1,721,083 research outputs found
Neuromechanical measurement of motor impairments in relation to upper limb activity limitations after stroke
No full textLoss of upper-limb function is a problem following stroke. Recent research has led to the emergence of new treatments but progress is hampered by lack of reliable objective measures of impairment, and understanding of the underlying impairment mechanisms associated with loss and recovery of functional activity. The aim of this research was to identify, using neuromechanical measurement methods, inter-relationships between motor impairments, and correlates of motor impairments with functional activity limitation in the upper limb of acute and chronic stroke survivors.An instrumented rig has been developed to measure impairments: muscle weakness, active range of movement, motor control accuracy in rhythmic and discrete tracking tasks, spasticity, coactivation, contracture and non-neural stiffness. In pilot studies, signal processing and data analysis techniques have been used to generate novel, clinically and physiologically relevant indices to quantify impairments. In a Main Study, 13 older impaired participants in the acute phase post-stroke, 13 in the chronic phase 14 age-matched unimpaired participants underwent rig assessments and performed a test of upper limb activity. A sub-group of impaired participants were tested on two days for test-retest reliability evaluation.Statistical tests have confirmed the validity of the impairments to distinguish between acute and chronic patients and unimpaired individuals, except coactivation during discrete movements and non-neural stiffness. Repeatability coefficients for the active test indices have been presented as benchmark values for use in future trials. The muscle activation indices showed lower repeatability which highlights the challenge of using these to measure change over time. The impairments that contributed to lower motor control accuracy were reduced extensor weakness, delayed extensor onset timing, coactivation and smaller extension AROM and PROM; coactivation was more strongly associated with motor control accuracy than with spasticity or stiffness.The most important contributors to functional activity in the acute group was extensor weakness, and in the chronic group was motor control accuracy and coactivation (rhythmic task). Contracture was important contributor in both groups, and was associated with weakness and loss of active range of movement rather than spasticity. The findings support the notion that rehabilitation strategies should focus on increasing muscle strength and prevention of contracture. However, assessment of more complex impairments like motor control accuracy and coactivation may be crucial to better target therapy, especially in the later phases post-stroke
Wrist motor control and coactivation during step-tracking in post-stroke hemiplegia and unimpaired adults
No full textThe influence of left hand movement using neuromuscular electrical stimulation on unilateral visuo-spatial neglect following right-sided stroke
No full textA pilot study to investigate the association between muscle activation patterns, wrist tracking performance and upper limb function in post-stroke hemiplegia
No full textExploring wrist motor control in stroke patients, using a target tracking task
No full textMotor impairments following an upper motor lesion such as stroke include weakness, loss of motor control, and fatigability, as well as characteristics associated with increased levels of involuntary activity: spasticity, increased tendon reflexes, clonus associated reactions, spasms, and coactivation during movement. Subsequent to the initial insult, limb movement may be impaired by mechanical changes, including shortening and increased stiffness of muscles and soft tissue around joints leading to contracture. These combined impairments may affect the individuals ability to move effectively and perofrm the functional tasks. Imporved understanding of patients' specific impairment may aid in optimizing individualized theraputic interventions, and in assessing progress in rehabilitation. The current work presents an experimental rig that aims to measure patients ability to track a target by moving their wrist, and some of the first results on assessing tracking performance and co-activation of flexor and extensor muscles
Validity and reliability of a tool to measure impairment changes in preparation for the RF Bion® micro-stimulator upper limb project
No full textCoactivation during wrist movement: relationship with motor control and upper limb functional activity in post-stroke hemiplegia
No full textThe association between muscle activation patterns, wrist tracking performance and upper limb function in post-stroke hemiplegia
No full text
- …
