Search Results (148)

Infants discriminate faces early in the first year, but research on infants’ discrimination of bodies is plagued by mixed findings. Using a familiarisation novelty preference method, we investigated 7- and 9-month-old infants’ discrimination of body postures presented in upright and inverted orientations, and with and without heads, along with relationships with gross and fine motor development. In our initial studies, 7-month-old infants discriminated upright headless postures with forward-facing and about-facing images. Eye tracking revealed that infants looked at the bodies of the upright headless postures the longest and at the heads of upright whole figures for 60–70% of the time regardless of the presence of faces, suggesting that heads detract attention from bodies. In a more stringent test, with similarly complex limb positions between test items, infants could not discriminate postures. With longer trials, the 7-month-olds demonstrated a familiarity preference for the upright whole figures, and the 9-month-olds demonstrated a novelty preference, albeit with a less robust effect. Unlike previous studies, we found that better gross motor skills were related to the 7-month-olds’ better discrimination of upright headless postures compared to inverted postures. The 9-month-old infants’ lower gross and fine motor skills were associated with a stronger preference for inverted compared to upright whole figures. This is further evidence of a configural representation of bodies in infancy, but it is constrained by an upper bias (heads in upright figures, feet in inverted), the test item similarity, and the trial duration. The measure and type of motor development reveals differential relationships with infants’ representations of bodies. Full article

The present study aims to investigate the multi-year effects (5 years) of individualized whole-body vibration (WBV) on locomotion, postural control, and handgrip strength in a 68-year-old man with relapse remitting multiple sclerosis (PwRRMS). The dose–response relationship induced by a single session was quantified by determining the surface electromyographic activity (sEMG) of the participant. The participant wore an orthosis to limit the lack of foot dorsiflexion in the weakest limb during walking in daily life. The gait alteration during walking was assessed at 1, 2 and 3 km/h (without the orthosis) through angle–angle diagrams by quantifying the area, perimeter and shape of the loops, and the sEMG of leg muscles was recorded in both limbs. The evaluation of postural control was conducted during upright standing by quantifying the displacement of the center of pressure (CoP). The handgrip strength was assessed by measuring the force–time profile synchronized with the sEMG activity of upper arm muscles. The participant improved his ability to walk at higher speeds (2–3 km/h) without the orthosis. There were greater improvements in the area and perimeter of angle–angle diagrams for the weakest limb (Δ = 36–51%). The sEMG activity of the shank muscles increased at all speeds, particularly in the tibialis anterior of weakest limbs (Δ = 10–68%). The CoP displacement during upright standing decreased (Δ = 40–60%), whereas the handgrip strength increased (Δ = 32% average). Over the 5-year period of intervention, the individualized WBV improved locomotion, postural control and handgrip strength without side effects. Future studies should consider the possibility of implementing an individualized WBV in PwRRMS. Full article

This study investigated the interplay of bodily degrees of freedom (DoFs) governing the collective variable comprising the center of pressure (CoP) and center of mass (CoM) in postural control through the analytical lens of multiplicative interactions across scales. We employed a task combination involving a wobble board, introducing mechanical instability mainly along the mediolateral (ML) axis and the Trail Making Task (TMT), which imposes precise visual demands primarily along the anteroposterior (AP) axis. Using Multiscale Regression Analysis (MRA), a novel analytical method rooted in Detrended Fluctuation Analysis (DFA), we scrutinized CoP-to-CoM and CoM-to-CoP effects across multiple timescales ranging from $100\mathrm{ms}$ to $10\mathrm{s}$. CoP was computed from ground reaction forces recorded via a force plate, and CoM was derived from full-body 3D motion capture using a biomechanical model. We found that the wobble board attenuated CoM-to-CoP effects across timescales ranging from $100\mathrm{to}400\mathrm{ms}$. Further analysis revealed nuanced changes: while there was an overall reduction, this encompassed an accentuation of CoM-to-CoP effects along the AP axis and a decrease along the ML axis. Importantly, these alterations in CoP’s responses to CoM movements outweighed any nonsignificant effects attributable to the TMT. CoM exhibited no sensitivity to CoP movements, regardless of the visual and mechanical task demands. In addition to identifying the characteristic timescales associated with bodily DoFs in facilitating upright posture, our findings underscore the critical significance of directionally challenging biomechanical constraints, particularly evident in the amplification of CoP-to-CoM effects along the AP axis in response to ML instability. These results underscore the potential of wobble board training to enhance the coordinative and compensatory responses of bodily DoFs to the shifting CoM by prompting appropriate adjustments in CoP, thereby suggesting their application for reinstating healthy CoM–CoP dynamics in clinical populations with postural deficits. Full article

(1) Background: The paper focuses on foot biomechanics in static situations. The aim was to determine the distribution of the load exerted by the human body on the ground in order to establish reference points on the foot for correct human body posture. (2) Methods: A model was developed to describe the body weight-ground relationship, consisting of a support platform and a part imitating the rest of the human body. Experiments consisted of tilting the general centre of gravity from the maximum forward through midfoot, a passive, neutral position, to the maximum backwards while maintaining balance. The ground load was measured in each position. (3) Results: The loads of the front and rear parts of the support platform and the resultant load force at different degrees of body tilt were calculated. It has been shown that at the maximum inclination of the body to the extreme support point, the entire weight falls on this point. For the neutral position (in the Basic Balance Point), the load on the front and rear parts of the support platform was 26% and 74%, and 40% and 60% for the passive position (in the Passive Balance Point). (4) Conclusions: The distribution of body weight on the ground is determined by the projection of the general centre of gravity on the ground through the feet. The resultant ground reaction force defines both the magnitude and direction of the load exerted on the support platform. Ground reaction forces associated with body weight were assessed at five anatomical points of the foot: the forefoot, rearfoot, midfoot, and the Passive and Basic Balance Point. In an upright standing posture, the projection of the general centre of gravity fluctuates between the Passive and Basic Balance Point, corresponding to the passive and neutral positions, respectively. Only in the neutral position, the body’s weight, as concentrated in the general centre of gravity, falls on the axis of the upper ankle joint and distributes the load between the forefoot and rearfoot. Determining the correct distribution of foot loads may serve in the future to study abnormalities in human body posture Full article

Upright-posture motorcycle crashes against steel safety barriers (SSBs) often result in severe upper-body injuries due to the sharp upper edge of the rail. While solutions for sliding crashes on curves, called a ‘motorcyclist-friendly barrier’, are already implemented in practice, protective measures for upright-posture impacts remain underdeveloped. This study systematically reviews patents and patent applications addressing upper guardrail protection for motorcyclists. We identified and analysed a small number of existing innovations aimed at mitigating the consequences of upright crashes. The selected solutions were evaluated according to their technical design, ease of installation, potential for recycling, environmental compatibility, and expected costs. Our comparative analysis reveals that while some patents or patent applications offer promising features, such as flexible caps, bent plates, or modular attachments, none comprehensively address all safety, environmental, and economic requirements. The findings provide a basis for further development of motorcyclist-friendly SSB designs and suggest specific criteria that should be included in future guidelines and standard updates. Full article

Accessible tools for post-stroke motor rehabilitation are critically needed to promote recovery beyond clinical settings. This pilot study evaluated the impact of a posture correction intervention using the Postural SmartVest, a wearable device that delivers multisensory feedback via a smartphone app. Forty individuals with post-stroke hemiparesis participated in a single supervised session, during which each patient completed the same four-phase functional protocol: multidirectional walking, free walking toward a refrigerator, an upper-limb reaching and object-handling task, and walking back to the starting point. Under the supervision of their therapists, each patient performed the full protocol twice—first without feedback and then with feedback—which allowed within-subject comparisons across multiple metrics, including upright posture duration, number and frequency of posture-related events, and temporal distribution. Additional analyses explored associations with demographic and clinical variables and identified predictors through regression models. Wilcoxon signed-rank and Mann–Whitney U tests showed significant improvements with feedback, including an increase in upright posture time ($p<0.001$), an increase in the frequency of upright posture events ($p<0.001$), and a decrease in the total task time ($p=0.038$). No significant subgroup differences were found for age, sex, lateralization, or stroke chronicity. Regression models did not identify significant predictors of improvement. Full article

Background/Objectives: Prolonged sitting is linked to musculoskeletal discomfort, yet optimal sitting posture remains poorly defined, and the consistency with which individuals reproduce specific sitting strategies is unclear. This study examined postural variability across three sitting strategies—comfortable, habitual, and correct—using three common chair types: a stool, computer chair, and ergonomic chair. Methods: Thirty healthy young adults (fifteen men, fifteen women) participated. Global sagittal joint angles—head inclination (HI), trunk angle (TA), and knee angle (KA)—were measured using a motion analysis system across five repetitions per condition. Results: The chair type significantly influenced HI and TA (p < 0.001), with ergonomic chairs encouraging more upright trunk postures. The sitting strategy significantly affected TA and KA (p < 0.01), with comfortable sitting associated with more extended angles. Women exhibited greater TA (114.8° vs. 109.0°, p < 0.001) and lower within-subject variability. Substantial postural variability was observed across all conditions, with mean ranges exceeding minimum detectable change thresholds for HI (10.3°), TA (6.9°), and KA (11.3°). Notably, correct sitting reduced KA variability compared to other strategies (p < 0.01). Conclusions: These findings highlight the individualized and variable nature of sitting posture, even under controlled instructions. The results question the reliability of memory-based seat adjustments and emphasize the need for dynamic, user-centered ergonomic design and personalized clinical guidance to support musculoskeletal health. Full article

Background/Objectives: Non-invasive spinal cord transcutaneous stimulation (scTS) has expanded the therapeutic landscape of spinal cord injury (SCI) rehabilitation, offering potential benefits beyond compensatory approaches to paralysis. Children with SCI are particularly susceptible to developing neuromuscular scoliosis due to trunk muscle paralysis and ongoing skeletal growth, making targeted interventions crucial. As demonstrated in adults and pediatrics with SCI, the ability of scTS to acutely and safely enable an upright posture and trunk control could be leveraged as a therapeutic adjunct. Activity-based locomotor training (AB-LT) alone significantly improves trunk control in children with SCIs; combining it with scTS may enhance outcomes. This pilot study evaluated the safety, feasibility, and cumulative effects of AB-LT combined with scTS on trunk control in children with SCI. Methods: Three children with SCI completed 19 to 64 sessions of combined AB-LT and scTS. Adverse effects were monitored session to session, and trunk control was assessed pre- and post-intervention. Results: Across 130 interventions in three participants, 88.5% of sessions were free from adverse effects. Reported adverse events included autonomic dysreflexia (5.4%), skin redness at electrode sites (4.6%), and headaches (1.5%). No significant impact of scTS on fatigue or central hemodynamic parameters was observed. Post-intervention, all participants demonstrated improved trunk control during quiet and perturbed sitting. Conclusions: These findings provide the first evidence supporting the safety and feasibility of this combinatorial approach in pediatric SCI rehabilitation while emphasizing the importance of monitoring skin integrity and signs of autonomic dysreflexia. This intervention shows potential synergistic benefits, warranting further research to confirm efficacy and optimize therapeutic protocols. Full article

Background: Robotic-assisted technology has become an increasingly utilized adjunct within the realm of primary total knee arthroplasty (TKA). Previous studies have shown that robotic-assisted total knee arthroplasty (raTKA) offers potential advantages of enhanced bony preparation and optimal implant alignment with equivalent long-term patient outcomes and component longevity in comparison to conventional TKA (cTKA). Furthermore, recent studies have identified the additional benefit of decreased surgeon physiologic stress with the use of raTKA. The purpose of this study was to compare differences in surgeon posture between primary raTKA and cTKA. Materials and Methods: We prospectively evaluated 103 consecutive primary TKA cases (48 raTKAs, 55 cTKAs) performed by three high-volume, fellowship-trained arthroplasty surgeons. Throughout each case, surgeons wore a posture-tracking device to evaluate time spent slouching. The threshold for slouching was set to 30 degrees of flexion from a neutral spinal axis. Demographic and operative factors were collected. Two-tailed tests and multivariate analysis were used to assess for differences between groups. Results: After controlling for individual surgeon differences in posture, we found a decrease in the percentage and duration of time spent slouching in raTKA cases compared to cTKA cases (42.4 vs. 72.5%, p < 0.001, 35.4 vs. 54.7 min, p = 0.037). On average, the use of the robot decreased surgeon slouching time by 19.3 min (26.6%, p < 0.001). Patient factors such as increased age and ASA 2 were also associated with favorable effects on posture (p < 0.001). Conclusions: Surgeons performing primary raTKA cases spend significantly less case time and case percentage in a slouched posture compared to conventional primary TKA cases. This suggests the potential for ergonomic benefit of robotic-assisted technology in primary TKA. Further research is needed to determine the long-term effects of posture on surgeon pain and career longevity. Full article

Rhythmic and artistic gymnastics expose athletes to a high risk of musculoskeletal disorders such as low back pain (LBP), often caused by repetitive and intensive training demands. This study aimed to evaluate the effects of a 12-week postural treatment using the Mézières method, focused on posture correction and vertebral movement assessed with the Spinal Mouse system, in elite rhythmic gymnasts with LBP. A randomized controlled trial with two parallel groups was conducted, comparing the Mézières method to an equivalent isostretching intervention under similar conditions. Seventeen elite gymnasts with LBP participated, receiving two weekly sessions for 12 weeks. Frontal stand posture (upright, left, and right) was measured at baseline, post-treatment, and at 2, 6, and 12 weeks using the Spinal Mouse system. The experimental group (n = 8) received Mézières therapy; the control group (n = 9) received isostretching. Significant differences in pain reduction were found between the groups (p = 0.000). In the frontal upright position, lumbar and sacral segmental angles (p = 0.021) and regional inclination (p = 0.000) also showed significant group differences. Similarly, in the frontal left position, all vertebral variables except LSpTH12 also demonstrated significant differences between the groups, with p-values ranging from 0.001 to 0.017. Both treatments reduced pain and improved flexibility, but the Mézières group showed significantly greater improvements than the isostretching group. Full article

Foot position affects postural stability during upright standing; however, conflicting indications have been reported for the ideal foot placement during stabilometric exams. The aims of this study were to evaluate (1) the correlation between anthropometric measurements (AMs) and between-feet measurements (BFMs) in self-selected comfortable foot position (SCFP) and (2) the effect of comfortable and standardized foot position (SFP) on plantar pressure and stabilometric parameters. Stabilometry was conducted on twenty healthy subjects in terms of SCFP and SFP. Correlation between AMs and BFMs in SCFP was investigated via Pearson’s analysis. Data variability was assessed using the coefficient of variation, and statistical differences between SCFP and SFP were evaluated via the Wilcoxon test. No correlation was found between AMs and BFMs. Subjects placed their feet nearly parallel in SCFP with a wider inter-heel distance. The variability of plantar pressure parameters was greater in SFP. A lower foot contact area on the right side and higher plantar pressures in the left midfoot region (p-value < 0.05) were found in SFP as compensatory foot adaptations. According to the present study, a comfortable foot position allows for the reduction in postural stability and plantar pressure parameter variability. This position may help improve statistical power when investigating statistical differences between conditions in stabilometry. Full article

Background: Our study investigated the impact of multicomponent balance exercises (MBE) and sensorimotor mobilization with foot muscle strengthening (SMFE) on postural stability in patients with balance disorders, assessed using the Balance Error Scoring System (BESS) while standing still. Methods: Twenty postoperative patients were included in a randomized clinical study and divided into an MBE group (six women and four men with an average age of 30.2 years) and the SMFE group (six women and four men aged 34.5 years). Balance was assessed with the BESS on the third postoperative day and before discharge. The hospitalization lasted 10 days. Results: All patients in both groups showed significant clinical and statistical improvements (p < 0.05) in maintaining an upright posture after the BESS test. In the MBE group, 80% of patients achieved a minimum clinically significant change of 10 points in postural stability, whereas 100% of patients in the SMFE group did the same. The SMFE group exhibited a statistically significant improvement (p < 0.05) in specific balance tasks conducted on hard and soft surfaces. Conclusions: Our patient sample results suggest that SMFE is more effective than MBE. We recommend its use in early rehabilitation, although further research is necessary. Full article

Background/Objectives: Postural control describes our ability to maintain an upright position. This study explored the impact of prolonged ankle plantar-flexed standing on postural control variability and strategy in an older adult population. The ability to perceive balance change was also assessed via subjective balance-related variables. Methods: Twenty-four community-dwelling older adults were recruited via convenience sampling. Each participant completed a balance confidence and falls efficacy questionnaire at baseline. Five barefoot quiet standing trials on a force plate then followed (Timepoint 1). After this, the participants stood with their ankles in a plantar-flexed position for up to 7.5 min before completing another quiet standing trial on the force plate. Four further ankle plantar-flexed standing trials of 2 min were then completed, interspersed with quiet standing trials on a force plate (Timepoint 2). The balance confidence and falls efficacy questionnaires were then completed again. For measures of postural control variability (sway path length, root mean square [RMS], sway area) and strategy (fractal dimension), mean values for the five trials were calculated for Timepoints 1 and 2 separately. Results: The sway path length and RMS measures were significantly increased (p < 0.05) at Timepoint 2. However, the fractal dimension did not change. There was also no change in balance confidence or falls efficacy. Conclusions: The findings suggest that prolonged standing can impact measures of postural variability without a change in postural control strategy. Postural control change also occurred without a change in subjective balance measures, suggesting that the altered balance may not be practically significant or perceptible to the individual. Full article

Background/Objectives: Upright open magnetic resonance imaging allows the impact of posture and gravity to be evaluated. Randomized controlled trials of yoga for treating urinary incontinence (UI) in women show significant clinical benefit, yet the anatomic impact of this therapy on the lower urinary tract remains unelucidated. This study tested the hypothesis that open MRI scans can be obtained with sufficient detail to visualize the bladder neck and urethra. Methods: We scanned a volunteer subject using a 0.5 Tesla MRO Open Evo scanner to obtain axial and sagittal T2-weighted pelvic scans during poses used in yoga therapy. To obtain images with the necessary detail, we employed variations in sequencing during scanning of each individual pose. The changes observed in the bladder neck and urethral outline in each pose were then compared to baseline supine images. Results: Images with sufficient anatomic detail were obtained in each of the four poses studied. These scans identified that the urethral outline changes anatomically based on the posture adopted and is dynamic with regional alternations evident in caliber during specific yoga poses. Conclusions: Open MRI can identify anatomical changes involving the bladder neck and urethra that occur during yoga poses used in the treatment of UI in women; these likely relate to effects of posture and gravity. Open MRI offers a way to elucidate the anatomic effects that specific yoga poses generate and to identify those with the potential to be most beneficial clinically to women as a form of therapy. Full article

Postural abnormalities in the sagittal plane are common in Parkinson’s disease (PD) and increase the risk of falls. Previous studies have reported short-term benefit of corrective corsets in PD patients assessed by clinical and instrumental methods, while long-term effects on sagittal posture in upright standing and during walking remain unexplored. Fifteen PD patients with postural abnormalities on the sagittal plane, evaluated via the NeuroPostureApp, and ten healthy subjects matched for age and BMI were assessed by 3D motion analysis in upright posture. Then, the PD patients were evaluated with and without the K1 Posture Keeper during standing and walking at baseline (T0) and after three months of use (T1). The results showed an anteriorization of the head–cervical region with respect to the trunk and a whole-body misalignment in PD patients compared to healthy controls. The use of the K1 Posture Keeper induced a back shift of the nasion with a better alignment of the head with respect to the trunk, pelvis, and feet in upright standing and during walking, underlining an improvement in the sagittal alignment of the entire body in PD. These findings showed the therapeutical role of K1 Posture Keeper on sagittal posture in static and dynamic conditions, potentially due to proprioceptive reorganization. Full article