Quantitative study of PIMT technique aiming its validation as physical therapy procedure.

BACKGROUND: Valgus hindfoot is a very common postural deviation, and the associated foot pronation can be a triggering factor for diseases such as tarsal tunnel syndrome. RESEARCH QUESTION: This work compares two techniques for hindfoot valgus correction: GPR (Global Postural Reeducation) and PIMT (Postural Integration by Manual Therapy). METHODS: Sixty young adult subjects from the Brazilian Army with unilateral hindfoot valgus were selected and divided into two groups of 30 subjects, one treated with GPR and the other treated with PIMT. Differences between normal and valgus hindfeet (plantar surface and body weight load) for each subject were measured and analysed, using a baropodometer with subjects in static standing position for 5s. Measurements were performed before and after each treatment session (4 weeks, once a week), and 4 weeks after the end of treatment. RESULTS: Data shows that both treatments were equally effective for improving symmetry in body weight load between feet and plantar surface. After 4 weeks from the end of treatment, both treatments were equally effective for body weight load symmetry, but plantar surface symmetry was better in PIMT treated subjects. SIGNIFICANCE: This study shows that PIMT technique can be validated as a physical therapy procedure, at least for valgus hindfoot.

Nerve stimulator for regional anaesthesia procedures with automatic interactive closed-loop control.

Peripheral nerve stimulators have widespread among anaesthesiologists and remain a popular technique. However, in commercial devices, the user has to manually adjust stimulus intensity. Thus, the aim of this study is to propose a method that allows automating the current intensity control. An earlier nerve stimulator prototype was modified to add an accelerometer and an sEMG module. The choice of these two sensors is aimed at the possibility of observing the mechanical and electrical responses of the muscle contraction evoked by the stimulation. The tests were performed in two steps. The first step was to observe how the sensors behave during stimulation and muscle contraction. The second step was to implement a control algorithm and to validate the automation technique. Comparing the two methods, no significant differences were found on procedure time (manual: 12.5 ± 2.3; automatic: 11.6 ± 1.9; ρ =0.380) and blockade latency time (manual: 11.6 ± 1.1; automatic: 11.9 ± 1.2; ρ =0.524). Comparing needle-nerve distance in manual or automatic mode, no significant differences were found for 1.0 mA, 0.8 mA, 0.5 mA and 0.3 mA. We conclude that the technique for automating the current intensity update, using accelerometer and/or electromyography, is satisfactory. Furthermore, we conclude that the use of the accelerometer alone is sufficient for detection of muscle contraction.

High-reliability microcontroller nerve stimulator for assistance in regional anaesthesia procedures.

In the last decades, the use of nerve stimulators to aid in regional anaesthesia has been shown to benefit the patient since it allows a better location of the nerve plexus, leading to correct positioning of the needle through which the anaesthetic is applied. However, most of the nerve stimulators available in the market for this purpose do not have the minimum recommended features for a good stimulator, and this can lead to risks to the patient. Thus, this study aims to develop an equipment, using embedded electronics, which meets all the characteristics, for a successful blockade. The system is made of modules for generation and overall control of the current pulse and the patient and user interfaces. The results show that the designed system fits into required specifications for a good and reliable nerve stimulator. Linearity proved satisfactory, ensuring accuracy in electrical current amplitude for a wide range of body impedances. Field tests have proven very successful. The anaesthesiologist that used the system reported that, in all cases, plexus blocking was achieved with higher quality, faster anaesthetic diffusion and without needed of an additional dose when compared with same procedure without the use of the device.

Quality of Grasping and the Role of Haptics in a 3-D Immersive Virtual Reality Environment in Individuals With Stroke.

Reaching and grasping parameters with and without haptic feedback were characterized in people with chronic post-stroke behaviors. Twelve (67 ± 10 years) individuals with chronic stroke and arm/hand paresis (Fugl-Meyer Assessment-Arm: ≥ 46/66 pts) participated. Three dimensional (3-D) temporal and spatial kinematics of reaching and grasping movements to three objects (can: cylindrical grasp; screwdriver: power grasp; pen: precision grasp) in a physical environment (PE) with and without additional haptic feedback and a 3-D virtual environment (VE) with haptic feedback were recorded. Participants reached, grasped and transported physical and virtual objects using similar movement strategies in all conditions. Reaches made in VE were less smooth and slower compared to the PE. Arm and trunk kinematics were similar in both environments and glove conditions. For grasping, stroke subjects preserved aperture scaling to object size but used wider hand apertures with longer delays between times to maximal reaching velocity and maximal grasping aperture. Wearing the glove decreased reaching velocity. Our results in a small group of subjects suggest that providing haptic information in the VE did not affect the validity of reaching and grasping movement. Small disparities in movement parameters between environments may be due to differences in perception of object distance in VE. Reach-to-grasp kinematics to smaller objects may be improved by better 3-D rendering. Comparable kinematics between environments and conditions is encouraging for the incorporation of high quality VEs in rehabilitation programs aimed at improving upper limb recovery.

Comparison of grasping movements made by healthy subjects in a 3-dimensional immersive virtual versus physical environment.

Virtual reality (VR) technology is being used with increasing frequency as a training medium for motor rehabilitation. However, before addressing training effectiveness in virtual environments (VEs), it is necessary to identify if movements made in such environments are kinematically similar to those made in physical environments (PEs) and the effect of provision of haptic feedback on these movement patterns. These questions are important since reach-to-grasp movements may be inaccurate when visual or haptic feedback is altered or absent. Our goal was to compare kinematics of reaching and grasping movements to three objects performed in an immersive three-dimensional (3D) VE with haptic feedback (cyberglove/grasp system) viewed through a head-mounted display to those made in an equivalent physical environment (PE). We also compared movements in PE made with and without wearing the cyberglove/grasp haptic feedback system. Ten healthy subjects (8 women, 62.1±8.8years) reached and grasped objects requiring 3 different grasp types (can, diameter 65.6mm, cylindrical grasp; screwdriver, diameter 31.6mm, power grasp; pen, diameter 7.5mm, precision grasp) in PE and visually similar virtual objects in VE. Temporal and spatial arm and trunk kinematics were analyzed. Movements were slower and grip apertures were wider when wearing the glove in both the PE and the VE compared to movements made in the PE without the glove. When wearing the glove, subjects used similar reaching trajectories in both environments, preserved the coordination between reaching and grasping and scaled grip aperture to object size for the larger object (cylindrical grasp). However, in VE compared to PE, movements were slower and had longer deceleration times, elbow extension was greater when reaching to the smallest object and apertures were wider for the power and precision grip tasks. Overall, the differences in spatial and temporal kinematics of movements between environments were greater than those due only to wearing the cyberglove/grasp system. Differences in movement kinematics due to the viewing environment were likely due to a lack of prior experience with the virtual environment, an uncertainty of object location and the restricted field-of-view when wearing the head-mounted display. The results can be used to inform the design and disposition of objects within 3D VEs for the study of the control of prehension and for upper limb rehabilitation.