Gait strategy and body composition in patients with Prader-Willi syndrome.

PURPOSE: Individuals with Prader-Willi syndrome (PWS) exhibit reduced lean body mass and increased fat-lean mass ratio when compared with individuals of normal weight and obese ones. Thus, research on the association of functional limitations during gait and body composition may be of great importance from a rehabilitative viewpoint. In particular, the aim of this study was to compare the gait profile of persons with PWS to that of unaffected individuals and to see if a relationship exists between gait profile and body composition in individuals with PWS. METHODS: Eighteen individuals with PWS and 20 unaffected individuals (Healthy Group: HG) were assessed. Their gait pattern was quantified with 3D-Gait Analysis (3D-GA). Overall body weight, lean and fat masses were measured by dual-energy X-ray absorptiometry. RESULTS: Individuals with PWS were found to be characterized by a significantly different (p < 0.05) gait pattern with respect to healthy controls in terms of both kinematic and kinetic parameters. No correlations were found between kinematic parameters and overall mass and lean/fat mass, while some parameters associated with ground reaction force were found to be significantly correlated with overall mass, lean mass and fat mass. Significant regression models were obtained, including impact and propulsive force and loading rate. CONCLUSION: Our data suggest that in individuals with PWS, gait is influenced by the overall and lean body mass. Thus, therapeutic strategies should target both weight reduction and lean mass increase to optimize gait, minimize articular stress, and reduce the risk of repetitive strain on the lower limbs. LEVEL OF EVIDENCE: Level III: Case-control analytic study.

Changes in symmetry during gait in adults with Prader-Willi syndrome.

Most studies on locomotion of individuals with the Prader-Willi Syndrome (PWS) have been performed in a laboratory setting using quantitative motion analysis. Recently, wireless inertial sensors have been successfully employed for gait analysis in different pathological states with the advantages of reproducing a testing condition very close to those encountered in daily living. Using such devices, it is possible not only to characterize the conventional spatio-temporal parameters, but also extract information on further less conventional metrics, such as the harmonic ratio (HR), a measure of step-to-step symmetry based on trunk acceleration processing. In the present study, this technique was used to quantify gait parameters during level walking in 20 adults with PWS who were compared to 20 unaffected individuals. While no differences between the two groups were found in terms of spatio-temporal parameters, individuals with PWS exhibited significantly reduced values of HR in the antero-posterior and vertical directions. Such results, which indicate a poorer gait symmetry in PWS, suggest that upper body accelerations, as well as HR, provide novel information on gait in people with PWS that could not be extracted from spatio-temporal parameters only.

An Integrated Multi-Sensor Approach for the Remote Monitoring of Parkinson's Disease.

The increment of the prevalence of neurological diseases due to the trend in population aging demands for new strategies in disease management. In Parkinson's disease (PD), these strategies should aim at improving diagnosis accuracy and frequency of the clinical follow-up by means of decentralized cost-effective solutions. In this context, a system suitable for the remote monitoring of PD subjects is presented. It consists of the integration of two approaches investigated in our previous works, each one appropriate for the movement analysis of specific parts of the body: low-cost optical devices for the upper limbs and wearable sensors for the lower ones. The system performs the automated assessments of six motor tasks of the unified Parkinson's disease rating scale, and it is equipped with a gesture-based human machine interface designed to facilitate the user interaction and the system management. The usability of the system has been evaluated by means of standard questionnaires, and the accuracy of the automated assessment has been verified experimentally. The results demonstrate that the proposed solution represents a substantial improvement in PD assessment respect to the former two approaches treated separately, and a new example of an accurate, feasible and cost-effective mean for the decentralized management of PD.

Proprioceptive Focal Stimulation (Equistasi®) May Improve the Quality of Gait in Middle-Moderate Parkinson's Disease Patients. Double-Blind, Double-Dummy, Randomized, Crossover, Italian Multicentric Study.

Objective: The object of the study was to evaluate the efficacy of Proprioceptive Focal Stimulation on Gait in middle-advanced Parkinson (PD) patients by a crossover, randomized, double Blind double dummy study using Equistasi®, a nano-technological device of the dimension of a plaster which generates High Frequency Vibration (FV). Background: The efficacy of Gait Analysis (GA) on evaluating gait modification on Parkinson's disease (PD) Patients is already well-known. Therefore, GA was recorded in a group of PD patients using Equistasi® device and its placebo. Methods: Forty PD patients on optimal therapy were enrolled in the study. Patients were randomly assigned to receive active or sham stimulation for 8 weeks and, following a wash-out period, switched to an additional 8-week period with the reverse intervention. GA was performed at baseline and at the end of both 8-weeks treatment periods Clinical state was monitored by MDUPDRS part III. Results: Active stimulation induced a significant improvement in Mean Velocity (Velocity), Stride Length (SL), Stance (STA), and Double Support (DST) percentage, both in left and right stride. The ANOVA analysis using H&Y stage as a factor, showed that DST and MDUPDRS III scores improved significantly more in the more severely affected subjects. Conclusions: The findings obtained in this randomized controlled study show the efficacy of mechanical focal vibration, as stimulation of the proprioceptive system, in PD and encourage further investigation. The effect of the device on more severe patients may open a new possibility to identify the most appropriate candidate for the management of gait disturbances and postural instability with FV delivered with Equistasi®.

Symmetry of Gait in Underweight, Normal and Overweight Children and Adolescents.

Abnormal excess or lack of body mass can influence gait patterns, but in some cases such differences are subtle and not easy to detect, even with quantitative techniques for movement analysis. In these situations, the study of trunk accelerations may represent an effective way to detecting gait anomalies in terms of symmetry through the calculation of Harmonic Ratio (HR), a parameter obtained by processing trunk accelerations in the frequency domain. In the present study we used this technique to assess the existence of differences in HR during gait in a cohort of 75 healthy children and early adolescents (aged 7-14 years) stratified into 3 equally-sized age and gender-matched groups (Underweight: UW; Normal Weight: NW; Overweight: OW). The accelerometric signal, acquired using a single wearable inertial sensor, was processed to calculate stride length, speed, cadence and HR in antero-posterior, vertical and medio-lateral directions. No differences in spatio-temporal parameters were found among groups, while the HR in the medio-lateral direction was found significantly lower in UW children, while OW exhibited the highest values. On the basis of the results obtained, HR appears capable of discriminating gait symmetry in children with different body mass even when conventional gait parameters are unchanged.

Feasibility of Home-Based Automated Assessment of Postural Instability and Lower Limb Impairments in Parkinson's Disease.

A self-managed, home-based system for the automated assessment of a selected set of Parkinson's disease motor symptoms is presented. The system makes use of an optical RGB-Depth device both to implement its gesture-based human computer interface and for the characterization and the evaluation of posture and motor tasks, which are specified according to the Unified Parkinson's Disease Rating Scale (UPDRS). Posture, lower limb movements and postural instability are characterized by kinematic parameters of the patient movement. During an experimental campaign, the performances of patients affected by Parkinson's disease were simultaneously scored by neurologists and analyzed by the system. The sets of parameters which best correlated with the UPDRS scores of subjects' performances were then used to train supervised classifiers for the automated assessment of new instances of the tasks. Results on the system usability and the assessment accuracy, as compared to clinical evaluations, indicate that the system is feasible for an objective and automated assessment of Parkinson's disease at home, and it could be the basis for the development of neuromonitoring and neurorehabilitation applications in a telemedicine framework.

Do wearable sensors add meaningful information to the Timed Up and Go test? A study on obese women.

The purpose of this study was to validate Time Up and Go test (TUG) as measured by a single Inertial Measurement Unit (IMU) placed on the lower back to that measured by a stopwatch in obese and normal weight women; in addition, the comparison of the performance of TUG test between obese and healthy women using the instrumented TUG (iTUG). Forty-four severely obese women and 14 age-matched healthy women were assessed simultaneously by IMU and stopwatch. The comparison between manual and instrumented assessment of total time duration showed no significant differences both in the healthy (8.32 ±â€¯0.96 s vs. 8.52 ±â€¯0.97 s, p > 0.05) and in the obese group (9.99 ±â€¯2.28 s vs. 9.81 ±â€¯2.52 s; p > 0.05). The comparison between obese and healthy group exhibited significant differences in terms of total time duration both during manual and iTUG, which is longer in obese women than normal weight women. The duration of the sub-phases in obese group is longer with the exception of sit-to-stand and stand-to-sit phase, with lower turning velocity both in mid- and final turning sub-phase. The results suggest that the iTUG is an objective and fast mobility test and it could add useful information to the manual TUG for clinical practice.

Slow versus traditional strength training in obese female participants: preliminary results.

The aim of this study was to provide comparative data on a slow versus a traditional supervised resistance training in an obese female population. Forty obese female patients admitted to our rehabilitation hospital were assigned randomly to a slow training group (ST group; mean age: 47.44 years, mean BMI: 38.53 kg/m) and a traditional training group (TT group; mean age: 54.34 years, mean BMI: 39.37 kg/m). The ST protocol included five repetitions for five consecutive bouts on the leg press and extension machine. The duration of each repetition (concentric+eccentric phases) was 6 s for leg press and 5 s for leg extension. The initial load was 50% of the one repetition maximum and then gradually reduced by 20% for each bout. The TT protocol included six consecutive repetitions for five bouts on the leg press and leg extension with 80% of the one repetition maximum load. Both groups performed 10 sessions. All of the patients were assessed by a visual analogue scale for pain, a Borg scale for subjective fatigue, and an isokinetic strength test. Statistically significant strength improvements were observed in both groups. In ST group statistically significant improvements in visual analogue scale scores for knee pain were found at post, larger than that observed in TT group. Subjectively perceived fatigue on the Borg scale decreased more at post in ST group in comparison with TT group. Our preliminary data suggest that ST may represent a preferential strengthening method in obese patients as it can lead to significant strength gains with a relatively lower loading effect on the knee, and hence reduced perception of pain.

A Self-Managed System for Automated Assessment of UPDRS Upper Limb Tasks in Parkinson's Disease.

A home-based, reliable, objective and automated assessment of motor performance of patients affected by Parkinson's Disease (PD) is important in disease management, both to monitor therapy efficacy and to reduce costs and discomforts. In this context, we have developed a self-managed system for the automated assessment of the PD upper limb motor tasks as specified by the Unified Parkinson's Disease Rating Scale (UPDRS). The system is built around a Human Computer Interface (HCI) based on an optical RGB-Depth device and a replicable software. The HCI accuracy and reliability of the hand tracking compares favorably against consumer hand tracking devices as verified by an optoelectronic system as reference. The interface allows gestural interactions with visual feedback, providing a system management suitable for motor impaired users. The system software characterizes hand movements by kinematic parameters of their trajectories. The correlation between selected parameters and clinical UPDRS scores of patient performance is used to assess new task instances by a machine learning approach based on supervised classifiers. The classifiers have been trained by an experimental campaign on cohorts of PD patients. Experimental results show that automated assessments of the system replicate clinical ones, demonstrating its effectiveness in home monitoring of PD.

Defective Tool Embodiment in Body Representation of Individuals Affected by Parkinson's Disease: A Preliminary Study.

When efficiently used for action, tools become part of the body, with effect on the spatial-temporal movement parameters and body size perception. Until now, no previous investigation has been reported about tool embodiment in Parkinson's disease (PD), which is a neurological disease characterized by several sensory and motor symptoms affecting body and action. We enrolled 14 individuals affected by PD and 18 healthy individuals as controls. We studied the spatial-temporal parameters on self-paced free pointing movement task, via an optoelectronic system, before and after a short training in which a 27-cm long rod was used to point toward a far target. Moreover, we investigated changes in estimation of arm length through the Tactile Estimation Task. After the tool-use training, controls showed changes in spatial-temporal parameters: they were slower to perform movements and reported a higher value of deceleration than the baseline. However, such a difference did not emerge in the PD individuals. In the Tactile Discrimination Task, no difference emerged before and after the tool-use training in both groups. Our results were suggestive of possible difficulties of the tool embodiment process in PD. We discussed our results in relation to aberrant multisensory integration as well as in terms of the effect of PD sensory and motor symptoms on body schema plasticity. The present study points at a novel way to conceive PD sensory motor signs and symptoms in terms of their effect on individuals' body representation.

Effects of nanotechnology-based devices on postural control in healthy subjects.

BACKGROUND: The aim of the present preliminary randomized controlled study was to ascertain whether the use of newly developed nanotechnologies-based patches can influence posture control of healthy subjects. METHODS: Thirty healthy female subjects (age 39.4 years, BMI 22.74 kg/m2) were randomly assigned to two groups: one with active patches and a control group with sham patches. Two patches were applied with a tape: one on the subject's sternum and the other on the C7 apophysis. Body sway during quiet upright stance was recorded with a dynamometric platform. Each subject was tested under two visual conditions, eyes open and closed. We used a blocked stratified randomization procedure conducted by a third party. RESULTS: Subjects wearing the sham patches showed a significant increase of the center of pressure sway area after 4 hours when they performed the habitual moderate-intensity work activities. In the active patch group, a decrease of the sway path was evident, providing evidence of an enhanced balance control. CONCLUSIONS: Our preliminary findings on healthy subjects indicate that nanotechnological devices generating ultra-low electromagnetic fields can improve posture control.

Quantitative comparison between the laser scanner three-dimensional method and the circumferential method for evaluation of arm volume in patients with lymphedema.

OBJECTIVE: Several methods are used to evaluate arm volumes. The most commonly used methods are water displacement and the circumferential method (CM), but these techniques have some limitation in application in clinical settings and accuracy. Recently, the laser scanner three-dimensional (LS3D) method was successfully proposed as a valid method for volume measurements of the upper limb in healthy individuals. The aim of the study was to compare, in terms of intraobserver and interobserver reliability, the CM and LS3D method to measure the upper limb in a group of women with upper limb lymphedema. METHODS: There were 200 women with upper limb lymphedema (mean age, 64 ± 9 years; body mass index, 24.72 ± 2.94 kg/m2) involved in this study. Arm measurements were obtained with both the CM and LS3D method. Statistical analysis was conducted to compare the CM and LS3D method. RESULTS: Both the CM and LS3D method have a satisfactory level of agreement, but we found some statistically significant differences in terms of some measurements (both circumferential and volume measurements). CONCLUSIONS: The data obtained in this study indicate that the LS3D method could represent a reliable, valid method to measure arm circumferences and volumes in arms with lymphedema, suitable for daily clinical use. It combines precision, reproducibility, and ease of use with the possibility of measuring geometric parameters and shape information of scanned limbs.

Range of motion limitations of the upper body in obese female workers.

BACKGROUND: The prevalence of obesity is increasing worldwide, and the economic consequences of an increased percentage of obese workers are relevant in terms of health costs and absences from work. Obesity is associated with reduced participation in the workforce, increased absence from work, disability and health costs, lower salaries and reduced productivity. OBJECTIVES: We aimed at quantifying the limitations in range of motion (ROM) of the upper limb and the trunk of obese workers during basic occupational tasks. METHODS: One group of 15 obese female subjects (BMI: 42.10±9.10 kg/m2) and one control group of 13 normal-weight female subjects were recruited. Three group of tasks were selected as representative of basic occupational movements: 1) upper limb movements (reaching, abduction-adduction, frontal elevation); 2) trunk movements (lateral bending, rotation); 3) whole body movement (target task). RESULTS: We observed significant range of motion limitations in lateral and frontal upper arm elevation. Statistically significant difference in terms of center of pressure (the point of application of the ground reaction force measured by means of force platform) excursions was observed for lateral bending and trunk rotation tasks. CONCLUSIONS: Our results show that obese subjects have significant range of motion limitations of the upper body during basic occupational activities. This study provides quantitative evidence of these limitations of obese workers and may serve occupational specialists to allocate them to adequate jobs and reduce the rate of work-related musculoskeletal disorders.

Body-scaled action in obesity during locomotion: Insights on the nature and extent of body representation disturbances.

OBJECTIVE: Conscious perception of our own body, also known as body image, can influence body-scaled actions. Certain conditions such as obesity are frequently accompanied by a negative body image, leaving open the question if body-scaled actions are distorted in these individuals. METHODS: To shed light on this issue, we asked individuals affected by obesity to process dimensions of their own body in a real action: they walked in a straight-ahead direction, while avoiding collision with obstacles represented by door-like openings that varied in width. RESULTS: Participants affected by obesity showed a body rotation behavior similar to that of the healthy weighted, but differences emerged in parameters such as step length and velocity. CONCLUSION: When participants with obesity walk through door-like openings, their body parts rotation is scaled according to their physical body dimensions; however, they might try to minimize risk of collision. Our study is in line with the hypothesis that unconscious body-scaled actions are related to emotional, cognitive and perceptual components of a negative body image.

Gait initiation and termination strategies in patients with Prader-Willi syndrome.

BACKGROUND: Gait Initiation (GI) is a functional task representing one of the first voluntary destabilizing behaviours observed in the development of a locomotor pattern as the whole body centre of mass transitions from a large to a small base of support. Conversely, Gait Termination (GT) consists in the transition from walking to standing which, in everyday life, is a very common movement. Compared to normal walking, it requires higher control of postural stability. For a safe GT, the forward movement of the body has to be slowed down to achieve a stable upright position. Stability requirements have to be fulfilled for safe GT. In individuals with Prader-Willi syndrome (PWS), excessive body weight negatively affects the movement, such as walking and posture, but there are no experimental studies about GI and GT in these individuals. The aim of this study was to quantitatively characterise the strategy of patients with PWS during GI and GT using parameters obtained by the Center of Pressure (CoP) track. METHODS: Twelve patients with PWS, 20 obese (OG) and 19 healthy individuals (HG) were tested using a force platform during the GI and GT tasks. CoP plots were divided into different phases, and duration, length and velocity of the CoP trace in these phases were calculated and compared for each task. RESULTS: As for GI, the results showed a significant reduction of the task duration and lower velocity and CoP length parameters in PWS, compared to OG and HG. In PWS, those parameters were reduced to a higher degree with respect to the OG. During GT, longer durations, similar to OG, were observed in PWS than HG. Velocity is reduced when compared to OG and HG, especially in medio-lateral direction and in the terminal part of GT. CONCLUSIONS: From these data, GI appears to be a demanding task in most of its sub-phases for PWS individuals, while GT seems to require caution only towards the end of the task. Breaking the cycle of gait into the phases of GI and GT and implementing specific exercises focusing on weight transfer and foot clearance during the transition phase from the steady condition to gait will possibly improve the effectiveness of rehabilitation and fall and injury prevention.

Dizziness and Falls in Obese Inpatients Undergoing Metabolic Rehabilitation.

AIM: The relationship between dizziness and falls in the obese population is a relatively unexplored issue. The aims of the present study were to define the 1-year prevalence of dizziness in an obese inpatient population undergoing metabolic rehabilitation and to investigate possible correlations with fall events. MATERIALS AND METHODS: We recruited 329 obese subjects: 203 female (BMI 43,74 kg/m2 ± 0.5 SE; age 17-83 years, 58.33 ± 0.9 SE) and 126 male (BMI 44,27kg/m2 ± 0.7 DE age 27-79 years, 58.84 ± 1 SE). To assess dizziness we used the validated Italian version (38) of the Dizziness Handicap Inventory (DHI). RESULTS: Out of the experimental sample, 100 subjects did not complain of dizziness and felt confident about their balance control, while 69.6% reported some degree of dizziness. Their mean DHI score was 22.3, which corresponds to mild dizziness. Twenty-one percent reported more severe dizziness (DHI score > 40). The majority of our sample reported minor dizziness and its perception appears to be independent from BMI: DHI scores were consistent across classes of obesity. DISCUSSION: The rate of dizziness and falls (30.1%) in an this obese population was higher than that previously reported in a general matched population. However, obese subjects, in our sample, seem to underestimate their risk of fall and DHI score does not appear a reliable predictor of falls. Since complications associated with falls in obese persons generally require longer treatments than in lean individuals, our findings should be taken into account in order to identify other predictors, including cognitive and perceptual, of risk of fall and to implement fall prevention programs.

Computation of spatio-temporal parameters in level walking using a single inertial system in lean and obese adolescents.

In recent years, the availability of low-cost equipment capable of recording kinematic data during walking has facilitated the outdoor assessment of gait parameters, thus overcoming the limitations of three-dimensional instrumented gait analysis (3D-GA). The aim of this study is twofold: firstly, to investigate whether a single sensor on the lower trunk could provide valid spatio-temporal parameters in level walking in normal-weight and obese adolescents compared to instrumented gait analysis (GA); secondly, to investigate whether the inertial sensor is capable of capturing the spatio-temporal features of obese adolescent gait. These were assessed in 10 obese and 8 non-obese adolescents using both a single inertial sensor on the lower trunk and an optoelectronic system. The parameters obtained were not statistically different in either normal-weight or obese participants between the two methods. Obese adolescents walked with longer stance and double support phase compared to normal-weight participants. The results showed that the inertial system is a valid means of evaluating spatio-temporal parameters in obese individuals.

Spinal load in nurses during emergency lifting of obese patients: preliminary results.

BACKGROUND: Nurses are exposed to the risk of injury while handling patients. This is particularly true for obese patients. OBJECTIVE: The goal of this paper is to estimate the spinal loads and the related risk of injury to nurses while lifting obese patients from the floor with a bariatric sheet during a hospital emergency. METHODS: Six male nurses participated in this study. The biomechanical analysis focused on the lifting strategy. Thirty obese in-patients were enrolled to take part in the experimental study and divided into three groups according to their Body Mass Index (BMI). Three-dimensional motion analysis was conducted using an optoelectronic system. The trunk kinematics and the loading on the spines of the operating nurses were computed. RESULTS: Our data showed that when the nurse was operating from the central handle, his trunk was more flexed at the end of the lift with a reduced range of motion. The values were higher when the nurse lifted patients with higher BMIs. All kinetic parameters and tension in the lumbar muscles at the end of the movement were characterised by lower values for the nurse placed beside the patient's head or feet if compared to the operator positioned beside the central handle in all patient groups. CONCLUSIONS: Our preliminary data suggest that only the reaction load on the spine of the nurse holding the central handle, closest to the patient's centre of mass, seems to exceed the recommended safety limits.

Does kinematics add meaningful information to clinical assessment in post-stroke upper limb rehabilitation? A case report.

[Purpose] The aims of this case study were to: (a) quantify the impairment and activity restriction of the upper limb in a hemiparetic patient; (b) quantitatively evaluate rehabilitation program effectiveness; and (c) discuss whether more clinically meaningful information can be gained with the use of kinematic analysis in addition to clinical assessment. The rehabilitation program consisted of the combined use of different traditional physiotherapy techniques, occupational therapy sessions, and the so-called task-oriented approach. [Subject and Methods] Subject was a one hemiplegic patient. The patient was assessed at the beginning and after 1 month of daily rehabilitation using the Medical Research Council scale, Nine Hole Peg Test, Motor Evaluation Scale for Upper Extremity in Stroke Patients, and Hand Grip Dynamometer test as well as a kinematic analysis using an optoelectronic system. [Results] After treatment, significant improvements were evident in terms of total movement duration, movement completion velocity, and some smoothness parameters. [Conclusion] Our case report showed that the integration of clinical assessment with kinematic evaluation appears to be useful for quantitatively assessing performance changes.