Acta of bioengineering and biomechanics最新文献

Purpose: Abnormalities in bone structure impact motor functions, including the ability to maintain stable posture. This study assessed static and dynamic balance in patients with osteogenesis imperfecta (OI) across different disease types, compared to a healthy population. Methods: The study group included 87 patients with OI: Type I (n = 45), Type III (n = 28), and Type IV (n = 14). Balance was assessed using the AMTI (Advanced Mechanical Technology, Inc.) platform. Measurements in standing (ST) position during anterior-posterior (AP) and medial-lateral (ML) tilts, with eyes open, for 30 seconds. Results: Significant differences in balance parameters under static conditions were found between OI types (61.5% between Types I and III, 38.5% between Types I and IV, and 30.7% between Types III and IV). Across all OI types, maintaining balance predominantly involved displacement of the COP (Centre of Pressure) in the sagittal plane, observed in 84.7% of Type II OI, 75.2% of Type III OI and 74.5% of Type IV OI cases. Under dynamic conditions, significant differences in balance parameters were noted in 84.6% of comparisons between Types I and III, 46.1% between Types I and IV, and 69.2% between Types III and IV. Conclusions: Balance assessment in individuals with OI is essential for injury prevention, improving mobility and daily function, and monitoring therapy effectiveness. Development of more preventive strategies aimed at reducing fracture risk and enhancing the quality of life for these patients. The relatively small number of patients with type III and the wide age range represent limitations of our study.

Purpose: The determinants of the sports results of young and adult swimmers differ, especially in sprint races (50-100 m). Their identification can be used to assess the athlete's potential and to set appropriate requirements. The aim was to distinguish energy-anthropometric profiles (clusters) among young athletes and to characterize their kinematic indices in freestyle sprint races (50-100 m). Kinematic variables from both distances were compared in each cluster. Methods: Anthropometric indices and mechanical power of the upper limbs (arm-cranking) were determined in 43 subjects (boys, aged 12-13 years), which were used for cluster analysis. For the 50- and 100-m races the following were determined: velocity (v), stroke rate (SR), stroke length (SL) and stroke index (SI). Comparative analysis was performed between clusters and between distances. Results: The following clusters were distinguished: Large (LSP), Medium (MSP) and Small Size and Power (SSP), which differed due to anthropometric and power indices. Intergroup differences (LSP, MSP and SSP, respectively) were revealed in v ₅₀ (1.65, 1.55, 1.49 m/s), v ₁₀₀ (1.52, 1.41, 1.34 m/s), SL₁₀₀ (1.92, 1.77, 1.72 m), SI₅₀ (2.92, 2.65, 2.54 m/s²), SI₁₀₀ (2.91, 2.51, 2.31 m/s²). In all clusters differences were revealed between v ₅₀ and v ₁₀₀ and SR₅₀ and SR₁₀₀. Differences in SL₅₀ and SL₁₀₀ were noticed in LSP and MSP, while in SI₅₀ and SI₁₀₀ in MSP and SSP. Conclusions: The evaluation of the technique should consider the energy-anthropometric profile of the athlete. The swimming technique need to be modified depending on the distance - also in races perceived as sprints.

Purpose: The aim of this study was to investigate the feasibility of using Long Short-Term Memory (LSTM) neural networks to predict Taekwondo kick force from data obtained by inertial measurement unit (IMU) sensors, providing a cost-effective alternative to traditional force plates in sports biomechanics. Methods: IMU (Noraxon Ultium) data from 13 International Taekwon-do Federation (ITF) athletes (9 training, 4 validation) across genders and skill levels (expert in training, expert/advanced in validation) were collected. Sensors were attached to a foot, shank and tight of kicking leg. Athletes performed turning kicks in diverse stances towards a padded force plate (2000 Hz) attached to a wall. LSTM models were trained to predict kick force value, and trained on capturing the IMU data from sensors placed on the lower limb. Results: The trained LSTM models showed accuracy on the training data (R ² values in the range of 0.972-0.978). Feature validity analysis highlighted the importance of ankle dorsiflexion in shaping the model score. Model performance on the validation dataset was less consistent, ranging from good accuracy (RMSE 6.91) to poor accuracy (RMSE over 30), depending on the participant tested. Conclusions: This study demonstrated the potential of LSTM models combined with IMU data to predict Taekwondo kick forces. Although the validation performance indicated the need for further model refinement or the inclusion of additional input variables, the results highlighted the feasibility of predicting force values without relying on a force plate. This approach could enhance the accessibility of field studies conducted outside laboratory settings.

The endovascular stent implantation is a significant and efficacious cardiovascular interventional treatment. However, the underlying mechanisms behind in-stent neoarteriosclerosis and restenosis following the intervention remain unclear. Our hypothesis posits that stent implantation may impact the transportation of low-density lipoproteins (LDL) within the host artery, thereby disrupting its concentration distribution and leading to adverse clinical events. To validate this hypothesis, we conducted a numerical investigation to examine the influence of stenting on LDL distribution, utilizing a lumen-wall model based on the coronary artery. The findings of the study suggest that the introduction of an implanted stent can disrupt blood flow and result in an abnormal accumulation of lipids on the inner surface of the arterial wall, particularly in the vicinity of the strut protrusion. Additionally, improper stent implantation, characterized by thick struts, reduced spacing between struts, and non-streamlined struts can exacerbate the local mechanical conditions of the host artery and contribute to a relatively high concentration of low-density lipoprotein (LDL) near the stent strut. In summary, the presence of a stent in the artery leads to an elevated LDL concentration both within the stented segment and downstream, potentially leading to adverse consequences.

Purpose: Last years brought a growing interest in suture-tape augmented ACL repair techniques instead of ACL reconstructions with autografts due to their limited success rates. However, there is a lack of experimental studies comparing the infl uence of both procedures on knee periarticular muscles biomechanics. The aim of the study was to analyze periarticular muscles torq ue and their activity during movement for young patients after ACL repair (IB) and ACL reconstruction (ACLR), compare them with each other and with a healthy subjects (Controls). Methods: Isokinetic torques of knee flexors and extensors and their EMG activity during gait and drop vertical jump (DVJ) were measured in 48 patients (IB - 20, ACLR - 28) at least one year after surgery and in 25 healthy controls. Results: The muscle torques in the operated limb were lower in both group of patients comparing to Controls, but IB scored the lowest values (79% of Controls for extensors, p = 0.005; 74% for flexors, p = 0.001). Decrease of muscle torques in the contralateral limb occurred only in IB group (84% of Controls for both extensors ( p = 0.045) and flexors). Increased hamstrings activity were noticed for ACLR comparing to IB and Controls. The balance between activity of muscles actin g on the medial and lateral side of the knee for ACLR tilts more towards the lateral side. Conclusions: Increased hamstrings activity and changes in balance between laterally and medially located muscles indicate on the increased need for muscle support of kn ee stability in ACLR patients.

Purpose: This study investigated whether kinesiotaping applied to the ankle joint after exercise causing fatigue of the muscles stabilising this joint has an effect on the ability to maintain static balance, dynamic balance and weight-bearing ankle dorsiflexion range of motion in male football players without ankle pain and instability. Methods: The study included 50 men aged 18-30 years, practising football, assigned to the study group (subjected to kinesiotaping for the ankle joint) or the control group (without kinesiotaping). Exam 1st was performed prior to a 20- minute physical exercise causing fatigue of the muscles stabilising the ankle joint. Kinesiotaping was then applied in the study group. Exam 2nd was performed after exercise. Research tools were the Flamingo Balance Test (FBT), the Y-Balance Test (YBT) and Ankle Lunge Test (ALT). The data were analyzed based on Student's t-test for independent variables, Mann-Whitney U-test, Student's t-test for dependent variables, Wilcoxon test. Results: In the case of FBT, the values of the differences in 1st and 2nd examination results did not yield statistically significant results (p > 0.05), and for YBT and ALT, the values for the differences between 1st and 2nd examination in the study group were greater than in the control group (p < 0.05). Conclusions: Kinesiotaping applied to the ankle joint after exercise causing fatigue of the muscles stabilising this joint has a beneficial effect on the ability to maintain dynamic balance and weight-bearing ankle dorsiflexion range of motion, whereas it does not significantly improve static balance in male football players without ankle pain and instability.

Purpose: This study investigates inter-limb asymmetry during drop vertical jumps in elite female football players by examining biomechanical variables, such as joint kinematics and ground reaction forces, that are strongly associated with increased anterior cruciate ligament injury risk. Methods: Kinematic and kinetic parameters of 12 football players performing a vertical drop jump from a 30 cm high box were recorded using the Xsens MVN Awinda motion capture system and Vald Force Decks. Results: The findings revealed significant differences in range of motion between the limbs, particularly in internal/external rotation and dorsiflexion/plantarflexion ( p < 0.05). No significant differences were found in abduction/adduction or flexion-extension ROM between limbs during both landing phases. Internal/external rotation range differed significantly during the first landing phase ( p < 0.05), but not the second. Hip joint flexion/extension exhibited minimal variation compared to the ankle and knee, with slight increases observed at the hip. From a kinetic standpoint, concentric mean power demonstrated a strong positive correlation with peak power ( ρ = 0.903), underscoring its crucial role in optimizing performance and mitigating injury risk. Conclusions: The study evaluated biomechanical indicators strongly linked to ACL injury risk. Findings highlight that asymmetrical loading and movement patterns, especially knee valgus and inter-limb discrepancies, may predispose female athletes to non-contact ACL injuries. These results emphasize the need for neuromuscular training interventions targeting symmetry, proprioception, and controlled landing to reduce injury risk and enhance performance.

Purpose: This study utilized a combination of musculoskeletal modeling and finite element analysis to investigate the effects of varying ankle dorsiflexion ranges on knee joint loading, soft tissue stress distribution, and the coactivation patterns of muscles surrounding the knee during landing. Methods: Based on the Weight-Bearing Lunge Test (WBLT), a total of 32 basketball players into two groups: normal dorsiflexion (ND) and limited dorsiflexion (LD) and conducted six countermovement jumps (CMJ) while collecting motion and force data. Personalized musculoskeletal models were created using OpenSim to analyze kinematics and kinetics, and Helium-free MRI and CT scans were used for finite element modeling to assess internal tissue stress in the knee. Results: During landing, the patellofemoral joint contact force in LD was reduced compared to the ND. The coactivation of muscles around the knee joint decreased. The von Mises stress in the tibial cartilage, meniscus, anterior cruciate ligament and posterior cruciate ligament were elevated. Conclusions: The results suggest that increased ankle dorsiflexion during landing may effectively reduce internal tissue stress in the knee joint while enhancing muscle coactivation around the knee joint and increasing patellofemoral joint contact force. These findings provide valuable theoretical support for strategies to reduce the risk of knee injuries during landing. Additionally, they offer reliable technical approaches and theoretical insights for studying injury mechanisms in other sports activities, such as running and lateral jumping.

Purpose: Multiple sclerosis (MS) is characterised by multifocal and damage disseminated in time to the central nervous system. This causes various clinical symptoms, including spastically increased muscle tone and balance disorders, which already occur in the early stages of the disease, increasing the frequency of falls, which negatively affects the mobility and independence of patients. Whole-body cryotherapy (WBC) is used in the rehabilitation of MS patients, however, there are no reports on the effect of WBC without subsequent kinesiotherapy on body balance in patients with MS. The aim of the study was to assess the effect of a series of 10 and 20 WBC without kinesiotherapy on the degree of disability assessed by the Expanded Disability Status Scale (EDSS), muscle spasticity evaluated using the Modified Ashworth scale (MAS) and body balance in patients with multiple sclerosis. Methods: The study was completed by 51 patients, aged 23 to 65 years, with a disability grade of 3.5-6.5 on the EDSS scale and spasticity 0-3.0 assessed by the MAS. Patients were randomly assigned to the control group (n = 18) or the experimental group participating in 20 WBC sessions (n = 33). Balance assessment consisted of performing two, 30-second static tests on stabilometric platform, the first test with eyes open and the second one with eyes closed. During these tests, the centre of foot pressure displacement was monitored and analysed in real time. Results: A series of 20 daily WBC resulted in an improvement in the functional status of patients with multiple sclerosis in the form of a significant reduction in EDSS values and spasticity, both on the side with greater and less spasticity. Under the effect of whole-body cryotherapy treatments, there was slight improvement in the stability in patients with multiple sclerosis. Conclusions: Based on the obtained results, it can be concluded that WBC, without subsequent targeted kinesiotherapy, are not sufficient to obtain clear and measurable benefits in the rehabilitation of patients with multiple sclerosis.

Purpose: The aim of this study was to assess the change in psychophysical performance of patients after lumbar discectomy in relation to the postoperative rehabilitation programme. Methods: The study involved 60 participants randomly divided into two groups of 30 individuals. Both groups participated in a basic version of the rehabilitation programme, and individuals in the study group additionally received manual therapy. The evaluation was performed twice, before the start and after the completion of the 3-month rehabilitation programme. The tests were carried out to measure static balance, functional status using Oswestry Disability Index (ODI) and Roland-Morris Disability Questionnaire (RMDQ), lumbar spine range of motion using the original Schober's test and the intensity of pain using the Visual Analogue Scale (VAS). Results: Both groups showed significant improvement in most of the psychophysical parameters assessed (study versus control p < 0.01, p < 0.05), except for the parameters of balance. In the study group, significant changes occurred in all parameters except X average, Area circular and average velocity in trials with eyes closed and left leg stance after rehabilitation ( p < 0.05). The findings showed significant differences in the reduced pain intensity on the VAS (p = 0.0001), improved functional status in ODI and improved static balance ( p < 0.01), in favour of the study group. Conclusions: The protocol which additionally included manual therapy was found to be more effective than the basic programme. Its superiority was reflected by greater pain reduction, more visibly improved functional status as well as improved static balance.