Mechanisms of motor recovery in chronic and subacute stroke patients following a robot-aided training.

The aim of this article is to propose a methodology for analyzing different recovery mechanisms in subacute and chronic patients through evaluation of biomechanical parameters. Twenty-five post-stroke subjects, eight subacute and seventeen chronic, participated in the study. A 2-DoF robotic system was used for upper limb training. Two clinical scales were used for assessment. Forces and velocities at the robot's end-effector during the execution of upper limb planar reaching movements were measured. Clinical outcome measures show a significant decrease in motor impairment after the treatment both in chronic and subacute patients (MSS-SE, p<0.001; FM, p<0.05). Movement velocity increases after the robot-aided treatment in both groups. Mean values of forces exerted by subacute patients are lower than those observed in chronic patients, both at the beginning and at the end of robotic treatment, as in the latter the pathological pattern is already structured. Our results demonstrate that the monitoring of the forces exerted on the end-effector during robot-aided treatment can identify the specific motor recovery mechanisms at different stages. If the pathological pattern is not yet structured, rehabilitative interventions should be addressed toward the use of motor re-learning procedures; on the other hand, if the force analysis shows a strong pathological pattern, mechanisms of compensation should be encouraged.

Robot-aided therapy on the upper limb of subacute and chronic stroke patients: a biomechanical approach.

The goal of this study is to propose a methodology for evaluating recovery mechanisms in subacute and chronic post-stroke patients after a robot-aided upper-limb therapy, using a set of biomechanical parameters. Fifty-six post-stroke subjects, thirteen subacute and forty-three chronic patients participated in the study. A 2 dof robotic system, implementing an "assist-as-needed" control strategy, was used. Biomechanical parameters related (i) to the speed measured at the robot's end-effector and (ii) to the movement's smoothness were computed. Outcome clinical measures show a decrease in motor impairment after the treatment both in chronic and subacute patients. All the biomechanical parameters show an improvement between admission and discharge. Our results show that the robot-aided training can contribute to reduce the motor impairment in both subacute and chronic patients and identify neurophysiological mechanisms underlying the different stages of motor recovery.

Epidemiological study on knowledge, attitudes and behaviour of health care workers with respect to HIV infection.

To analyse knowledge, perception of risk, attitudes and behaviour towards HIV infection among health workers in two hospitals in the North-East of Italy, we sent all health care workers who were working in direct contact with patients an anonymous self-administered questionnaire covering personal and occupational data, perception and knowledge of risk, behaviour in routine activities, attitudes towards and care of HIV patients. The response rate was 70.06%. The perception of the risk of acquiring HIV infection was influenced by occupational qualification, by work unit and by having cared for a HIV-positive patient. Scientific knowledge about transmissibility of HIV infection was poor and 11.3% of the staff did not know the Universal Precautions. 28.3% behaved correctly in recapping needles, but with patients considered not at risk 29.9% did not use any protection in drawing venous blood. A significant portion of staff showed low willingness to care for HIV-positive patients. We found a high mean perception of the risk of contracting HIV infection through occupational exposure; health workers overestimated the specific risk and wrong behavioural attitudes persisted. To conclude, more attention should be paid to educational programs for health workers.