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.

Effects of obesity on gait pattern in young individuals with Down syndrome.

In individuals with Down syndrome (DS), the prevalence of obesity is widespread; despite this, there are no experimental studies on the effect of obesity on gait strategy in DS individuals. The aim of this study is to assess the clinical gait analysis of a group of obese individuals with DS and a group of nonobese individuals with DS to determine whether obesity produces a different gait pattern in these participants. In addition, although females and males share a similar mass, they are characterized by different fat distribution and/or accumulation; thus, the presence of differences between females and males within the two DS groups was investigated. Gait analysis data of a group of 78 young individuals with DS and 20 normal-weight participants in the 5-18-year age range were considered. Among DS individuals, 40 were classified as obese (obese DS group), whereas 38 were classified as normal weight (nonobese groups). A three-dimensional gait analysis was carried out using an optoelectronic system, force platforms and video recording. Spatiotemporal, kinematic and kinetic parameters were identified and calculated for each participant. Our results show that most of the parameters were similar in the two groups of DS participants; the only differences were in terms of stance duration, longer in the obese DS group and dorsiflexion ability during the swing phase, which was limited in the obese DS group. The two DS groups were significantly different in terms of ankle stiffness (Ka index): both groups were characterized by reduced values compared with the control group, but the obese group presented lower values with respect to nonobese participants. The data showed that females were characterized by significant modifications of gait pattern compared with males in both groups, in particular, at proximal levels, such as the hip and the pelvis. Our findings indicate that the presence of obesity exerts effects on gait pattern in DS individuals and in particular on ankle joint stiffness. These results may have special clinical relevance; the biomechanical comparison of gait in young obese and nonobese DS individuals may provide a basis for developing either specific or common rehabilitative strategies.

Quantification of long-term effects of botulinum injection in a case of cerebral palsy affecting the upper limb movement.

OBJECTIVE: The aim of this work was to put into evidence the long-lasting modification induced by botulinum toxin injection and rehabilitative treatment on motor control. METHODS: In this contribution, we report the case of a female child showing hemiplegia, due to cerebral palsy. She underwent botulinum injection, followed by physical and occupational therapy. We quantified the biomechanical, cerebral and occupational aspects of her impaired upper limb, also dynamically, with respect to her pre- and post-treatment condition. RESULTS: Small long-lasting improvements--induced on biomechanics by botulinum injection--triggered wide cerebral modification, well reflected in improved contextual movements and motor strategy. CONCLUSION: These results provide evidences that small modifications in the end-effector performance often imply cerebral modifications and improvement in finalized motor strategy.

Mechanical energy assessment of adult with Down syndrome during walking with obstacle avoidance.

The aim of this study is analyzing the differences between plane walking and stepping over an obstacle for two groups of healthy people and people with Down syndrome and then, evaluating the movement efficiency between the groups by comprising of their mechanical energy exchanges. 39 adults including two groups of 21 people with Down syndrome (age: 21.6 ± 7 years) and 18 healthy people (age: 25.1 ± 2.4 years) participated in this research. The test has been done in two conditions, first in plane walking and second in walking with an obstacle (10% of the subject's height). The gait data were acquired using quantitative movement analysis, composed of an optoelectronic system (Elite2002, BTS) with eight infrared cameras. Mechanical energy exchanges are computed by dedicated software and finally the data including spatiotemporal parameters, mechanical energy parameters and energy recovery of gait cycle are analyzed by statistical software to find significant differences. Regards to spatiotemporal parameters velocity and step length are lower in people with Down syndrome. Mechanical energy parameters particularly energy recovery does not change from healthy people to people with Down syndrome. However, there are some differences in inter-group through plane walking to obstacle avoidance and it means people with Down syndrome probably use their residual abilities in the most efficient way to achieve the main goal of an efficient energy recovery.

The fractal dimension approach in posture: a comparison between Down and Prader-Willi syndrome patients.

The suitability of new dynamic system analysis was investigated to compare postural control in Prader-Willi syndrome (PWS) and Down syndrome (DS) patients. Time-domain, frequency-domain parameters and fractal dimension (FD) of centre of pressure (CoP) were computed in maintaining normal standing on a force platform in 20 DS and 13 PWS patients, compared to 26 obese (obese control group, OCG) and 20 healthy individuals (healthy control group, HCG). DS and PWS showed greater displacements along both directions and longer sway path (SP) parameter than HCG and OCG, with statistical differences between PWS and DS for anteroposterior displacement and SP. DS used higher frequency strategy when compared to PWS, OCG and HCG. Both DS and PWS were characterised by greater values of FD than OCG and HCG, with higher values in DS. The analyses in frequency domain and of the dynamic nature of CoP suggest that DS patients are characterised by a more complex and irregular signal than PWS patients.

Feedback reliance during an arm-tapping task with obstacle avoidance in adults with Down syndrome.

Optimal movement control reflects a combination of both feedback and feedforward processes. However, as motor control evolves, feedforward mechanisms become prevailing respect to feedback-based movements, and less reliance on sensory information leads to a decreased number of corrections in the trajectory. In subjects with Down syndrome (DS), the study of the wrist's trajectory during an arm-tapping task revealed feedback-based corrections designed to reduce the degree of discrepancy between the position of the limb and the target, leading to the assumption that performers with DS have problems with movement planning and feedforward control. The present study was aimed at expanding the evidence about motor control in DS by evaluating the influence of a perturbing factor (an obstacle) on motor control strategies during an arm-tapping task and to clarify if the presence of an obstacle elicited a higher reliance on feedback control in controls and in DS. Sixteen right-handed adults with DS and 21 right-handed, age-matched control subjects (N) were evaluated by means of quantitative motion analysis. The results suggest that the presence of an obstacle elicited changes in the motor strategies of both DS and N, with a destabilizing effect that led subjects to rely more on feedback control. DS showed some aspects of movement efficiency that were in accordance with N strategies, but the prevailing factor of optimization in these subjects remained safety. A focused rehabilitation could help DS subjects to develop more efficient motor strategies in the presence of motor uncertainty and perturbations.

Motor strategies and motor programs during an arm tapping task in adults with Down Syndrome.

Slow movements and atypical patterns of muscle activation are well-known features of Down Syndrome (DS). Some studies attribute these features to a deficit in voluntary motor commands and preprogramming of actions, that lead subjects with DS to be more reliant on feedback control. In the present study, we evaluated the movement strategies of 13 adult subjects with DS and of 22 age-matched controls (N) during an arm tapping task. By means of quantitative motion analysis, our aim was to describe movement differences in DS respect to typical population and provide a means of interpreting such differences in terms of the underlying different control processes. The results highlighted distinct motor strategies for the tapping task in the two groups, with DS relying more on the trunk motion and N relying on the elbow motion to accomplish the task. Furthermore, DS corrected their wrist trajectory more than N subjects, giving shape to multi-peaked velocity profiles. Longer duration of the trials and a higher index of curvature were found in DS. The results suggest that subjects with DS rely more on feedback control, whereas they have problems with movement planning and feed-forward control. The different strategy operated by subjects with DS leads to a different task performance.

Obstacle avoidance in Down syndrome.

INTRODUCTION: The ability to avoid obstacles requires to represent the properties of the obstacle, represent the location of the obstacle relative to the body and update these representations as the body moves. Individuals with Down syndrome (DS) often have trouble avoiding obstacles, leading to increased frequency of trips and falling. The aim of the present study was to deeply analyze obstacle avoidance strategies in normally developed young adults (N) and in young adults with DS, at different levels of obstacle heights, with particular attention to the strategies used for clearing the obstacle and to how the walking pattern was modified by obstacle perception. METHODS: 10 DS and 16 age-matched N walked along a walkway in three conditions: plain walking, walking with obstacle at ground level, walking with obstacle at 10% of the subject's height. Spatiotemporal parameters were analyzed. RESULTS: There was evidence for a different avoidance strategy in DS, and for a difficulty in regulating gait parameters when challenged with a complex situation as the presence of an obstacle. This may lead to an increased risk of fall. The results in addition suggested a lack in anticipatory movement adjustments in DS and provided further evidence of the presence of difficulties in perceptual-motor coupling in DS.

Measuring regularity of human postural sway using approximate entropy and sample entropy in patients with Ehlers-Danlos syndrome hypermobility type.

Ligament laxity in Ehlers-Danlos syndrome hypermobility type (EDS-HT) patients can influence the intrinsic information about posture and movement and can have a negative effect on the appropriateness of postural reactions. Several measures have been proposed in literature to describe the planar migration of CoP over the base of support, and the most used in clinical field are the CoP excursions in antero-posterior and medio-lateral direction. In recent years a growing number of studies have been designed to explore the complexity of the COP trajectories during quiet standing. We assessed 13 adults with EDS-HT (EDSG) and 20 healthy adults (CG) during static posture, evaluating the CoP using time and frequency domain analysis and entropy analysis (SampEn and ApEn parameters). Higher values of CoP displacements in medio-lateral and anterior-posterior directions for EDSG than CG were found; no differences were observed in CoP frequency. The entropy analysis showed lower value for EDSG than CG, pointing out the needing of EDSG to concentrate more attention on postural control, loosing complexity and reflecting a less automatized postural control.

Movement analysis and EEG recordings in children with hemiplegic cerebral palsy.

Impaired hand function is often the most disabling symptom in children with hemiplegic cerebral palsy (CP). Literature provides a wide number of studies dealing either with the kinematics or the cerebral correlates of the impairment. Nevertheless, few studies exist merging both aspects together. The aim of this study is the integrated analyses of time and spatial parameters of both the affected and less-affected sides and of the EEG signal, recorded during the movement execution, for the quantitative description of the pointing gesture in children with CP. The participants (pathological and control subjects) were asked to execute a pointing task simultaneously with the recording by an optoelectronic system and an electroencephalographer. Kinematic data were processed for the extraction of several synthetic indexes, to be correlated with parameters derived from frequency analysis of the electroencephalographic signal. Kinematic results showed statistical differences (1) between the affected and the less-affected arms in patients and (2) between the less-affected arm in patients and the normal arm in controls. Further differences were found in kinematics with respect to bilateral or ipsilateral motor control, extracted from EEG. Given the different behavior evidenced by either ipsilateral or contralateral reorganization, and considering the role of feedback and feed-forward contributions to motor programming, some hypotheses emerged about the motor control during pointing task in CP.

Quantitative evaluation of facial movement and morphology.

OBJECTIVES: The aim of our study was to quantitatively analyze facial motion kinematics by means of an optoelectronic system. In particular, we defined a set of easily recognizable reference points for markerization, and tested the applicability of our markerization method for an exhaustive characterization of the subjects' facial motion through the definition of some kinematic parameters. METHODS: Thirty healthy subjects (mean age, 24.6 +/- 1.0 years; 15 female and 15 male) participated in the study. A set of markers (diameter, 3 mm) was positioned on several reference points of the face, and some parameters were computed for the characterization of facial morphology and movement, such as ranges of motion, angles, times, and distances. RESULTS: The protocol was tested for inter-rater and intra-rater reliability by use of intraclass correlation, of which the results were good (between 0.4 and 0.75) to excellent (greater than 0.75). The parameters were useful for characterizing the resting position, mimicry, and speaking movements, and highlighted some distinctions between men and women in facial morphology. CONCLUSIONS: The protocol can be applied to a variety of facial movements, including speaking. Future works could address the use of the protocol in subjects with disorders and the integrated analysis of kinematic parameters and voice spectrography.

Gait strategy in patients with Ehlers-Danlos syndrome hypermobility type and Down syndrome.

People suffering from Ehlers-Danlos syndrome (EDS) hypermobility type present a severe ligament laxity that results in difficulties in muscle force transmission. The same condition is present in people suffering from Down syndrome (DS) even if their clumsy movements are due to cerebral and cognitive impairments. The aim of this study was to quantify the gait patterns of subjects with EDS and with DS using Gait Analysis (GA). We quantified the gait strategy in 12 EDS individuals and in 16 participants with DS. Both pathological groups were compared to 20 age-matched healthy controls in terms of kinematics and kinetics. Results showed that DS individuals are characterized by a more compromised gait pattern than EDS participants, even if both groups are characterized by joint hypermobility. All the patients showed significant decreased of ankle stiffness probably due to congenital hypotonia and ligament laxity, while different values of hip stiffness. These findings help to elucidate the complex biomechanical changes due to joint hypermobility and may have a major role in the multidimensional evaluation and tailored management of these patients.

Spatiotemporal and kinematic aspects of obstacle avoidance in subjects with Down syndrome.

Obstacle avoidance studies have been extensively performed in normally developed subjects (N), but little work has been done on the characterization of this task in subjects with Down syndrome (DS). The aim of this study was to describe the management of walking with obstacle avoidance in adults with DS and in age-matched N subjects, considering both the lower and upper limbs. Ten subjects with DS and 16 N subjects were evaluated. The subjects walked along a walkway in two conditions: level, unobstructed walking and walking with an obstacle. The tasks were acquired using three-dimensional quantitative movement analysis. Spatiotemporal and kinematic parameters for the trunk, upper limbs and lower limbs were analyzed. The results demonstrated that the presence of a destabilizing element, the obstacle, enhanced different motor strategies in DS compared with N subjects, as shown by the parameters of the lower limbs, with a stabilization and safety strategy adopted at the upper limbs in DS.

Fractal dimension approach in postural control of subjects with Prader-Willi Syndrome.

BACKGROUND: Static posturography is user-friendly technique suitable for the study of the centre of pressure (CoP) trajectory. However, the utility of static posturography in clinical practice is somehow limited and there is a need for reliable approaches to extract physiologically meaningful information from stabilograms. The aim of this study was to quantify the postural strategy of Prader-Willi patients with the fractal dimension technique in addition to the CoP trajectory analysis in time and frequency domain. METHODS: 11 adult patients affected by Prader-Willi Syndrome (PWS) and 20 age-matched individuals ( CONTROL GROUP: CG) were included in this study. Postural acquisitions were conducted by means of a force platform and the participants were required to stand barefoot on the platform with eyes open and heels at standardized distance and position for 30 seconds. Platform data were analysed in time and frequency domain. Fractal Dimension (FD) was also computed. RESULTS: The analysis of CoP vs. time showed that in PWS participants all the parameters were statistically different from CG, with greater displacements along both the antero-posterior and medio-lateral direction and longer CoP tracks. As for frequency analysis, our data showed no significant differences between PWS and CG. FD evidenced that PWS individuals were characterized by greater value in comparison with CG. CONCLUSIONS: Our data showed that while the analysis in the frequency domain did not seem to explain the postural deficit in PWS, the FD method appears to provide a more informative description of it and to complement and integrate the time domain analysis.

Gait pattern in two rare genetic conditions characterized by muscular hypotonia: Ehlers-Danlos and Prader-Willi syndrome.

This study aimed to quantify and compare the gait pattern in Ehlers-Danlos (EDS) and Prader-Willi syndrome (PWS) patients to provide data for developing evidence-based rehabilitation strategies. Twenty EDS and 19 PWS adult patients were evaluated with an optoelectronic system and force platforms for measuring kinematic and kinetic parameters during walking. The results were compared with those obtained in a group of 20 normal-weight controls (CG). The results showed that PWS patients walked with longer stance duration and reduced velocity than EDS, close to CG. Both EDS and PWS showed reduced anterior step length than CG. EDS kinematics evidenced a physiological position at proximal joints (pelvis and hip joint) while some deficits were displayed at knee (reduced flexion in swing phase) and ankle level (plantar flexed position in stance and reduced dorsal flexion in swing). PWS showed a forward tilted pelvis in the sagittal plane, excessive hip flexion during the whole gait cycle and an increased hip movement in the frontal plane. Their knees were flexed at initial contact with reduced range of motion while ankle joints showed a plantar flexed position during stance. No differences were found in terms of ankle kinetics and joint stiffness. Our data showed that EDS and PWS patients were characterized by a different gait strategy: PWS showed functional limitations at every level of the lower limb joints, whereas in EDS limitations, greater than PWS, were reported mainly at the distal joints. PWS patients should be encouraged to walk for its positive impact on muscle mass and strength and energy balance. For EDS patients the rehabilitation program should be focused on ankle strategy improvement.

Gait strategy in patients with Ehlers-Danlos syndrome hypermobility type: a kinematic and kinetic evaluation using 3D gait analysis.

The aim of this study was to quantify the gait patterns of adults with joint hypermobility syndrome/Ehlers-Danlos syndrome (JHS/EDS-HT) hypermobility type, using Gait Analysis. We quantified the gait strategy in 12 JHS/EDS-HT adults individuals (age: 43.08+6.78 years) compared to 20 healthy controls (age: 37.23±8.91 years), in terms of kinematics and kinetics. JHS/EDS-HT individuals were characterized by a non-physiological gait pattern. In particular, spatio-temporal parameters evidenced lower anterior step length and higher stance phase duration in JHS/EDS-HT than controls. In term of kinematics, in JHS/EDS-HT patients the main gait limitations involved pelvis, distal joints and ankle joint. Conversely, hip and knee joint showed physiological values. Ankle moment and power revealed reduced peak values during terminal stance. Differences in stiffness at hip and ankle joints were found between JHS/EDS-HT and controls. JHS/EDS-HT patients showed significant decreased of Kh and Ka parameters very probably due to congenital hypotonia and ligament laxity. These findings help to elucidate the complex biomechanical changes in JHS/EDS-HT and may have a major role in the multidimensional evaluation and tailored management of these patients.

The effects of muscle hypotonia and weakness on balance: a study on Prader-Willi and Ehlers-Danlos syndrome patients.

Prader-Willi syndrome (PWS) and Ehlers-Danlos syndrome (EDS) are two different genetical disorders both characterized, among other features, by muscular hypotonia. Postural control seems to be impaired in both conditions. The aim of the present study was to quantitatively compare postural control in adult PWS and EDS using stabilometric platform to unveil possible common determinants of impaired balance. We enrolled 11 PWS and 21 EDS adult patients and 20 age-matched controls. They were instructed to maintain an upright standing position for 30s with open eyes (OEs) focusing on a 6 cm black circle positioned at a distance of 1.5m. Both PWS and EDS patients were characterized by higher RANGEML, RANGEAP and trajectory length of CoP values as compared to CG. No statistically differences were found between PWS and EDS in terms of any of these parameters. The results demonstrated that both PWS and EDS are characterized by a severe postural instability. Muscle hypotonia and weakness may account for reduced balance capacity. Quantitative characterization of instability is important to identify, develop and enhance rehabilitation interventions.

A new approach for the quantitative evaluation of drawings in children with learning disabilities.

A new method for a quantitative and objective description of drawing and for the quantification of drawing ability in children with learning disabilities (LD) is hereby presented. Twenty-four normally developing children (N) (age 10.6 ± 0.5) and 18 children with learning disabilities (LD) (age 10.3 ± 2.4) took part to the study. The drawing tasks were chosen among those already used in clinical daily experience (Denver Developmental Screening Test). Some parameters were defined in order to quantitatively describe the features of the children's drawings, introducing new objective measurements beside the subjective standard clinical evaluation. The experimental set-up revealed to be valid for clinical application with LD children. The parameters highlighted the presence of differences in the drawing features of N and LD children. This paper suggests the applicability of this protocol to other fields of motor and cognitive valuation, as well as the possibility to study the upper limbs position and muscle activation during drawing.

Postural control in children, teenagers and adults with Down syndrome.

The goal of this work was to analyze postural control in Down syndrome (DS) participants considering three different groups composed by children, teenagers and adults with DS. An analysis of the centre of pressure (COP) displacement during standing position was therefore performed for the three groups of subjects. The obtained signal of COP was then analyzed in both time and frequency domains in order to perform a thorough analysis of the signal. Even if several parameters revealed more differences between the control and DS participants in adulthood, results indicated a divergence of these two groups starting from their early age, although the limit of this study considering a cross-sectional, and not a longitudinal comparison. In particular, COP medio-lateral range of motion pointed out a decrease for both groups considered (pathological and control) in time domain analysis that could lead to the same conclusion in developing strategies, but frequency domain analysis evidenced how this result is reached by the different population: DS people showed a larger frequency of movement in ML more evidenced in adults group (Down Syndrome Adults Group vs. Adults Control Group; 0.35 ± 0.22 Hz vs. 0.17 ± 0.15 Hz; p < 0.05). Even if less pronounced also for the other parameters computed these differences emerged. Aims for the two macro-groups, DS and CG, are different: DS people focused on overcoming the lack of equilibrium caused by hypotonia and ligament laxity, while control group attempted to improve their strategy in term of efficiency, pointing out a different strategy development.