Federica Vannetti

A light-weight active orthosis for hip movement assistance

In the last decades, wearable powered orthoses have been developed with the aim of augmenting or assisting motor activities. In particular, among many applications, wearable powered orthoses have been also introduced in the state of the art with the goal of providing lower-limb movement assistance in locomotion-related tasks (e.g.: walking, ascending/descending stairs) in scenarios of activities of daily living. In this paper we present a light-weight active orthosis endowed with two series elastic actuators for hip flexion-extension assistance. Along with the description of its mechatronic modules, we report the experimental characterization of the performance of the actuation and control system, as well as the usability test carried out with a healthy subject. Results showed a suitable dynamic behavior of the actuation unit: the closed-loop torque control bandwidth is about 15 Hz and the output impedance ranges from about 1 N m/rad to 35 N m/rad in the frequency spectrum between 0.2 and 3.2 Hz. Results from the tests with the healthy subject proved the overall system usability: the subject could walk with the device without being hindered and while he received a smooth assistive flexion-extension torque profile on both hip articulations. Development of a novel light-weight wearable powered bilateral pelvis orthosis.Design of a novel compact, light-weight series-elastic actuator (SEA).SEA closed-loop torque control bandwidth equal to 15 Hz.SEA output impedance ranges from 1 to 35 N m /rad in human gait frequency spectrum.The overall system usability was proved by tests with a healthy subject.

The effects on biomechanics of walking and balance recovery in a novel pelvis exoskeleton during zero-torque control

Fall-related accidents are among the most serious concerns in elderly people, amputees and subjects with neurological disorders. The aim of this paper was to investigate the behaviour of healthy subjects wearing a novel light-weight pelvis exoskeleton controlled in zero-torque mode while carrying out unperturbed locomotion and managing unexpected perturbations. Results showed that the proposed exoskeleton was unobtrusive and had a minimum loading effect on the human biomechanics during unperturbed locomotion. Conversely, it affected the movement of the trailing leg while subjects managed unexpected slipping-like perturbations. These findings support further investigations on the potential use of powered exoskeletons to assist locomotion and, possibly prevent incipient falls.

Effects in Short and Long Term of Global Postural Reeducation (GPR) on Chronic Low Back Pain: A Controlled Study with One-Year Follow-Up

Objective. Comparing global postural reeducation (GPR) to a standard physiotherapy treatment (PT) based on active exercises, stretching, and massaging for improving pain and function in chronic low back pain (CLBP) patients. Design. Prospective controlled study. Setting. Outpatient rehabilitation facility. Participants. Adult patients with diagnosis of nonspecific, chronic (>6 months) low back pain. Interventions. Both treatments consisted of 15 sessions of one hour each, twice a week including patient education. Measures. Roland Morris Disability Questionnaire to evaluate disability, and Numeric Analog Scale for pain. A score change >30% was considered clinically significant. Past treatments, use of medications, smoking habits, height, weight, profession, and physical activity were also recorded on baseline, on discharge, and 1 year after discharge (resp., T0, T1, and T2). Results. At T0 103 patients with cLBP (51 cases and 52 controls) were recruited. The treatment (T1) has been completed by 79 (T1) of which 60 then carried out the 1-year follow-up (T2). Both GPR and PT at T1 were associated with a significant statistical and clinical improvement in pain and function, compared to T0. At T2, only pain in GPR still registered a statistically significant improvement.

Oxygen uptake kinetics in older patients receiving postacute cardiac rehabilitation: effects of low-intensity aerobic training.

Molino-Lova R, Vannetti F, Pasquini G, Paperini A, Zipoli R, Polcaro P, Petrilli M, Cecchi F, Macchi C: Oxygen uptake kinetics in older patients receiving postacute cardiac rehabilitation: Effects of low-intensity aerobic training. Objective:Older patients who receive postacute cardiac rehabilitation improve their physical performance in terms of distance walked at the 6-min walk test. However, the slower and more complicated recovery, along with age-related chronic comorbidities, remarkably limits the intensity of aerobic training, which actually represents the core of cardiac rehabilitation. The aim of this study was to verify whether postacute cardiac rehabilitation also improves the cardiovascular adjustment to exercise, despite low-intensity aerobic training. Design:Using a portable gas analyzer, we assessed the O2 uptake kinetics during the 6-min walk test at the beginning and at the end of the rehabilitation in 84 patients aged 65 yrs and above. Results:All patients significantly improved the distance walked at the 6-min walk test. The comparison of the time constants of O2 uptake kinetics showed that 40% of patients also significantly improved the hemodynamic response to exercise. This improvement was independently associated with the report of sedentary lifestyle or low-intensity physical activity in the year before surgery and with longer time constants before physical training. Conclusions:Low-intensity aerobic training improves the cardiovascular adjustment to exercise selectively in patients with physical deconditioning. This confirms the notion that elderly frail patients are those who benefit most from cardiac rehabilitation.

Digital Human Models for Automated Ultrasound User Interface Design

The purpose of this theoretical paper is to describe the development of a new technology for the automated analysis and design definition of Ultrasound (US) system User Interfaces (UI) and US transducers. US examination is a real-time multi-factor approach, which involves the whole sonographer’s body; its automated evaluation, analysis and design must take into account many different factors and aspects which need to be evaluated and implemented. The proposed technology, based on Digital Human Modeling (DHM) systems, would get input from multi-factor technologies such as Motion Analysis, Eye Tracking, Superficial Electromyography, Stereo Imaging and also physical information such as temperature, ECG, respiration activity, etc., applied to different US users for different clinical applications and protocols. The utilization of DHM to manage and analyze these diverse requirements would drive the automated optimization of system design, in terms of ergonomics and workflow.

ABILITY TO WORK IN ANAEROBIC CONDITION IS ASSOCIATED WITH PHYSICAL PERFORMANCE ON THE SIX-MINUTE WALK TEST IN OLDER PATIENTS RECEIVING CARDIAC REHABILITATION

OBJECTIVE During maximal incremental exercise, the ability to work in the anaerobic condition, expressed by the respiratory exchange ratio, is associated with physical performance. Further, peak respiratory exchange ratio is regarded as the best non-invasive measure of a patients actual exercise effort. This study examined whether ability to work in the anaerobic condition is also associated with physical performance in submaximal constant work rate exercise. SUBJECTS AND METHODS A total of 75 older patients (51 men, 24 women), mean age 71.1 years (standard deviation 6.7 years), who had recently undergone cardiac surgery, performed cardiopulmonary exercise testing in a 6-min walk test before and after rehabilitation. RESULTS The distance walked, steady-state oxygen uptake, carbon dioxide output and respiratory exchange ratio increased significantly after rehabilitation (p < 0.001 for all). In multivariable models predicting the distance walked before and after rehabilitation, higher steady-state respiratory exchange ratio was independently associated with longer distance (p < 0.001 for both). CONCLUSION In older patients receiving post-acute cardiac rehabilitation the ability to work in the anaerobic condition is associated with physical performance in submaximal constant work rate exercises. Thus the steady-state respiratory exchange ratio might be regarded as a measure of the patients actual exercise effort. This information may prove useful in customizing exercise prescription and assessing the effects of rehabilitation.

The improvement of walking speed after cardiac rehabilitation is associated with the reduction in the metabolic cost of walking in older persons

BACKGROUND To walk a given distance older persons consume more metabolic energy than younger adults across all speeds. As physical activity interventions improve a variety of physical performance measures in older persons, including walking speed, in this study we hypothesized that the improvement of walking speed might be associated with the reduction of the metabolic cost of walking and we tested our hypothesis in a selected sample of older patients receiving cardiac rehabilitation. METHODS In 120 patients (88 men and 32 women, mean age 74.1 years±SD 5.0) we assessed energy expenditure during the 6-min Walk Test (6mWT) before and after the rehabilitation using a portable system for direct calorimetry. RESULTS On the 6mWT performed after the rehabilitation patients significantly increased total energy expenditure (28.0 kcal±SD 8.3 vs. 25.7 kcal±SD 7.6, p<0.001), the distance walked (398 m±SD 93 vs. 343 m±SD 95, p<0.001) and, consequently, walking speed (1.11 m/s±SD 0.26 vs. 0.95m/s±SD 0.26, p<0.001) while the metabolic cost of walking, i.e. the amount of energy used to move a body mass of 1 kg for a distance of 1m, was significantly reduced (1.00 cal/kg/m±SD 0.19 vs. 1.11 cal/kg/m±SD 0.32, p<0.001). CONCLUSIONS In older patients receiving cardiac rehabilitation the improvement of walking speed is associated with the improvement of walking economy. This might be a contributory factor to the favourable effects of physical activity interventions on physical performance measures.

Mediterranean Diet, Food Consumption and Risk of Late-Life Depression: The Mugello Study

ObjectiveTo investigate eating habits and adherence to Mediterranean Diet (MD) in relation to the risk of depression in a cohort of nonagenarians enrolled within the Mugello Study, an epidemiological study aimed at investigating both clinically relevant geriatric items and various health issues, including those related to nutritional status.DesignCross-sectional study.SettingHomes and nursing homes in the Mugello area, Florence, Italy.ParticipantsSubjects aged 90-99 years [N=388 (271F; 117M) mean age: 92.7±3.1].MeasurementsAll subjects were evaluated through questionnaires and instrumental examinations. Adherence to MD was assessed through the Mediterranean Diet Score. A shorter version of the Geriatric Depression Scale (GDS) was used to detect the possible presence of depressive symptoms. In addition, cognitive and functional status was assessed using the Mini-Mental State Examination, the Clock Drawing Test, as well as the Basic and Instrumental Activities of Daily Living test.ResultsDepressed subjects (DS) (GDS score≥5, 43.8%) were older, females and widows, than non-depressed subjects (NDS). DS reported a slightly but not statistically significant lower MD score than NDS (33.9±3.9 vs. 34.6±3.3, p=0.149). Subjects who reported to consume a greater amount of olive oil and fruit were associated with a lower risk of depression (OR=0.35, 95%CI=0.20–0.59, p<0.001 and OR=0.46, 95%CI=0.26–0.84, p=0.011, respectively) after adjustment for many possible confounders. Similar results were obtained for women, while no statistically significant differences emerged for men.ConclusionOur results support the hypothesis that a diet rich in olive oil and fruit, characteristics of MD, may protect against the development of depressive symptoms in older age.

Adherence to Mediterranean diet and nutritional status in a sample of nonagenarians

Objective: The aim is to describe the adherence to Mediterranean diet in a sample of nonagenarians and to analyse its cross‐sectional association with anthropometric and bioelectrical parameters. Design: A cross‐sectional design was employed in this study. The adherence to the Mediterranean diet was measured through the Mediterranean Diet Score (MedDietScore). Setting and participants: A representative sample of nonagenarian residents in the eight municipalities belonging to Mugello (Florence, Italy). Measurements: The tools used to investigate the nutritional status and the body composition were: weight; ulna length to estimate the height; body mass index (BMI); mid‐upper arm circumference (MUAC); calf circumference (CC); waist circumference (WC); hip circumference (HC); and specific bioelectrical impedance vector analysis (BIVAsp). Results: All the measurements were carried out for 298 nonagenarians (70.8% of whom were females). The mean value of MedDietScore was 34.3 ± 3.6. The MedDietScore was significantly correlated with CC (r = 0.127), specific resistance (Rsp, r = 0.152), and specific impedance (Zsp, r = 0.153) in the whole sample, as well as with height (r = −0.222), Rsp (r = 0.282), and Zsp (r = 0.282) in males. In the whole sample, Rsp and Zsp mean values significantly increased by quartiles of MedDietScore; these results were confirmed by vector analysis. Conclusions: The high level of adherence to Mediterranean diet could contribute to explaining the longevity of our sample. Studying the influence of dietary lifestyle in nonagenarians in depth could help to promote healthy ageing. HighlightsA few studies have explored dietary patterns and body composition in nonagenarians.In our sample, we have found a high level of adherence to Mediterranean diet.Specific resistance and specific reactance increased by quartiles of MedDietScore.Longevity can partly be attributable to a close adherence to Mediterranean diet.

Higher uric acid serum levels are associated with better muscle function in the oldest old: Results from the Mugello Study

BACKGROUND Sarcopenia is the progressive loss of muscle mass and strength that occurs with advancing age and plays a pivotal role in the causal pathway leading to frailty, disability and, eventually, to death among older persons. As oxidative damage of muscle proteins has been shown to be a relevant contributory factor, in this study we hypothesized that uric acid (UA), a powerful endogenous antioxidant, might exert a protective effect on muscle function in the oldest old and we tested our hypothesis in a group of nonagenarians who participated in the Mugello Study. METHODS 239 subjects, 73 men and 166 women, mean age 92.8years±SD 3.1, underwent the assessment of UA serum level and isometric handgrip strength, a widely used clinical measure of sarcopenia. RESULTS Mean UA serum level was 5.69mg/dL±SD 1.70 and mean handgrip strength was 15.0kg±SD 6.9. After adjusting for relevant confounders, higher UA serum levels remained independent positive predictors of isometric handgrip strength (β 1.24±SE(β) 0.43, p=0.005). CONCLUSION Our results show that higher UA serum levels are associated with better muscle function in the oldest old and, accordingly, might slow down the progression of sarcopenia.