual targets. Eight subjects were required to reach to static visual targets (unperturbed REACH movements) or correct reach movements when the position of a target unexpectedly changed during the execution of a planned movement (perturbed reaches, or online corrections, OC). Subjects were required to execute REACH and OC movements in sitting and standing (STAND) positions. The height of the targets, distance from the right shoulder (acromion) and eccentricity in terms of the body midline were standardized between the two postural conditions before movements begun. Unperturbed REACH movements were executed to a central target placed at 130 % of outstretched arm length, along the midline (0). Perturbed (OC) movements involved subjects initiating an arm movement to the 0° target upon its illumination. Two hundred milliseconds after the onset of the hand movement, the 0° target was extinguished and the target at 60° to the right of the midline (still at 130 % outstretched arm distance) illuminated. Subjects had to correct their reach movements online to the new target. Results demonstrated that, despite evident differences in postural kinematics between the four experimental conditions (e.g. pelvis obliquity and trunk/pelvis rotation), postural configuration had little or no effect upon the endpoint kinematics of the finger. Most importantly, the STAND position, with its greater postural constraints, did not affect the time taken to initiate an OC, nor did it lengthen the time taken to complete the REACH or OC movements. Our results suggest, therefore, that postural constraints are accounted for by the central nervous system when executing complex arm reaching movements

Comparison of a robotic-assisted gait training program with a program of functional gait training for children with cerebral palsy: design and methods of a two group randomized controlled cross-over trial

Abstract Background Enhancement of functional ambulation is a key goal of rehabilitation for children with cerebral palsy (CP) who experience gross motor impairment. Physiotherapy (PT) approaches often involve overground and treadmill-based gait training to promote motor learning, typically as free walking or with body-weight support. Robotic-assisted gait training (RAGT), using a device such as the Lokomat®Pro, may permit longer training duration, faster and more variable gait speeds, and support walking pattern guidance more than overground/treadmill training to further capitalize on motor learning principles. Single group pre-/post-test studies have demonstrated an association between RAGT and moderate to large improvements in gross motor skills, gait velocity and endurance. A single published randomized controlled trial (RCT) comparing RAGT to a PT-only intervention showed no difference in gait kinematics. However, gross motor function and walking endurance were not evaluated and conclusions were limited by a large PT group drop-out rate. Methods/design In this two-group cross-over RCT, children are randomly allocated to the RAGT or PT arm (each with twice weekly sessions for eight weeks), with cross-over to the other intervention arm following a six-week break. Both interventions are grounded in motor learning principles with incorporation of individualized mobility-based goals. Sessions are fully operationalized through manualized, menu-based protocols and post-session documentation to enhance internal and external validity. Assessments occur pre/post each intervention arm (four time points total) by an independent assessor. The co-primary outcomes are gross motor functional ability (Gross Motor Function Measure (GMFM-66) and 6-minute walk test), with secondary outcome measures assessing: (a) individualized goals; (b) gait variables and daily walking amounts; and (c) functional abilities, participation and quality of life. Investigators and statisticians are blinded to study group allocation in the analyses, and assessors are blinded to treatment group. The primary analysis will be the pre- to post-test differences (change scores) of the GMFM-66 and 6MWT between RAGT and PT groups. Discussion This study is the first RCT comparing RAGT to an active gait-related PT intervention in paediatric CP that addresses gait-related gross motor, participation and individualized outcomes, and as such, is expected to provide comprehensive information as to the potential role of RAGT in clinical practice. Trial registration ClinicalTrials.gov NCT0219629

Postural adjustments to support surface perturbations during reaching depend upon body-target reference frame

We investigated whether target position relative to the body modifies the postural adjustments produced when reaching movements are perturbed by unexpected displacements of the support surface. Eleven healthy participants reached to a target located at their midline, acromion height and at 130 % their outstretched arm length. They stood on two force plates mounted on a moveable platform, capable of delivering horizontal forward ramp-and-hold perturbations. Three types of trial were given: reach only (R), perturbations only (P) and reaching movements during which a perturbation was given at a random delay after reach onset (RP). The target could be mounted either on a frame suspended from the ceiling such that it remained world-fixed (exocentric target, RP/X) or at an equivalent position on the moving platform so that it moved with the body (egocentric target, RP/E). Arm and body 3D kinematics and muscle activity from the right tibialis anterior (rTA) and soleus (rSOL) muscles were recorded. Normalised rTA activity was significantly lower in RP than in P trials. Furthermore, long-latency rTA muscle activity was lower in RP/E than in RP/X conditions when perturbations were given during either the arm deceleration phase of reaching. The rSOL muscle activity was lowest for the RP/E (arm deceleration) condition. When balance is perturbed during reaching, the manner in which the target moves relative to the body determines the muscle activity produced in the lower-limb muscles. Furthermore, a target that moves with the body requires a different regulation of muscle activity compared with one that moves independently of the body

Comparisons of schizotypal traits across 12 countries: Results from the International Consortium for Schizotypy Research

2018 Background: Schizotypal traits are expressions of underlying vulnerability to psychotic disorders which have a potential impact on mental health status, neurocognition, quality of life, and daily functioning. To date, little research has examined epidemiologic landscape of schizotypal traits at the cross-national level. Our aim was to study the expression of schizotypal traits by sex, age, and country in a combined sample gathered from 12 countries. Methods: A total of 27,001 participants completed the Schizotypal Personality Questionnaire (SPQ). The mean age of participants was 22.12 (SD = 6.28); 37.5% (n = 10,126) were males. Results: Schizotypal traits varied according to sex, age, and country. Females scored higher than males in the positive dimension, whereas males scored higher in the disorganization dimension. By age, a significant decrease in the positive schizotypal traits was observed. Epidemiological expression of schizotypal traits varied by country. Moreover, several interactions by sex, age, and country were found. Conclusions: This pattern is similar to those found in patients with psychosis and psychotic-like experiences. These findings provide new insights and the opportunity to explore the phenotypic expression of schizotypal traits at cross-national level