Search Results (45)

Balance control in pirouettes has previously been characterized by constraint of the topple angle. However, there is a paucity of research using the margin of stability (MoS) as a dynamic measure of balance related to pirouettes. Therefore, this study aimed primarily to examine the MoS as a metric of balance during a single-turn en dehors pirouette in healthy female amateur ballet dancers. Four participants performed pirouettes until five successful pirouettes were achieved without hopping or loss of balance. Three-dimensional motion capture was used to record the motion trajectories of anatomical markers based on the Plug-in-Gait and Oxford Foot models. Motion synchronized with ground reaction forces was used to calculate the center of pressure (CoP), base of support (BoS), center of the pivot foot, center of mass (CoM), and extrapolated center of mass (XCoM) throughout the turn phase, using laboratory (LCS) and virtual left foot (LFT) coordinate systems. In the LCS and LFT coordinate system, the excursions and patterns of motion of both the CoM and XCoM relative to the CoP were similar, suggesting a neurological relationship. Two different measures of the margin of stability (MoS) in the LFT coordinate system were tabulated: the distance between the (1) XCoM and CoP and (2) XCoM and BoS center. The magnitude of both versions of the MoS was greatest at turn initiation and toe-touch, which was associated with two foot contacts. The MoS values were at a minimum approximately 50% of the stance during the turn phase: close to zero along the anteroposterior (A/P) axis and approximately 50 mm along the mediolateral (M/L) axis. On average, MoS magnitudes were reduced (mean across participants: approximately 20 mm) along the A/P axis, and larger MoS magnitudes (mean across participants: approximately 50 mm) along the M/L axis throughout the turn phase. Although all turns analyzed were completed successfully, the larger MoS values along the M/L axis suggest a fall potential. The variability between trials within a dancer and across participants and trials was documented and showed moderate inter-trial (16% to 51%) and across-participant CV% (range: 10% to 28%), with generally larger variations along the A/P axis. Although our results are preliminary, they suggest that the MoS may be useful for detecting faults in the control of dynamic balance in dehors pirouette performance, as a part of training and rehabilitation following injury. Full article

Background: Hand, foot, and mouth disease (HFMD) is a frequently self-limited viral infectious disease that affects children and has no specific antiviral treatment option. There has been increasing interest in bee products in recent years, and propolis has come to the fore due to its impressive therapeutic and protective effects. Although previous studies have shown the inhibitory effect of propolis against enteroviruses (EVs), there are no clinical data regarding its use in combatting HFMD. This prospective multicenter randomized clinical study aimed to evaluate the effect of administering propolis to children with HFMD. Methods: This study analyzed 183 children with HFMD. All children were assessed for eligibility and diagnosed with HFMD by a child health and disease specialist after presenting with symptoms of either fever, enanthem, or exanthems that had begun within the last 48 h. The patients were randomly assigned to the group receiving Anatolian propolis (n = 87) or that receiving no supplement—the control group (n = 96)—in addition to receiving symptomatic therapy as decided by the physician. The duration of the patient’s complaints, the distribution of the lesions on their body, and their fever status were recorded on admission. Parents were asked to rate the severity of their child’s restlessness, inappetence, and sleeplessness on a scale of 0–10 at their initial, second (at 48th hour), and third (after 5–7 days) visits to the hospital. The primary data analysis methods included the Kolmogorov–Smirnov test for normality and non-parametric tests such as the Kruskal–Wallis and Mann–Whitney U tests, which were used for group comparisons. Results: The median age of the patients was 28 months (range: 12–112), and the male-to-female ratio was 1:1. Most patients (62.8%) had no history of a household contact with HFMD. Intraoral lesions were present in 92.3% of patients, and 47.5% received the propolis treatment while 53.5% were in the control group. There was a significant difference between the groups in terms of their complaint scores during their second (p = 0.028) and third (p < 0.001) visits to the hospital. In addition, the mean duration of the illness in the propolis group (7.45 days) was significantly lower than that in the control group (8.58 days) (p < 0.001). No adverse effects were observed. Conclusions: Propolis has been shown to facilitate symptomatic relief and reduce the duration of the disease in children with HFMD. To better assess the efficacy of this product, which can be used safely in children, future studies supported by virological analyses are required. Full article

Background: Hallux limitus (HL) is a condition marked by the restricted dorsiflexion of the first metatarsophalangeal joint, causing pain and functional limitations, especially during the propulsive phase of walking. This restriction affects the gait, particularly in the final phase, and impairs foot stability and support. HL is more common in adults and leads to biomechanical and functional adaptations. The purpose of this study was to investigate the differences in the center of pressure between subjects with hallux limitus and those with healthy feet. Methods: A total of 80 participants (40 with bilateral HL and 40 healthy controls) aged 18 to 64 were selected from a biomechanics center at the Universidade da Coruña, Spain. The gait analysis focused on three key phases: initial contact, forefoot contact, and the loading response. Data were collected using a portable baropodometric platform and analyzed using IBM SPSS Statistics 29.0.2.0; statistical significance was set at p < 0.05, with a 95% confidence interval. Results: The gait analysis indicated that the case group exhibited statistically significant differences, showing lower values in the left foot load response during the foot contact time (77.83 ± 40.17) compared to the control group (100.87 ± 29.27) (p = 0. 010) and in the foot contact percentage (p = 0. 013) during the stance phase (10.02 ± 5.68) compared to the control group (13.05 ± 3.60). Conclusions: Bilateral HL causes subtle gait changes, with individuals showing greater contact time values in the total stance phase versus the control group. Early detection may improve quality of life and prevent complications. Full article

Introduction: Patients with cerebral palsy (CP) present mobility limitations that alter their activity and participation in social life. This study aimed to assess changes in gait kinematic measurements using the Observational Gait Scale (OGS) and preselected parameters related to the foot, knee, and hip in children with CP who received repeated BoNT-A injections within a rehabilitation treatment over a five-year follow-up period. Material and methods: This single-center retrospective observational study included 200 consecutive children with bilateral CP (GMFCS I–IV). The five-year follow-up period was analyzed. Patients received between 5 and 10 BoNT-A treatments (mean 7.6 ± 2.3), with total doses per session varying from 20 units/kg to 30 units/kg for ABOBoNT-A and from 10 units/kg to 20 units/kg for OnaBoNT-A. In most cases, multilevel injections were performed, including in the hip flexors and adductors, knee flexors, and foot plantar flexors. Results: The mean age of the patients at the beginning was 32.23 months (±6.96). The OGS score improved in 74.5% and 76.5% of the patients, and deterioration occurred in 8.5% and 7% of patients for the right and left lower extremities, respectively. The changes in the OGS typically ranged from 1 to 4 points. Significant improvements in the knee position at midstance, initial foot contact, foot contact at midstance, timing of heel rise, and knee and hip positions at terminal stance were observed. Conclusions: The data from our retrospective observational study show a significant, long-term, positive effect of integrated treatment on gait kinematics in patients with CP in a homogenous group of young children with bilateral spastic cerebral palsy. Full article

This study investigates the benefits of innovative full-contact insoles, crafted using polyester fabric sheets of thermoplastic extruded materials, for individuals with hallux valgus-induced plantar pain. Thirty-five individuals with hallux valgus-induced foot pain were randomly allocated to either the experimental group, wearing innovative full-contact insoles 6 h daily, or the control group, using regular foot insoles, over a period of 12 weeks. Data collection occurred at baseline, and at 1 week, 2 months, and 3 months after the initial fitting. Results indicated that the innovative full-contact insoles significantly reduced anteroposterior displacement by an average of 0.9 cm (p = 0.025) and displacement area by 0.79 cm² (p = 0.012). Gait improvements included an increase in the swing phase (36.46%, p = 0.008) and a reduction in stance phase duration (63.54%, p = 0.019). Pressure peaks at critical foot regions like the second metatarsal and medial heel were reduced by up to 39.45 kPa (p = 0.016) and 104.07 kPa (p = 0.031), while contact areas in the midfoot increased by 6.17 cm² (p = 0.039). Foot pain decreased by an average score of 1.28 points on a 10-point scale across various measures (p = 0.041). These findings suggest that the innovative full-contact insoles effectively enhance pressure distribution and gait dynamics in patients with hallux valgus, providing a viable option for managing foot discomfort. Full article

Background/Objectives: Post-stroke hemiparetic gait often presents with asymmetric patterns to compensate for stability deficits. This study examines gait differences in chronic stroke patients with spastic hemiparesis based on initial foot contact type—forefoot versus rearfoot. Methods: Thirty-four independently walking spastic hemiparetic patients were retrospectively analyzed. Using 3D gait analysis, patients were categorized by initial contact type. Spatiotemporal descriptors, joint kinematics, kinetics, and EMG patterns were compared across groups. Results: Patients with rearfoot initial contact (G1) showed higher cadence, longer single-limb support time and shorter stride times than those with forefoot contact (G0). G1 patients also demonstrated greater knee flexion during stance, enhancing stability. Additionally, G1 patients with abnormal lateral gastrocnemius activation in the swing phase showed increased ankle power at the end of the stance phase. Conclusions: In post-stroke spastic hemiparetic patients, the type of initial foot contact—forefoot or rearfoot—appears to influence gait characteristics, with rearfoot contact associated with a trend toward improved gait parameters, such as increased cadence and longer single-limb support. Full article

Instrumented gait analysis is widely used in clinical settings for the early detection of neurological disorders, monitoring disease progression, and evaluating fall risk. However, the gold-standard marker-based 3D motion analysis is limited by high time and personnel demands. Advances in computer vision now enable markerless whole-body tracking with high accuracy. Here, we present vGait, a comprehensive 3D gait assessment method using a single RGB-D sensor and state-of-the-art pose-tracking algorithms. vGait was validated in healthy participants during frontal- and sagittal-perspective walking. Performance was comparable across perspectives, with vGait achieving high accuracy in detecting initial and final foot contacts (F1 scores > 95%) and reliably quantifying spatiotemporal gait parameters (e.g., stride time, stride length) and whole-body coordination metrics (e.g., arm swing and knee angle ROM) at different levels of granularity (mean, step-to-step variability, side asymmetry). The flexibility, accuracy, and minimal resource requirements of vGait make it a valuable tool for clinical and non-clinical applications, including outpatient clinics, medical practices, nursing homes, and community settings. By enabling efficient and scalable gait assessment, vGait has the potential to enhance diagnostic and therapeutic workflows and improve access to clinical mobility monitoring. Full article

This study investigated the collapse of the medial longitudinal arch (MLA) as a risk factor for medial tibial stress syndrome (MTSS), hypothesizing that overuse of extrinsic foot muscles to prevent MLA collapse can lead to disability. Twenty healthy adults (age: 20.8 ± 0.8, height: 162.2 ± 10.4, weight: 54.9 ± 9, BMI: 20.8 ± 1.7) (39 feet) with a foot posture index score below 6 and no recent lower extremity orthopedic history participated. Ultrasonography measured foot muscle cross-sectional areas, while three-dimensional motion analysis using VICON assessed foot kinematics during gait, focusing on navicular height at initial contact (ICNH) and dynamic navicular drop (DND) during the stance phase. Hierarchical cluster analysis based on ICNH and DND compared muscle cross-sectional areas between clusters using ANOVA or Kruskal–Wallis test. The analysis indicated that ICNH was lower in clusters 1 and 3 than in cluster 2, and DND was smaller in clusters 1 and 2 than in cluster 3. Although there was no significant difference in muscle cross-sectional area between the clusters, the flexor hallucis longus tended to be thicker in cluster 1 than in cluster 3 (p = 0.051). The findings suggest that flexor digitorum longus may help prevent MLA compression during loading, indicating that overuse of extrinsic foot muscles may contribute to MTSS development. Full article

The effects of occlusal splints on sport performance have already been studied, although their biomechanical impacts are often overlooked. We investigated the kinematical changes during running until exhaustion at severe intensity while wearing a mandibular advancement occlusal splint. Twelve trained runners completed (i) an incremental protocol on a track to determine their velocity corresponding to maximal oxygen uptake and (ii) two trials of square wave transition exercises at their velocity corresponding to maximal oxygen until exhaustion, wearing two occlusal splints (without and with mandibular advancement). Running kinematics were compared within laps performed during the square wave transition exercises and between splint conditions. The mandibular advancement occlusal splint increased the running distance covered (~1663 ± 402 vs. 1540 ± 397 m, p = 0.03), along with a noticeable lap effect in decreasing stride frequency (p = 0.04) and increasing stride length (p = 0.03) and duty factor (p < 0.001). No spatiotemporal differences were observed between splints, except for improved balance foot contact times in the mandibular advancement condition. An increased knee flexion angle at initial contact (p = 0.017) was noted along laps in the non-advancement condition, despite the fact that no differences between splints were found. Running patterns mainly shifted within laps rather than between conditions, indicating that a mandibular advancement occlusal splint had a trivial kinematical effect. Full article

There is limited validation for portable methods in evaluating high-speed running biomechanics, with inertial measurement unit (IMU) systems commonly used as wearables for this purpose. This study aimed to evaluate the validity of an IMU system in high-speed running compared to a 3D motion analysis system (MAS). One runner performed incremental treadmill running, from 12 to 18 km/h, on two separate days. Sagittal angles for the shank, knee, hip and pelvis were measured simultaneously with three IMUs and the MAS at the point of contact (POC), the timing when the foot initially hits the ground, as identified by IMU system acceleration, and compared to the POC identified via force plate. Agreement between the systems was evaluated using intra-class correlation coefficients, Pearson’s r, Bland–Altman limits of agreements, root mean square error and paired t-tests. The IMU system reliably determined POC (which subsequently was used to calculate stride time) and measured hip flexion angle and anterior pelvic tilt accurately and consistently at POC. However, it displayed inaccuracy and inconsistency in measuring knee flexion and shank angles at POC. This information provides confidence that a portable IMU system can aid in establishing baseline running biomechanics for performance optimisation, and/or inform injury prevention programs. Full article

Background: This study aims to assess the impact of safety footwear (SF) on workers concerning foot-related problems, especially regarding discomfort, foot pain, and skin lesions. Methods: A literature search of PubMed, Embase, Scopus, and Cochrane databases was performed according to PRISMA guidelines. Studies reporting foot-related problems in workers wearing SF were included. Exclusion criteria included non-English papers, reviews, laboratory and animal studies, expert opinions, letters to the editor, and grey literature. The quality assessment was performed using the Newcastle–Ottawa Scale. Descriptive statistic was used to present data. Result: The initial search results yielded 483 articles; 7 articles were included in the review process. Despite the extensive variety of SF, all studies consistently reported symptomatic discomfort and pain. The discomfort factors included heat, sweating, heaviness, and footwear flexibility, with primary issues in the toes, toecaps, or metatarsal–toe crease region. The pain prevalence ranged from 42.3% to 60.8% in various anatomical regions. Irritant Contact Dermatitis was the most common (97.9%) foot dermatosis, but other foot lesions were reported: dry skin (30.2%), calluses (30%), hard nails (28%), corns (27%), and blisters. Conclusions: Current SFs are designed to comply with safety regulations but are influenced by the frequent occurrence of discomfort and foot problems. The literature review identified weaknesses in certain design features. Recommendations have been proposed to improve SF development. These include addressing issues such as the selection of specific types and designs of SF based on task performance and the working environment, footwear weight, and breathable materials for moisture permeation. Considerations should also encompass distinct sizing for an optimal fit, insole application, especially for prolonged standing users, and education programs to prevent foot-related issues. Full article

Background: This research investigates the biomechanical impact of the split-step technique on forehand and backhand lunges in badminton, aiming to enhance players’ on-court movement efficiency. Despite the importance of agile positioning in badminton, the specific contributions of the split-step to the biomechanical impact of lunging footwork still need to be determined. Methods: This study examined the lower limb kinematics and ground reaction forces of 18 male badminton players performing forehand and backhand lunges. Data were collected using the VICON motion capture system and Kistler force platforms. Variability in biomechanical characteristics was assessed using paired-sample t-tests and Statistical Parametric Mapping 1D (SPM1D). Results: The study demonstrates that the split-step technique in badminton lunges significantly affects lower limb biomechanics. During forehand lunges, the split-step increases hip abduction and rotation while decreasing knee flexion at foot contact. In backhand lunges, it increases knee rotation and decreases ankle rotation. Additionally, the split-step enhances the loading rate of the initial ground reaction force peak and narrows the time gap between the first two peaks. Conclusions: These findings underscore the split-step’s potential in optimizing lunging techniques, improving performance and reducing injury risks in badminton athletes. Full article

Gait event detection is essential for controlling an orthosis and assessing the patient’s gait. In this study, patients wearing an electromechanical (EM) knee–ankle–foot orthosis (KAFO) with a single IMU embedded in the thigh were subjected to gait event detection. The algorithm detected four essential gait events (initial contact (IC), toe off (TO), opposite initial contact (OIC), and opposite toe off (OTO)) and determined important temporal gait parameters such as stance/swing time, symmetry, and single/double limb support. These gait events were evaluated through gait experiments using four force plates on healthy adults and a hemiplegic patient who wore a one-way clutch KAFO and a pneumatic cylinder KAFO. Results showed that the smallest error in gait event detection was found at IC, and the largest error rate was observed at opposite toe off (OTO) with an error rate of −2.8 ± 1.5% in the patient group. Errors in OTO detection resulted in the largest error in determining the single limb support of the patient with an error of 5.0 ± 1.5%. The present study would be beneficial for the real-time continuous monitoring of gait events and temporal gait parameters for persons with an EM KAFO. Full article

With the conventional mechanical rotation measurement of joints, only static measurements are possible with the patient at rest. In the future, it would be interesting to carry out dynamic rotation measurements, for example, when walking or participating in sports. Therefore, a measurement method with an elastic polymer-based capacitive measuring system was developed and validated. In our system, the measurement setup was comprised of a capacitive strain gauge made from a polymer, which was connected to a flexible printed circuit board. The electronics integrated into the printed circuit board allowed data acquisition and transmission. As the sensor strip was elongated, it caused a change in the spacing between the strain gauge’s electrodes, leading to a modification in capacitance. Consequently, this alteration in capacitance enabled the measurement of strain. The measurement system was affixed to the knee by adhering the sensor to the skin in alignment with the anterolateral ligament (ALL), allowing the lower part of the sensor (made of silicone) and the circuit board to be in direct contact with the knee’s surface. It is important to note that the sensor should be attached without any prior stretching. To validate the system, an in vivo test was conducted on 10 healthy volunteers. The dorsiflexion of the ankle was set at 2 Nm using a torque meter to eliminate any rotational laxity in the ankle. A strain gauge sensor was affixed to the Gerdii’s tubercle along the course of the anterolateral ligament, just beneath the lateral epicondyle of the thigh. In three successive measurements, the internal rotation of the foot and, consequently, the lower leg was quantified with a 2 Nm torque. The alteration in the stretch mark’s length was then compared to the measured internal rotation angle using the static measuring device. A statistically significant difference between genders emerged in the internal rotation range of the knee (p = 0.003), with female participants displaying a greater range of rotation compared to their male counterparts. The polymer-based capacitive strain gauge exhibited consistent linearity across all measurements, remaining within the sensor’s initial 20% strain range. The comparison between length change and the knee’s internal rotation angle revealed a positive correlation (r = 1, p < 0.01). The current study shows that elastic polymer-based capacitive strain gauges are a reliable instrument for the internal rotation measurement of the knee. This will allow dynamic measurements in the future under many different settings. In addition, significant gender differences in the internal rotation angle were seen. Full article

Background: The objective of this study was to investigate the impact of a customized exercise program on electromyographic (EMG) variables during side-cutting maneuvers. Methods: Fifty-seven physically active volunteers were recruited and randomized into two groups: a control group (CG) and an experimental group (EG). The CG maintained their regular physical activity, while the EG followed an individualized, integrated exercise regimen that included strength, neuromuscular, proprioceptive, eccentric training, and whole-body vibration (WBV) exercises, lasting for 12 weeks. EMG-Root Means Square (RMS) values for the quadriceps (Q) and hamstrings (H) were measured immediately following initial foot contact at 50, 100, 150, and 200 milliseconds. Changes in EMG activity were evaluated before and after a twelve-week intervention, and the effect size (ES, 90% confidence limit [90%CL]) was calculated. Results: The results showed that the EG participants exhibited enhanced co-contraction as measured by the hamstring/quadriceps ratio (H/Q ratio) during both open and cross-cutting side maneuvers after the twelve-week intervention. Conclusion: Furthermore, the customized, integrated exercise program that combined strength, neuromuscular, proprioceptive, eccentric training, and WBV exercises were could potentially serve as a beneficial neuromuscular and biomechanical strategy for addressing knee injury risk in non-professional, physically active populations at high risk for such injuries. Full article