Comparing auditory, visual and vibrotactile cues in individuals with Parkinson's disease for reducing risk of falling over different types of soil.

INTRODUCTION: Several researchers have demonstrated the positive benefits of auditory and visual cueing in the gait improvements among individuals with Parkinson's disease (PD). However, few studies have evaluated the role of vibrotactile cueing when compared to auditory and visual cueing. This paper compares how these stimuli affect the risk of falling while walking on six types of soil (concrete, sand, parquet, broken stone, two types of carpet). METHODS: An instrumented Timed Up and Go (iTUG) test served to evaluate how audio, visual and vibrotactile cueing can affect the risk of falling of elderly. This pilot study proposes 12 participants with PD (67.7 ± 10.07 years) and nine age-matched controls (66.8 ± 8.0 years). Both groups performed the iTUG test with and without cueing. The cueing frequency was set at 10% above the cadence computed at the lower risk level of falling (walking over the concrete). A computed risk of falling (ROFA) index has been compared to the TUG time (total TUG duration). RESULTS: The index for evaluating the risk of falling appears to have a good reliability (ICC > 0.88) in this pilot study. In addition, the minimal detectable change (MDC) suggests that the proposed index could be more sensitive to the risk of falling variation compared to the TUG time. Moreover, while using the cueing, observed results suggest a significant decrease in the computed risk of falling compared to 'without cueing' for most of types of soil, especially for deformable soils, which can lead to falls. CONCLUSION: When compared to other cueing, it seems that audio could be a better neurofeedback for reducing the risk of falling over different walking surfaces, which represent important risk factors for persons with gait disorder or lost functional autonomy.

Use of an Enactive Insole for Reducing the Risk of Falling on Different Types of Soil Using Vibrotactile Cueing for the Elderly.

BACKGROUND: Our daily activities imply displacements on various types of soil. For persons with gait disorder or losing functional autonomy, walking on some types of soil could be challenging because of the risk of falling it represents. METHODS: In this paper, we present, in a first part, the use of an enactive shoe for an automatic differentiation of several types of soil. In a second part, using a second improved prototype (an enactive insole), twelve participants with Parkinson's disease (PD) and nine age-matched controls have performed the Timed Up and Go (TUG) test on six types of soil with and without cueing. The frequency of the cueing was set at 10% above the cadence computed at the lower risk of falling (walking over the concrete). Depending on the cadence computed at the lower risk, the enactive insole activates a vibrotactile cueing aiming to improve gait and balance control. Finally, a risk index is computed using gait parameters in relation to given type of soil. RESULTS: The frequency analysis of the heel strike vibration allows the differentiation of various types of soil. The risk computed is associated to an appropriate rhythmic cueing in order to improve balance and gait impairment. The results show that a vibrotactile cueing could help to reduce the risk of falling. CONCLUSIONS: Firstly, this paper demonstrates the feasibility of reducing the risk of falling while walking on different types of soil using vibrotactile cueing. We found a significant difference and a significant decrease in the computed risks of falling for most of types of soil especially for deformable soils which can lead to fall. Secondly, heel strike provides an approximation of the impulse response of the soil that can be analyzed with time and frequency-domain modeling. From these analyses, an index is computed enabling differentiation the types of soil.

Corticomotor excitability in Parkinson's disease during observation, imagery and imitation of action: effects of rehabilitation using wii fit and comparison to healthy controls.

BACKGROUND: Parkinson's disease (PD) is responsible for a progressive motor impairment. Wii Fit game represents an innovative treatment modality using external visual cueing, which can be used to help patients with PD in executing motor tasks and improving function. OBJECTIVES: The objectives of this study were (1) to compare lower limb corticomotor activation in subjects with and without PD during action observation (OBS), motor imagery (IMAG), and imitation (IMIT), and (2) to evaluate the effects of a 6-week training program using Wii Fit on corticomotor excitability during these 3 conditions. METHODS: Using transcranial magnetic stimulation, we assessed motor evoked potentials (MEPs) in Quadriceps Femoris (QF) and Soleus (SOL) muscles in 8 subjects with moderate PD (PD group) and 8 healthy subjects (HS group) before and after 6 weeks of training using Wii Fit during OBS, IMAG and IMIT of a mini-squat action. RESULTS: At baseline, PD showed significantly less MEPs in QF during OBS, IMAG and IMIT compared with HS. In SOL, MEPs were reduced in PD only during IMIT. Following training, PD increased QF MEPs during OBS, which was opposite to the decrease in QF MEPs noted in HS. During IMAG, increased MEPs were found only in PD for SOL. During IMIT, both groups significantly reduced MEPs in both QF and SOL. CONCLUSION: Subjects with PD may have improved their dual-task ability considering changes observed during OBS and IMIT. Visual cueing training using Wii Fit may provide an interesting rehabilitation method for PD.

Effect of repetitive afferent electrical stimulation of the lower limb on corticomotor excitability and implications for rehabilitation.

Despite the extensive work published on the effects of electrical stimulation on corticomotor excitability, very few studies have focused on lower limb muscles. The aim of the present study was to determine the effect of high-frequency afferent electrical stimulation of the anterior thigh area on the corticomotor excitability of lower limb muscles. Twenty-two healthy subjects (mean age 23 ± 7 years) participated in the study. Electrical stimulation was applied for 60 minutes on the anterior thigh area (frequency 100 Hz, pulse duration 60 µs, intensity below motor threshold). Motor-evoked potentials (MEP) of the rectus femoris (RF) and biceps femoris (BF) muscles were recorded before, and after, the electrical stimulation paradigm with a Magstim 200 stimulator. Analyses revealed a significant modulation in MEP amplitude for the RF but not for the BF muscle. Specifically, there was a significant reduction in MEP amplitude for the RF muscle immediately, 15 minutes and 30 minutes after the end of electrical stimulation when compared with baseline. Our results indicate that a 60-minute high-frequency electrical stimulation protocol applied on the anterior thigh area decreases the corticomotor excitability of the RF muscle. Although the exact duration remains unknown, the pattern of modulation observed indicates that the inhibitory effect lasts for more than 30 minutes after the end of stimulation, giving enough time for clinicians to work on the desired motor task during rehabilitation.

Home-based balance training programme using Wii Fit with balance board for Parkinsons's disease: a pilot study.

OBJECTIVES: To evaluate the effects of a home-based balance training programme using visual feedback (Nintendo Wii Fit game with balance board) on balance and functional abilities in subjects with Parkinson's disease, and to compare the effects with a group of paired healthy subjects. SUBJECTS: Ten subjects with moderate Parkinson's disease and 8 healthy elderly subjects. METHODS: Subjects participated in a 6-week home-based balance training programme using Nintendo Wii Fit and balance board. Baseline measures were taken before training for the Sit-to-Stand test (STST), Timed-Up-and-Go (TUG), Tinetti Performance Oriented Mobility Assessment (POMA), 10-m walk test, Community Balance and Mobility assessment (CBM), Activities-specific Balance and Confidence scale (ABC), unipodal stance duration, and a force platform. All measurements were taken again after 3 and 6 weeks of training. RESULTS: The Parkinson's disease group significantly improved their results in TUG, STST, unipodal stance, 10-m walk test, CBM, POMA and force platform at the end of the 6-week training programme. The healthy subjects group significantly improved in TUG, STST, unipodal stance and CBM. CONCLUSION: This pilot study suggests that a home-based balance programme using Wii Fit with balance board could improve static and dynamic balance, mobility and functional abilities of people affected by Parkinson's disease.

Cortico-motor excitability of the lower limb motor representation: a comparative study in Parkinson's disease and healthy controls.

OBJECTIVE: To compare indices of cortico-motor excitability derived from transcranial magnetic stimulation (TMS) of the lower limb motor representation in patients with Parkinson's diseases (PD) and healthy controls. METHODS: The cortico-motor excitability of the lower limb motor area was studied both at rest (motor threshold, amplitude of motor evoked potentials (MEPs)) and during active contraction of the quadriceps (Quad) muscle (MEPs facilitation and silent period) in 10 PD patients (11 legs) and 11 healthy controls using single pulse TMS. RESULTS: At rest, the motor threshold was found to be significantly lower and the amplitude of MEPs larger in patients than in controls. During active knee contraction, patients produced lower levels of MEP facilitation with respect to baseline values and the silent period was lengthened in comparison to controls. CONCLUSIONS: The present results provide further evidence from the lower limb motor area that enhanced cortico-spinal excitability is an important feature in the pathophysiology of PD.