Posts Tagged Reaching
[Abstract] A Portable Passive Rehabilitation Robot for Upper-Extremity Functional Resistance Training
[Abstract] Sensing motion and muscle activity for feedback control of functional electrical stimulation: Ten years of experience in Berlin
[Abstract] Role of contralesional hemisphere in paretic arm reaching in patients with severe arm paresis due to stroke: A preliminary report
- The functional relevance of contralesional hemisphere in paretic arm motor performance in individuals with severe arm paresis was examined.
- TMS pulses were delivered to the contralesional primary motor and dorsal pre-motor areas.
- Various temporal and spatial characteristics were measured in conditions with and without TMS.
- Movement time was significantly slower with TMS to contralesional hemisphere.
- The study suggests functionally relevant role of contralesional hemisphere motor areas during paretic arm reaching movements in stroke survivors.
Stroke is highly prevalent and a leading cause of serious, long-term disability among American adults. Impaired movement (i.e. paresis) of the stroke-affected arm is a major contributor to post-stroke disability, yet the mechanisms of upper extremity motor recovery are poorly understood, particularly in severely impaired patients who lack hand function.
To address this problem, we examined the functional relevance of the contralesional hemisphere in paretic arm motor performance in individuals with severe arm paresis.
Twelve individuals with severe stroke-induced arm paresis (Upper Extremity Fugl-Meyer Assessment = 17.1 ± 8.5; maximum score = 66) participated in the study.
Participants performed a reaching response time task with their paretic arm. At varying time intervals following a ‘Go’ cue, a pair of transcranial magnetic stimulation (TMS) pulses were delivered to contralesional hemisphere primary motor (M1) or dorsal pre-motor cortex (PMd) to momentarily disrupt the pattern of neural firing. Response time components and hand-path characteristics were compared across the 2 sites for trials with and without TMS disruption. There was no significant effect of TMS disruption on overall Response time or Reaction time, but Movement time was significantly longer (i.e. slower) with disruption of the contralesional hemisphere (p = 0.015), regardless of which area was stimulated. Peak hand-path velocity and hand-path smoothness were also significantly lower (p = 0.005 and p < 0.0001, respectively) with TMS disruption of the contralesional hemisphere.
The data from this study provide evidence supporting a functionally relevant role of contralesional hemisphere motor areas in paretic arm reaching movements in individuals with severe post-stroke arm impairment.
[Abstract] A clinically feasible kinematic assessment method of upper extremity motor function impairment after stroke
The development of feasible kinematic assessment methods of upper extremity motor function impairment after stroke is clinically extremely important in physiotherapy and rehabilitation engineering. Microsoft Kinect has a potential of a low-cost and compact solution for clinical based assessment of the upper limb motor function after stroke. However, the reliability of Microsoft Kinect in the upper limb motor function assessment has not been well established. Therefore, there is a hesitation in usage of Microsoft Kinect for clinical applications. It is expected that any measurement procedure has the capability to differentiate between pathological and normal performance. On the other hand, the identification of the kinematic metrics that best evaluate impairment of upper-extremity motor function is a key problem of any measurement protocol. Primary objective of our study is, by differentiating pathological performance from the healthy performance and identifying the kinematic metrics that best evaluate the impairment, to demonstrate the robustness/usability of Microsoft Kinect in kinematic analysis of motor performance of stroke patients. We compared the kinematic metrics of the forward reaching movement obtained data recorded from Microsoft Kinect between three stroke patients and two healthy subjects based on the Principal Component Analysis (PCA). In the study, we have defined a new inter-joint coordination index (IJCI) based on PCA to capture inter-joint coordination dynamic of reaching movement in addition to other metrics those have been previously defined and used in literature to quantify upper limb impairment. We observed that the IJCI has significant importance to detect impairment of upper-extremity motor function during a forward reaching task and to discriminate stroke patients from healthy controls.
We hope that this paper will promote the acceptance of objective kinematic analysis into routine rehabilitation practices.
[ARTICLE] Kinematic analysis of upper limb motion: Feasibility, preliminary results in controls and hemiparetic subjects, prospects
The aim of this study is to develop a valid and standardized instrumental analysis of upper limb (UL) motion in stroke patients.
Sixteen controls and 15 hemiparetic subjects (mean age = 54 ± 18,2 years old; Fugl-Meyer Upper Limb 41,4 ± 12,4) underwent kinematic motion analysis (passive markers, Optitrack) of pointing and grasping tasks. We examined the ability to perform a single pointing task and three reach-to-grasp tasks: key turning, reaching and grasping a can, reaching and grasping a cube; at a self-selected speed and as fast as possible. Speed, accuracy and efficiency of each movement were quantified and compared between controls and hemiparetic subjects, and between the ipsilateral of control subjects and the affected side; to describe reaching and grasping.
For reaching, movement time of hemiparetic UL was longer, less smooth (peak velocity, jerk), less direct (higher index path ratio) and associated with more trunk compensation (higher trunk/hand ratio). Movement time, jerks and trunk/hand ratio were the most discriminant variables between hemiparetic UL and ipsilateral/control UL, in any task analysed. Trunk displacement was greater in grasping than in reaching tasks. For grapsing tasks, movement time is the most discriminant factor between hemiparetic and control/ipsilateral UL, especially for the key turn task. Movement alterations were also found for ipsilateral limb. Association between kinematic variables and clinical features during reaching time (Fugl-Meyer, MAL, WFMT, ARAT) was greater for the task “grasping a can”.
Our results are similar to those of the literature, but suggest that we have to privilege some of the most relevant kinematic parameters. This standardization phase emerging after a validation phase of the techniques can make the biomechanical analysis of the upper limb as easy and valid as gait analysis and should help to develop the quantified measurement of prehension. This protocol is currently in process to objectively assess the therapeutic effects of rehabilitation treatments (botulinum toxin, induced constraint therapy).
ARTICLE: Timing of motor cortical stimulation during planar robotic training differentially impacts neuroplasticity in older adults – Full Text
– Altering the timing of stimulation during a reaching intervention changes the direction and extent of plasticity
– Non-invasive brain stimulation may be a catalyst to promote plasticity in older adults.
– Robotic reaching plus stimulation facilitated a rapid plastic response that was maintained during the intervention and for a short time period following the intervention.