Plantar stimulation alters brain connectivity in idiopathic Parkinson's disease.

OBJECTIVE: Individuals with Parkinson's disease (PD) and freezing of gait (FOG) present peripheral and central sensitivity disturbances that impair motor performance. This study aimed to investigate long-term effects of plantar sensory stimulation on brain activity, brain connectivity, and gait velocity of individuals with PD and FOG. METHODS: Twenty-five participants were enrolled in this clinical trial (NCT02594540). Plantar sensory stimulation was delivered using the Automated Mechanical Peripheral Stimulation therapy (AMPS). Volunteers were randomly assigned to real or placebo AMPS groups and received eight sessions of treatment. The primary outcome was brain activity (task-based fMRI-active ankle dorsi-plantar flexion). Secondary outcomes were brain connectivity (resting state-RS fMRI) and gait velocity. fMRI was investigated on the left, right, and mid-sensory motor regions, left and right basal ganglia. RESULTS: No changes in brain activity were observed when task-based fMRI was analyzed. After real AMPS, RS functional connectivity between basal ganglia and sensory-related brain areas increased (insular and somatosensory cortices). Gait velocity also increased after real AMPS. A positive correlation was found between gait velocity and the increased connectivity between sensory, motor and supplementary motor cortices. CONCLUSION: Plantar sensory stimulation through AMPS was not able to modify brain activity. AMPS increased the RS brain connectivity mainly in areas related to sensory processing and sensorimotor integration. Plantar stimulation could be a way to improve plantar sensitivity and consequently ameliorate gait performance. However, the mechanisms behind the way AMPS influences brain pathways are still not completely known.

Movement smoothness during a functional mobility task in subjects with Parkinson's disease and freezing of gait - an analysis using inertial measurement units.

BACKGROUND: Impairments of functional mobility may affect locomotion and quality of life in subjects with Parkinson's disease (PD). Movement smoothness measurements, such as the spectral arc length (SPARC), are novel approaches to quantify movement quality. Previous studies analyzed SPARC in simple walking conditions. However, SPARC outcomes during functional mobility tasks in subjects with PD and freezing of gait (FOG) were never investigated. This study aimed to analyze SPARC during the Timed Up and Go (TUG) test in individuals with PD and FOG. METHODS: Thirty-one participants with PD and FOG and six healthy controls were included. SPARC during TUG test was calculated for linear and angular accelerations using an inertial measurement unit system. SPARC data were correlated with clinical parameters: motor section of the Unified Parkinson's Disease Rating Scale, Hoehn & Yahr scale, Freezing of Gait Questionnaire, and TUG test. RESULTS: We reported lower SPARC values (reduced smoothness) during the entire TUG test, turn and stand to sit in subjects with PD and FOG, compared to healthy controls. Unlike healthy controls, individuals with PD and FOG displayed a broad spectral range that encompassed several dominant frequencies. SPARC metrics also correlated with all the above-mentioned clinical parameters. CONCLUSION: SPARC values provide valid and relevant clinical data about movement quality (e.g., smoothness) of subjects with PD and FOG during a functional mobility test.

Automated Mechanical Peripheral Stimulation Effects on Gait Variability in Individuals With Parkinson Disease and Freezing of Gait: A Double-Blind, Randomized Controlled Trial.

OBJECTIVE: To assess the effects of automated peripheral stimulation (AMPS) in reducing gait variability of subjects with Parkinson disease (PD) and freezing of gait (FOG) treated with AMPS and to explore the effects of this treatment on gait during a single task (walking) and a dual task (walking while attending the word-color Stroop test). DESIGN: Interventional, double-blinded, placebo-controlled, randomized trial. SETTING: Clinical rehabilitation. PARTICIPANTS: Thirty subjects were randomized into 2 groups: AMPS (n=15) and AMPS sham (n=15). INTERVENTIONS: Both groups received 2 treatment sessions a week for 4 consecutive weeks (totaling 8 treatment sessions). AMPS was applied by using a medical device (Gondola™) and consisted in mechanical pressure stimulations delivered by metallic actuators on 4 areas of the feet. Treatment parameters and device configuration were modified for AMPS sham group. MAIN OUTCOME MEASURES: Gait analyses were measured at baseline and after the first, fourth, and eighth treatment sessions. RESULTS: Interactions among groups and sessions were found for both conditions while off anti-Parkinsonian medications. AMPS decreased gait variability in subjects with PD and FOG for both single and dual task conditions. CONCLUSIONS: AMPS is an effective add-on therapy for treating gait variability in patients with PD and FOG.

Analyzing gait variability and dual-task interference in patients with Parkinson's disease and freezing by means of the word-color Stroop test.

The ability to carry out two tasks at once is critical to effective functioning in the real world and deficits are termed Dual-task interference or effect-DTE. DTE substantially compromised the gait of subjects with Parkinson's disease and freezing of gait (PD + FOG), leading to exaggerated slowing, increasing gait dysrhythmicity, and inducing FOG episodes. This study aimed to investigate the DTE in gait variability of subjects with PD and freezing of gait (PD + FOG). Thirty-three patients with PD + FOG and 14 healthy individuals (REFERENCE) took part at this study. Two gait conditions were analyzed: usual walking (single task) and walking while taking the word-color Stroop test (dual task). The computed variables were as follows: gait velocity, step length, step timing, gait asymmetry, variability measures and DTE of each variable. The PD + FOG group has presented negative DTE values for all analyzed variables, indicating dual task cost. The REFERENCE group has presented dual-task benefits for step length standard deviation and step time. Differences between both groups and conditions were found for all variables, except for step time. Taking the word-color Stroop test while walking led to a larger dual-task cost in subjects with PD + FOG.

Alteration in the center of mass trajectory of patients after stroke.

BACKGROUND: The movement disorders due to stroke can alter the motion of the Center of Mass (CoM) of the body. Thus, the analysis of the CoM motion can be an alternative to diagnostic the stroke gait disturbances and has not been widely explored. OBJECTIVE: To identify and to analyze the alterations of CoM trajectory during both of gait cycles, affected and unaffected, of post-stroke patients comparing to healthy subjects. METHODS: The CoM trajectory was obtained using a gold standard method, the three-dimensional (3D) kinematics associate to anthropometry. Two experimental groups were compared: Hemiparetic Group (HG) consisted of fourteen chronic hemiparetic patients and Control Group (CG) by fourteen able-bodied subjects. RESULTS: The statistical analysis (P ≤ 0.05) revealed the following average gait alterations in the HG, in the stance phase of the affected side: higher lateral (midstance), lower vertical (midstance and terminal stance), and lower forward displacement (heel strike until terminal stance). In the swing phase of the affected side, HG showed higher lateral (preswing and initial swing) and vertical displacement (preswing until terminal swing), and lower forward (preswing until terminal swing) displacement of the CoM. There was also anticipation of the instants of maximum displacements in the lateral and vertical directions and lower total range in the forward direction. CONCLUSION: The CoM trajectory analysis pointed out that the gait after stroke was altered such in the affected as in the unaffected lower limbs, mainly in the single support phase of the affected side, but also in the swing phase of the gait cycle.

Active Videogame Training Combined with Conventional Therapy Alters Body Oscillation in Children with Cerebral Palsy: A Randomized Controlled Trial.

Objective: Assess the effect of nonimmersive virtual reality (VR) training as complementary rehabilitation on body oscillation in children with cerebral palsy (CP) while standing on different bases of support and surfaces. Materials and Methods: Twenty-three children with unilateral CP randomly allocated to an intervention group (IG, n = 12) or control group (CG, n = 11). The IG underwent two weekly 50-minute sessions of VR training over 8 weeks, associated with conventional therapy, while the CG was submitted to two 45-minute sessions of conventional neurodevelopmental-based physiotherapy a week over the same time period. Participants were evaluated on a force platform under control conditions (CCs) (rigid surface, feet parallel); semitandem stance; flexible surface (FS) with feet parallel; and flexible surface in a semitandem (FSST) stance. The effect of the group and time factors on the center of pressure oscillation variables was analyzed by repeated-measures analysis of variance (ANOVA), with significance set at 0.05. Results: The main effect observed was for time on the FS, with a decline in the amplitude of mediolateral (ML Amp) (P = 0.01) and mediolateral root mean square (P = 0.01) after intervention. In the IG, ML Amp also declined after intervention under CCs (P = 0.02) and total velocity increased for FSST (P = 0.04). The percentage change was significant only in the IG. Conclusion: VR training as complementary rehabilitation can help improve body oscillation in children with CP and mild functional impairment. Nonimmersive VR can be considered a complementary tool for the physical rehabilitation of children with CP. This study was registered with the Brazilian Clinical Trials Registry (RBR-3zty4w).

Nonimmersive Virtual Reality as Complementary Rehabilitation on Functional Mobility and Gait in Cerebral Palsy: A Randomized Controlled Clinical Trial.

Objective: This study aimed to investigate the effects of nonimmersive virtual reality (VR) as complementary rehabilitation on functional mobility and gait in children with mild unilateral cerebral palsy (CP). Methods: Prospective, randomized, controlled, clinical trial. Twenty-two children with unilateral CP were randomized into two groups: intervention group (IG) (n = 11) and control group (n = 11). After baseline assessments, the participants either started the VR intervention (IG) associated with conventional therapy, or continued conventional physical therapy (control group). Participants in the IG attended 45-minute training sessions twice a week for 8 weeks (total: 16 sessions and 12 hours of training). Participants in the control group underwent standard therapy for 50 minutes, twice a week. Timed Up and Go test (TUG), gait spatiotemporal variables, and pelvic angles were measured at baseline and after treatment sessions. Results: When compared with the control group, the IG performed the following activities in decreased time: TUG, and stride time. Also, the IG increased the velocity of walking and the pelvis retroversion, and decreased the pelvis interval/external rotations and amplitude of pelvis rotation while walking. Conclusions: A rehabilitative approach based on a nonimmersive VR as complementary rehabilitation may improve functional mobility and change joint mobility functions during gait of children with mild unilateral CP. The results of the study demonstrate that the insertion of a therapy based on VR may help in better strategies in the gait of children with CP. Thus, rehabilitation professionals can use this tool combined with conventional therapy.

Assessing Interlimb Jump Asymmetry in Young Soccer Players: The My Jump 2 App.

BACKGROUND: Jumps are important evaluation tools for muscle strength and power and for interlimb asymmetries. Different jump tests are well related to athletic performance, prediction of injury risk, and common motor gestures of several sports such as soccer. Low-cost mobile applications (apps) have gained popularity for this measure. The authors hypothesized that the My Jump 2 app would be a valid tool to assess drop-jump performance and interlimb asymmetry in soccer players. METHODS: Eleven male soccer players took part in this study (18.2 [1.3] y, 69.9 [9.5] kg, 174 [6.6] cm). The athletes performed each test twice on a force plate (gold-standard method), while the jumps were recorded through the mobile app. Measures with the My Jump 2 app were applied by 2 evaluators, independently and in duplicate (interrater and intrarater reliability). The agreement analysis between both evaluations was done using an intraclass correlation coefficient and Bland-Altman plots. RESULTS: Compared with the force platform, the app tested showed excellent reliability for the drop jump's flight time and interlimb asymmetry (intraclass correlation coefficient > .98). For interlimb contact-time asymmetry, the values were 18.4 (9.9) and 19.1 (9.9) milliseconds for the My Jump 2 app and the force platform, respectively (P = .88). For flight-time asymmetries, the values were 389.7 (114.3) and 396.8 (112.5) milliseconds for the My Jump 2 app and the force platform, respectively (P = .88). CONCLUSION: The My Jump 2 app is a valid tool to assess drop-jump and interlimb asymmetry in soccer players.

Changes in plantar load distribution in legally blind subjects.

We investigated the impact of visual impairment on balance control. We measured the center of pressure (COP) between the two feet and plantar surface pressures on each foot in 18 normal-sighted participants and compared their data with measures from 18 legally blind participants, either acquired or congenital. Pressures were measured in open- and closed-eye conditions using a baropodometric resistive plate. In the eyes-open condition, there were no differences between the sighted and legally blind groups in COP displacement. However, participants with visual loss had significantly increased pressures in two metatarsal regions (M1 and M2 zones) of the plantar surface in both viewing conditions (p < 0.05). The differences in pressure measures between the normally sighted and legally blind groups could be attributed mainly to the subgroup of subjects with acquired impairment. Our findings suggest that subjects with visual impairment present increased metatarsal pressures (i.e. forefoot), not yet associated to anterior displacement of COP or impaired balance control.

Postural adjustments impairments in elderly people with chronic low back pain.

Chronic low back pain (CLBP) is associated with postural control impairments and is highly prevalent in elderly people. The objective of this study is to verify whether anticipatory postural adjustments (APAs) and compensatory postural adjustments (CPAs) are affected by CLBP in elderly people by assessing their postural control during a self-initiated perturbation paradigm induced by rapid upper arm movement when pointing to a target. The participants' lower limb muscle onset and center of pressure (COP) displacements were assessed prior to perturbation and throughout the entire movement. T0 moment (i.e., the beginning of the movement) was defined as the anterior deltoid (DEL) onset, and all parameters were calculated with respect to it. The rectus femoris (RT), semitendinosus (ST), and soleous (SOL) showed delayed onset in the CLBP group compared with the control group: RF (control: - 0.094 ± 0.017 s; CLBP: - 0.026 ± 0.012 s, t = 12, p < 0.0001); ST (control: - 0.093 ± 0.013 s; CLBP: - 0.018 ± 0.019 s, t = 12, p < 0.0001); and SOL (control: - 0.086 ± 0.018 s; CLBP: - 0.029 ± 0.015 s, t = 8.98, p < 0.0001). In addition, COP displacement was delayed in the CLBP group (control: - 0.035 ± 0.021 s; CLBP: - 0.015 ± 0.009 s, t = 3; p = 0.003) and presented a smaller amplitude during APA COPAPA [control: 0.444 cm (0.187; 0.648); CLBP: 0.228 cm (0.096; 0.310), U = 53, p = 0.012]. The CLBP group required a longer time to reach the maximum displacement after the perturbation (control: 0.211 ± 0.047 s; CLBP 0.296 ± 0.078 s, t = 3.582, p = 0.0013). This indicates that CLBP elderly patients have impairments to recover their postural control and less efficient anticipatory adjustments during the compensatory phase. Our results suggest that people with CLBP have altered feedforward hip and ankle muscle control, as shown from the SOL, ST, and RT muscle onset. This study is the first study in the field of aging that investigates the postural adjustments of an elderly population with CLBP. Clinical assessment of this population should consider postural stability as part of a rehabilitation program.

Hand Resting Tremor Assessment of Healthy and Patients With Parkinson's Disease: An Exploratory Machine Learning Study.

The aim of this study is comparing the accuracies of machine learning algorithms to classify data concerning healthy subjects and patients with Parkinson's Disease (PD), toward different time window lengths and a number of features. Thirty-two healthy subjects and eighteen patients with PD took part on this study. The study obtained inertial recordings by using an accelerometer and a gyroscope assessing both hands of the subjects during hand resting state. We extracted time and temporal frequency domain features to feed seven machine learning algorithms: k-nearest-neighbors (kNN); logistic regression; support vector classifier (SVC); linear discriminant analysis; random forest; decision tree; and gaussian Naïve Bayes. The accuracy of the classifiers was compared using different numbers of extracted features (i.e., 272, 190, 136, 82, and 27) from different time window lengths (i.e., 1, 5, 10, and 15 s). The inertial recordings were characterized by oscillatory waveforms that, especially in patients with PD, peaked in a frequency range between 3 and 8 Hz. Outcomes showed that the most important features were the mean frequency, linear prediction coefficients, power ratio, power density skew, and kurtosis. We observed that accuracies calculated in the testing phase were higher than in the training phase. Comparing the testing accuracies, we found significant interactions among time window length and the type of classifier (p < 0.05). The study found significant effects on estimated accuracies, according to their type of algorithm, time window length, and their interaction. kNN presented the highest accuracy, while SVC showed the worst results. kNN feeding by features extracted from 1 and 5 s were the combination with more frequently highest accuracies. Classification using few features led to similar decision of the algorithms. Moreover, performance increased significantly according to the number of features used, reaching a plateau around 136. Finally, the results of this study suggested that kNN was the best algorithm to classify hand resting tremor in patients with PD.

Obstacle stepping and body scale modulating parameters.

The purpose of this study was to investigate gait spatial parameters at the point of departure, with obstacle heights adjusted to individual body scale. Undergraduate student volunteers (M age = 22.4 yr., SD = 2.1; 6 women, 1 man) were asked to step once, then cross over an obstacle and stop. This behavior was video recorded to extract kinematic data. The obstacle heights corresponded to high (knee-height) and low obstacles (half the knee-height). Points of departure corresponded to far (length of the lower limb) and close (half the length of the lower limb). The close point of departure influenced the trailing foot's placement ahead of the obstacle as well as step length. The high obstacle influenced the trailing foot's toe clearance. An interaction between factors was observed for leading foot toe clearance. Results indicate that body scale affected the participants' locomotor behavior during the obstacle-avoidance task.

Wearable sensors, cerebral palsy and gait assessment in everyday environments: is it a reality? - A systematic review.

This systematic review aimed to investigate emerging methods used to quantify gait parameters in children with cerebral palsy (CP) in everyday environments. The StArt computational tool automatically screened the following databases: ACM, Engineering Village, IEEE, PubMed, Scopus and Web of Science from inception to June 2018. Studies reporting the use of wearable sensors to assess gait in daily settings in children with CP were included. Data regarding 1563 studies were extracted, but only three studies could be included on the basis of the inclusion/ exclusion criteria. These studies proposed wearable technologies based on the use of signals provided by triaxial accelerometers and force resistive pressure sensors. These are able to track levels of activity and detect falls, gait deviations and gait symmetry in children with CP in their daily environments. To date, only two types of sensors have been tested in this population and it remains to be clarified how wearable sensors, used to quantify activity level, might benefit children with CP.

Slip avoidance strategies in children with bilateral spastic cerebral palsy and crouch gait.

BACKGROUND: A slip occurs when the required friction (RCOF) to prevent slipping at the foot/floor interfaces exceeds the available friction. The RCOF is dependent upon the biomechanics features of individuals and their gait. On the other hand, the available friction depends on environmental features. Once individuals with crouch gait have their biomechanics of gait completely altered, how do they interact with a supporting surface? The aim was to quantify the RCOF in children with bilateral spastic cerebral palsy (BSCP) and crouch gait. METHODS: 11 children with crouch gait and 11 healthy age-matched children were instructed to walk barefoot at self-selected speed over a force platform. The RCOF curve was obtained as the ratio between the tangential forces (FT), and the vertical ground reaction force (FZ). Three points were extracted by the RCOF, FT and FZ curves at the loading response, midstance and push-off phases. FINDINGS: Children with BSCP presented higher values of RCOF in all support phase and lower gait velocity relative to the healthy controls. For BSCP group no correlation between FT and FZ were found, indicating that this group is not able to negotiate the forces during the support phase. INTERPRETATION: Children with BSCP and crouch gait are not able to negotiate the forces applied on the ground in support phase, so to avoid the fall, their strategy is to reduce the gait velocity.

Peripheral neurostimulation breaks the shuffling steps patterns in Parkinsonian gait: a double blind randomized longitudinal study with automated mechanical peripheral stimulation.

BACKGROUND: The shuffling steps pattern is a typical feature of gait in patients affected by Parkinson's disease (PD), which progressively reduces their quality of life, being related to the risk of falls in this population. Recently, Automated Mechanical Peripheral Stimulation (AMPS) was presented as an integrative rehabilitative treatment based on peripheral stimulation able to improve the gait spatiotemporal parameters in PD patients. AIM: The aim of this study was to evaluate the effects of AMPS on shuffling steps pattern by analyzing the kinematic and spatio-temporal gait parameters. DESIGN: Double blind randomized longitudinal study. SETTING: Outpatients. POPULATION: PD patients. METHODS: In this double blind randomized longitudinal study, 14 patients with PD were treated with effective-AMPS (AMPS group), while 14 PD patients were treated with placebo-AMPS (SHAM group); 32 healthy subjects were deemed the control group (CG). A dedicated medical device (Gondola™ Medical Technologies, Stabio, Switzerland) was used to deliver both stimulations. Each treatment session lasted about 15 minutes, including preparation (approx. 10 to 13 minutes) and stimulation (approx. 2 minutes). All PD patients were given six AMPS/SHAM treatments sessions, twice a week, delivered during the off-levodopa phase, having withdrawn from dopaminergic medication overnight. We evaluated spatio-temporal and kinematic variables of gait with quantitative 3D-gait analysis as follows: before and after the first intervention (acute phase), then after the sixth session (long term phase). RESULTS: We detected differences in all gait variables immediately after the first session of AMPS treatment and again after the sixth stimulation session. CONCLUSIONS: AMPS treatment changes the shuffling steps pattern that is typical of PD subjects, increasing the ROM of hip, knee and ankle joints during the gait cycle. CLINICAL REHABILITATION IMPACT: This data presents further evidence that a rehabilitative approach based on the AMPS treatment can induce improvements in the gait pattern of patients affected by PD.

Plantar stimulation in parkinsonians: From biomarkers to mobility - randomized-controlled trial.

BACKGROUND: The decrease of Brain-Derived Neurotrophic Factor (BDNF) serum levels has been related to the pathophysiology of several neurodegenerative diseases as well as to neural plasticity and rehabilitation. Automated Mechanical Peripheral Stimulation (AMPS) has been investigated as a complementary therapy for Parkinson Disease (PD). OBJECTIVES: (1) to investigate the effects of AMPS on BDNF and Cortisol serum levels of subjects with PD; (2) to evidence the interplay between BDNF and Cortisol serum levels and the functional mobility improvement after AMPS treatment. METHODS: Thirty-three subjects with PD were randomized into two groups: effective stimulation (AMPS, n = 16) or placebo stimulation (AMPS SHAM, n = 17). Fourteen healthy aged-matched subjects were included as a reference group. Each AMPS group received eight sessions of treatment using a commercial medical device (Gondola™). BDNF and Cortisol serum levels, spatiotemporal gait parameters and TUG test were assessed at baseline and after eight sessions of treatment. RESULTS: After the treatment, AMPS group showed significantly higher levels of BDNF and lower levels of Cortisol compared to AMPS SHAM. AMPS group also showed a positive effect on gait pattern as a higher improvement on gait velocity, stride length, and TUG performance was shown. CONCLUSION: Effective AMPS treatment increased BDNF and decreased Cortisol serum levels and produced improvements in functional mobility.

Effect of virtual reality training on walking distance and physical fitness in individuals with Parkinson's disease.

OBJECTIVE: To evaluate the effects of gait training with virtual reality (VR) on walking distance and physical fitness in individuals with Parkinson's Disease (PD). METHODS: Thirty-seven individuals with PD participated in this prospective, randomized, controlled clinical trial. They were randomly allocated to a control group submitted to conventional training (n = 12), a treadmill group submitted to gait training on a treadmill (n = 13) and a VR group submitted to gait training using the XboxTM (n = 12). Clinical measures, gait variables and the Six-Minute Walk Test (6MWT) were evaluated: pre-intervention, after one intervention session, post-intervention and follow up (30 days after intervention). RESULTS: The VR and treadmill groups travelled longer distances on the 6MWT and had faster gait speed in comparison to the control group. The VR and treadmill groups demonstrated an increase in pre-6MWT HR. The VR group had more intense HR after the first session and throughout training, but these gains were not maintained at the follow-up. CONCLUSION: The present findings demonstrate that gait training with a VR program is as effective as treadmill training with regard to gains in walking distance and improvements in temporal gait variables in individuals with PD.

Automated Mechanical Peripheral Stimulation Improves Gait Parameters in Subjects With Parkinson Disease and Freezing of Gait: A Randomized Clinical Trial.

OBJECTIVE: This study aimed to assess spatiotemporal gait parameters and range of motion of lower limbs in subjects with Parkinson disease (PD) and freezing of gait, treated with automated mechanical peripheral stimulation (AMPS) or AMPS SHAM (placebo). DESIGN: This randomized clinical trial included 30 subjects allocated into two groups: AMPS (15 subjects with PD) and AMPS SHAM (15 subjects with PD). Fourteen age-matched healthy subjects were also included as a reference group. Both PD groups received the treatment twice a week during 4 weeks. Automated mechanical peripheral stimulation was applied using a commercial medical device (Gondola) and consisted of mechanical pressure in four areas of feet. For AMPS SHAM group, a subliminal stimulus was delivered. Gait analysis were measured before, after the first, after the fourth, and after the eighth sessions. RESULTS: We did not find significant differences between AMPS and AMPS SHAM groups either for spatiotemporal gait parameters or for range of motion of lower limbs. However, within-group analysis showed that AMPS group significantly improved spatiotemporal gait parameters and hip rotation range of motion throughout the treatment period. The AMPS SHAM group did not show any improvement. CONCLUSIONS: Automated mechanical peripheral stimulation therapy induces improvements in spatiotemporal parameters and hip rotation range of motion of subjects with PD and freezing of gait. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES: Upon completion of this article, the reader should be able to: (1) Understand the impact of reduced plantar sensitivity on gait in individuals with Parkinson disease; (2) Identify the improvements on spatiotemporal gait parameters in subjects with Parkinson disease and freezing of gait after automated mechanical peripheral stimulation therapy; and (3) Recommend the use of new strategies of plantar stimulus for gait disorders of subjects with Parkinson disease. LEVEL: Advanced ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 0.5 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Timed Up and Go evaluation with wearable devices: Validation in Parkinson's disease.

The Timed Up and Go test (TUG) is used to assess individual mobility. It evaluates static and dynamic balance by means of the total time required to complete the test, usually measured by a stopwatch. In recent years tools based on portable inertial measurement units (IMU) for clinical application are increasingly available on the market. More specifically, a tool (hardware and dedicated software) to quantify the TUG test based on IMU is now available. However, it has not yet been validated in subjects with Parkinson's disease (PD). Thus, the aim of this study is to compare measurements from instrumented TUG tests (or iTUG) acquired by an IMU with those obtained using an optoelectronic system (the gold standard) and by a stopwatch, to gain an in-depth understanding of IMU behavior in computing iTUG in subjects with PD. To do this, three TUG test trials were carried out on 30 subjects with PD and measured with all three systems simultaneously. System agreements were evaluated using Intraclass Correlation Coefficient and Bland-Altman plots. The device tested showed excellent reliability, accuracy and precision in quantifying total TUG test duration. Since TUG is a widely used test in rehabilitation settings, its automatic quantification through IMUs could potentially improve the quality of assessments in the quantification of PD gait ability.

The required coefficient of friction in Parkinson's disease: people with freezing of gait.

The required coefficient of friction (RCOF) is frequently reported in the literature as an indicator of slip propensity, a consequence of the collisional aspect of legged locomotion. Little is known about the RCOF in pathological gait. Therefore, this study aimed to quantify the RCOF in subjects with Parkinson's disease (PD) and freezing of gait (FOG) during the OFF-pharma phase, and to investigate the interplay between RCOF parameters and ankle kinematic and kinetic gait variables. Fourteen subjects with PD and 14 healthy age-matched subjects were instructed to walk barefoot at self-selected speed over a force platform. The RCOF curve was obtained as the ratio between the tangential and vertical ground reaction forces. Then, the following discrete variables were identified: P1COF (the peak at the loading response phase), V1COF (the valley at midstance phase) and P2COF (the peak at push-off phase). Stepwise multiple regressions were applied to observe the influence of the gait speed and ankle kinematic and kinetic gait variables on RCOF variables. In subjects with PD and FOG the gait speed is a predictor of the RCOF in the loading response phase; plantarflexion and the plantarflexion moment are strong predictors of the RCOF in midstance; finally, push-off power is a predictor of RCOF increasing in the push-off phase. These results characterized the biomechanical strategies adopted by subjects with PD and FOG during gait in order to avoid falls.