Acta of Bioengineering and Biomechanics

The aim of this study was to examine a short-term fluoride ions release from selected materials - resin-modified glass ionomer -Vitremer (3M ESPE) and nanohybrid universal composite - Tetric EvoCeram (IvoclarVivadent). Release of fluoride ions [µg/mm2 /h] from Tetric EvoCeram and Vitremer into nine environments (artificial saliva - AS, deionized water and 0.9% NaCl) differing in composition of the solution and pH was determined. Six samples were prepared for each solution. In the short-term study, the measurements were taken after 1, 3, 24, 48, 72 and 168 hours...

PURPOSE: This study aimed to develop an energy-absorbing structure for bicycle helmets to minimize head injuries caused by collisions. The research team explored three geometric structures produced through additive methods and compares their energy absorption properties with a standard bicycle helmet made of Expanded Polystyrene (EPS) foam. METHODS: The study prepared samples of three geometric structures (a ball, a honeycomb and a conical shape) and a fragment of a bicycle helmet made of EPS foam with the same overall dimensions...

PURPOSE: The authors of the current study aimed to propose a calibration method for accurate augmented reality visualisation using an optical see-through head-mounted display, and to qualitatively evaluate visualisation accuracy for the application in computer assisted surgery. METHODS: An adaptation of stereo single-point active alignment method was proposed as the calibration procedure together with verification. Three tests were performed: display of points in 3D space, on the plane and on the surface of a skull phantom on inexperience users (5 participants) and experienced users (17 participants)...

PURPOSE: Morphological differences between the two primary great toe flexors - flexor hallucis longus (FHL) and flexor hallucis brevis (FHB) - likely drive differences in how these muscles contribute to functional toe flexor torque production. The aim of the study was to investigate FHL and FHB activation in two isometric toe flexion tasks - one called a "toe-pushing" task with the metatarsophalangeal (MTP) joints dorsiflexed and the interphalangeal (IP) joints in neutral and another called a "toe-gripping" task with the MTP joints in neutral and flexed IP joints...

PURPOSE: Physical activity (PA) is a well-known, simple and effective preventive and therapeutic intervention for low back pain (LBP). In spite of the growing interest in active lifestyles and its benefits, more needs to be known about the relationship between energy expenditure, body mass and lumbar-pelvic kinematics during the forward bending movement in a group of young asymptomatic people who met PA guidelines. Young people can be identified as a future risk group of civilisation diseases and lumbar-hip kinematics can be considered as a predictor of LBP occurrence...

PURPOSE: The aim of this work was to i nvestigate the effects of midsole thickness on non-rearfoot strike runners' redistributions of knee and ankle joint negative and positive work. METHODS: Fourteen healthy male runners wore minimalist, traditional and maximalist shoes and ran in a straight line in each shoe in the laboratory at a speed of 15 km/h, with a ±5% difference being allowed. Whole-body kinematics and ground reaction forces were recorded, and the data of eleven non-rearfoot strikers were used for the analysis...

PURPOSE: This study aimed to examine the effects of age on vertical jump height and handgrip strength measurements in women. A secondary aim was to investigate the correlations between vertical jump height and handgrip strength. METHODS: Twenty young (21.5 ± 2.8 years) and twenty older (67.0 ± 5.5 years) healthy women participated in this study. Handgrip contractions were used to assess strength measurements of peak force and rate of force development at different time intervals...

PURPOSE: Children with cerebral palsy have limitations in utilizing neural information to perform smooth movement and maintain balance during walking. This study aimed to develop a wearable sensor that tracks balance continuously and provides haptic biofeedback to its user through real-time vibration stimulus to assist patients with balance and postural control impairments such as cerebral palsy. METHODS: Twelve children with cerebral palsy and 12 age-matched typically developed children used the sensor during walking at a self- -selected speed...

PURPOSE: The aim of the study was to assess static postural stability under fatigue in subjects with chronic ankle instability - "copers" in comparison with healthy controls. METHODS: We conducted a prospective study on a group of 60 young, physically active subjects, divided into 3 groups: I - 14 subjects with unilateral ankle instability, II - 15 subjects with bilateral ankle instability, III - 31 healthy subjects, without ankle instability. The fatigue trial was based on modified Short-Term Fatigue Protocol...

PURPOSE: Rowing engages large muscle groups and electromyography (EMG) analysis is used to assess athletes' condition and refine sports technique. The aim of the experiment was to evaluate the muscle activation level during different phases of the rowing cycle on an ergometer. METHODS: In a study involving one professional and five amateurs, the mean EMG amplitudes from the quadriceps, gastrocnemius, biceps and triceps brachii were analyzed during different phases of rowing...

PURPOSE: The study aimed to analyze the tarsus and knee setting in 3-year-old girls and boys, taking into account the six-month age ranges. METHODS: The study involved 800 children (400 girls, 400 boys) recruited from randomly selected preschools in the in the Podkarpackie voivodeship. Study group was divided into two age ranges: 1st group (children aged 3.00-3.49 years) and 2nd group (children aged 3.50-3.99 years). Baseline goniometer (Fei Fabrication, Ltd., USA) was used as primary research tool...

PURPOSE: The aim of this paper was the application of a new dynamic-passive method of treatment in correction of hallux valgus and coexisting static deformities of the foot (transverse-plane and plano-valgus foot). METHODS: The study involved 50 patients; 26 with full big toe correction after the passive correction grip (group I) and 24 with big toe correction requiring additional passive abduction (group II). The patients regularly performed exercises using the designed device according to the planned schedule...

PURPOSE: The research was focused on determining basic mechanical properties, surface, and phase structure taking into consideration basic cytotoxicity analysis towards human cells. METHODS: Biological tests were performed on human C-12302 fibroblasts cells using 3D-printed Ti6Al4V alloy (Ti64), produced by laser-based powder bed fusion (LB-PBF) and Alumina Toughened Zirconia 20 (ATZ20), produced by lithography-based ceramic manufacturing (LCM). Surface modifications included electropolishing and hydroxyapatite or hydroxyapatite/zinc coating...

Snoring is common in overweight and elderly patients treated by endovascular stenting. Studies have proved a correlation between snoring and carotid stenosis, thus, snoring after carotid artery stenting (CAS) might promote or worsen clinical performance. This study tested this hypothesis by constructing a patient-specific carotid bifurcation model and numerically analyzing hemodynamic changes of the carotid artery under different snoring conditions. These conditions included small and large amplitude, low and high frequency, and different age groups...

PURPOSE: The aim of this experimental study was to compare the ability of polyurethane cushions of three arbitrary selected thicknesses to minimize vibrations transmitted from the wheelchair to its user. METHODS: Measurements were made during passive motion on five different surfaces often found in public spaces. Two tests were carried out during the measurements. In the first test, the sensor was located directly on the surface of the wheelchair seat. In the second test, a polyurethane cushion was placed on the seat, on which the measuring sensor was then placed...

PURPOSE: Cutting maneuvers are important actions in multidirectional sports but associated with noncontact anterior cruciate ligament (ACL) injuries. This study aimed to investigate the effect of different foot strike patterns and cutting angles on knee kinematics and kinetics. METHODS: Twenty healthy male team sports athletes performed cuts with maximum speed at three angles (45, 90 and 135°) with different foot strike patterns (rearfoot strike [RFS] and forefoot strike [FFS])...

PURPOSE: The aim of the study was to analyze the length and width of the feet and the mutual rate of growth of these features in 3-year-old girls and boys classified into age categories taking into account the semi-annual division. METHODS: The study covered 800 children (400 girls and 400 boys) aged 3. The CQ-ST podoscope was applied as the research tool. The data were analyzed based on Student's t-test for independent samples, Mann-Whitney U-test, Wilcoxon test and simple regression...

A high in-stent restenosis rate and thrombosis have compromised clinical benefits after vascular stent placement. Exercise rehabilitation after stenting emerges as a promising and practical therapeutic strategy to improve the clinical performance of this therapy, although it remains controversial. The present study aimed to explore the impact of exercise training on hemodynamic performance after vascular stent implantation. Different 3-dimensional computational models based on the patient-specific carotids were constructed to calculate hemodynamic parameters, including flow velocity, time-averaged wall shear (TAWSS), oscillatory shear index (OSI) and relative residence time (RRT)...

PURPOSE: The aim of this study was to compare the effect of vision (i.e., open and closed eyes) on the kinetic and kinematic parameters of the standing back tuck somersault (SBTS) in artistic gymnasts and parkour athletes. METHODS: Eleven male parkour athletes (age 22.53 ± 2.36 years; height 1.72 ± 0.08 m; weight 69.58 ± 3.72 kg) and seven male artistic gymnasts (age 21.96 ± 2.64 years; height 1.62 ± 0.02 m; weight 63.54 ± 1.35 kg) participated in this study...

This study was aimed at investigating the joint regulations and body sway after general muscle fatigue during tasks that involve both static and dynamic balance. This cross-sectional study used motion analysis to ascertain the kinematic changes in twelve healthy young individuals before and after running-induced fatigue. Six linear and nonlinear stability metrics were calculated to assess the whole body and joint-related variations. Significant instabilities were observed in the hip and specifically in the knee mechanisms and the whole body during the static condition...