Search Results (181)

Background: The Identification of Functional Ankle Instability (IdFAI) questionnaire is widely used to screen for functional ankle instability (FAI), but its link to objective landing kinetics in multidirectional sports like netball is not well-understood. This study aimed to (i) compare landing kinetics between idFAI stratified netball players, and (ii) examine associations between IdFAI scores with dynamic postural stability (DPS) indices and peak vertical ground reaction forces (PvGRF) during vertical drop landings. Methods: A cross-sectional exploratory study using a repeated-measures landing protocol was conducted on female university netball players (n = 24), stratified into FAI (n = 12) and non-FAI (n = 12) groups using the IdFAI (≥11 indicating possible FAI). Participants completed 18 unilateral drop jump landings in forward (FW), diagonal (DI), and lateral (LA) directions. Ground reaction forces (GRFs) were recorded to obtain DPS and PvGRF metrics (1000 Hz). Mann–Whitney U tests compared FAI groups, and Spearman correlations assessed associations (p < 0.05). Results: Players with FAI showed greater anteroposterior instability during LA landings (U = 33.5, p = 0.020, ES = 0.65). IdFAI scores correlated moderately with lateral anteroposterior deficits (rs = 0.473, p = 0.020, CI = 0.062–0.746). Conclusions: These findings suggest that players with greater FAI display increased anteroposterior instability during LA landings, with higher IdFAI scores moderately associated with these deficits. Despite the small exploratory, hypothesis-generating sample, the results emphasize the practical relevance of direction-targeted landing-stability training to improve DPS in vertical landings. This may provide insight into ankle-injury risk among FAI netball players, given that LA landings represent a documented ankle sprain mechanism. Full article

Background/Objectives: Pes planus is characterized by loss of medial longitudinal foot arch, resulting potentially in dysfunction in balance. Chronic ankle instability (CAI) is related to sensorimotor control deficits. Both of these two musculoskeletal disorders have a diminishing effect on joint proprioception. The present study examined the impact of flatfoot on balance in individuals with CAI. Methods: A total of 28 students (15 men, 13 women; 18–23 years, M = 20.46, SD = 1.07) were assigned to CAI with pes planus (n = 15) or CAI only (n = 13). Balance was assessed using the Y-balance test (YBT) and modified star excursion balance test (mSEBT) in three directions (anterior, posteromedial, and posterolateral), alongside the Cumberland ankle instability tool (CAIT). Group differences were analyzed with independent t tests or Mann–Whitney U tests (α = 0.05). Results: The findings of the study did not show statistically significant differences between the two groups in the balance variable [mSEBT/anterior left foot (t = 0.239, p = 0.865); mSEBT/posteromedial left foot (t = −0.048, p = 0.562); mSEBT/posterolateral left foot (t = 0.164, p = 0.258); mSEBT/anterior right foot (t = −0.433, p = 0.748); mSEBT/posteromedial right foot (t = 0.745, p = 0.606); mSEBT/posterolateral right foot (t = 0.263, p = 0.680); YBT/anterior left foot (U = 96.00, p = 0.93); YBT/posteromedial left foot (U = 94.50, p = 0.87); YBT/posterolateral left foot (U = 96.00, p = 0.93); YBT/anterior right foot (U = 95.50, p = 0.92); YBT/posterolateral right foot (U = 82.50, p = 0.45)]. However, a trend towards significance was found as patients with flatfeet had a weaker performance in balance tests [posteromedial direction of the YBT for the right foot (U = 70.00, p = 0.12)]. Conclusions: Although pes planus did not seem to affect the balance ability of individuals with CAI, future studies should confirm the relationship of pes planus and CAI with a larger group, including variables such as ankle range of motion, muscle strength, and functional activity level. A better understanding of the above relationship may lead to more precise diagnostic processes and more efficient therapies in CAI. Full article

Background: Ankle sprains affect approximately 8% of the general population, and recurrence occurs in as many as 80% of patients participating in high-risk sports. The aim of this review was to assess the impact of physiotherapy interventions on chronic ankle stability (CAI), providing evidence for the effectiveness of clinical treatment and care for patients with CAI. Methods: A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Randomized controlled trials (RCTs) evaluating the effectiveness of physiotherapy interventions in athletes with CAI following injury were analyzed. PubMed, Embase, PEDro, and Cochrane electronic databases were searched. A modified McMaster Critical Review Form for quantitative studies was used to assess the methodological quality of the included studies, in accordance with the guidelines. Results: The literature search yielded 316 results, of which 13 articles met all required eligibility criteria and were included in the study. The RCTs included 490 athletes with CAI. Interventions included various types of exercises, including balance training (BT), plyometric training, CrossFit, and neuromuscular training. The duration of the intervention was 4–12 weeks. Both subjective and objective measures were used to assess the effectiveness of the therapy in the following seven domains: Dynamic Balance, Static Balance, Patient-Reported Outcomes, Kinematic Outcomes, Proprioception, Body-Composition, and Strength Assessment. Conclusions: The evidence supports the effectiveness of rehabilitation interventions in athletes with CAI. Further large-scale randomized controlled trials, incorporating control groups and long-term follow-up, are needed to better determine the robust impact of conservative management on improving both the physical and psychological health of patients with CAI. Full article

(1) Background: Ankle joint range of motion is recognized as abnormal in individuals with ankle sprains and Chronic ankle instability (CAI), especially in the dorsiflexion movement. This research investigated the test–retest and inter-rater reliability of the Motustech Beyond IMU for dorsiflexion movement following only one hour of rater training and familiarization. (2) Methods: In total, 62 subjects were evaluated for the inter-rater reliability and test–retest with a one-week interval. The intraclass correlation coefficient (ICC), along with the Concordance Correlation Coefficient (CCC), was determined for each test of reliability. Standard error of measurement, coefficients of variation, limits of agreement (LoA) and minimal detectable change (MDC) were used for the measurement error analysis. (3) Results: Test–retest reliability was ranked excellent (ICC = 0.949) and very high (CCC = 0.897) for both ankle dorsiflexion measurements. On the other hand, Inter-Rater reliability was evaluated as good (ICC = 0.881–0.906) and very high (CCC = 0.783–0.811). However, the measurement error analysis showed poor absolute agreement (LoA), indicating that the resulting measurement variability is considered clinically unacceptable for high-precision applications. (4) Conclusions: Beyond Inertial demonstrated excellent test–retest reliability for ankle dorsiflexion movements, although measurement error analysis showed considerable absolute error. Consequently, it may be considered a reliable tool for single-rater monitoring of ankle dorsiflexion ROM in non-clinical settings such as general physical activity and amateur sports. Future research should investigate its potential role in injury prevention contexts. Full article

Generalised joint hypermobility (GJH) describes an excessive range of joint movement and is associated with increased musculoskeletal injury risk, joint pain, and instability. This study compares lower limb biomechanical characteristics between children with and without GJH. Children aged 5–18 years with GJH (Beighton score ≥ 6/9 pre-puberty, ≥5/9 post-puberty) were age- and sex-matched with controls (Beighton score ≤ 2/9). Biomechanical measures included internal hip rotation, quadriceps (Q) angle, tibial torsion, ankle range of motion (ROM), and foot posture index (FPI). Wilcoxon rank sum test and chi-square were used to assess group differences. Fifty-two participants (median age 11 years, 69% females) included 27 children with GJH and 25 healthy children. Internal hip rotation, Q-angle, ankle ROM and FPI were significantly higher for children with GJH (p < 0.001) than healthy peers. While tibial torsion showed no difference in males, females had greater internal tibial torsion [median difference: right −4° (95%CI:−7,−2), p = 0.002; left −5° (95%CI:−7,−1), p = 0.010]. The largest differences were in ankle ROM [median difference: right 9° (95%CI:7,12); left 9° (95%CI:6,12)]. Children with GJH present different biomechanical measures than non-GJH peers. Further research into the clinical relevance of ROM at the hip, ankle and foot for children with GJH which are movement planes not assessed in Beighton score is warranted. Full article

Osteochondral lesions of the talus (OLTs) present a significant clinical challenge, often leading to pain, dysfunction, and joint degeneration. Traditional treatments, including microfracture and grafting, have limitations in their ability to fully restore osteochondral integrity. Recent advances in tissue engineering have introduced heparin-conjugated fibrin hydrogel (HCFH) as a promising scaffold for regenerative therapy. By supporting mesenchymal stem cell (MSC) proliferation and controlled growth factor release, HCFH enhances cartilage and bone repair. A 21-year-old female presented with chronic right ankle pain and instability following a sports injury, with MRI revealing an osteochondral lesion in the lateral dome of the talus and an anterior talofibular ligament injury. Treatment included autologous MSC isolation, HCFH synthesis, arthroscopic debridement, microfracture, and implantation of MSC-loaded HCFH, while postoperative rehabilitation involved four weeks of restricted weight-bearing- and physiotherapy. At 12 months, her visual analog scale (VAS) score decreased from 60 to 40, indicating clinical improvement, and her American Orthopaedic Foot and Ankle Society (AOFAS) score increased from 69 to 77. Serial MRI scans showed progressive cartilage regeneration with near-complete defect filling. This case highlights the potential of MSC-loaded HCFH in treating OLTs. The observed improvements in pain relief, function, and cartilage regeneration suggest that this technique may overcome the limitations of conventional treatments. Further studies with larger cohorts and long-term follow-up are necessary to confirm its clinical efficacy. Full article

To compare lower limb joint angle variability between functional ankle instability (FAI) and healthy controls (CONs) at different running speeds using linear and nonlinear methods. Fifteen males with right-side FAI and fifteen matched CONs ran on a treadmill at self-selected, 20% faster, and 20% slower speeds. From 25 gait cycles, the mean coefficient of variation (CV), Sample Entropy (SampEn), and largest Lyapunov Exponent (LyE) of hip, knee, and ankle angles were computed. A two-way (two groups × three speeds) mixed-design ANOVA was applied (α = 0.05). No significant interaction effects were observed. No significant differences were observed in the CV. SampEn showed group effects: FAI had lower values in hip horizontal, knee sagittal/coronal, and ankle coronal planes, but higher in the hip sagittal plane. Speed effects showed greater SampEn in the ankle sagittal and lower in the hip coronal plane at slow speed. LyE was reduced in FAI for hip, knee, and ankle sagittal planes. Speed effects indicated higher LyE in the knee sagittal and lower in the hip coronal plane at slow speed. FAI showed reduced variability, particularly in the sagittal plane, reflecting rigid control. Slower speeds increased ankle and knee sagittal variability but decreased hip coronal variability. Full article

(1) Background: Chronic ankle instability (CAI), a common outcome of ankle sprains, involves recurrent sprains, balance deficits, and gait impairments linked to both peripheral and central neuromuscular dysfunction. Dual-task (DT) demands further aggravate postural control, especially during stair descent, a major source of fall-related injuries. Yet the biomechanical mechanisms of stair-to-ground transition in CAI under dual-task conditions remain poorly understood. (2) Methods: Sixty individuals with CAI and age- and sex-matched controls performed stair-to-ground transitions under single- and dual-task conditions. Spatiotemporal gait parameters, center of pressure (COP) metrics, ankle inversion angle, and relative joint work contributions (Ankle%, Knee%, Hip%) were obtained using 3D motion capture, a force plate, and musculoskeletal modeling. Correlation and regression analyses assessed the relationships between ankle contributions, postural stability, and proximal joint compensations. (3) Results: Compared with the controls, the CAI group demonstrated marked control deficits during the single task (ST), characterized by reduced gait speed, increased step width, elevated mediolateral COP root mean square (COP-ml RMS), and abnormal ankle inversion and joint kinematics; these impairments were exacerbated under DT conditions. Individuals with CAI exhibited a significantly reduced ankle plantarflexion moment and energy contribution (Ankle%), accompanied by compensatory increases in knee and hip contributions. Regression analyses indicated that Ankle% significantly predicted COP-ml RMS and gait speed (GS), highlighting the pivotal role of ankle function in maintaining dynamic stability. Furthermore, CAI participants adopted a “posture-first” strategy under DT, with concurrent deterioration in gait and cognitive performance, reflecting strong reliance on attentional resources. (4) Conclusions: CAI involves global control deficits, including distal insufficiency, proximal compensation, and an inefficient energy distribution, which intensify under dual-task conditions. As the ankle is central to lower-limb kinetics, its dysfunction induces widespread instability. Rehabilitation should therefore target coordinated lower-limb training and progressive dual-task integration to improve motor control and dynamic stability. Full article

Knee osteoarthritis (OA) is a prevalent condition in older adults that often results in impaired gait and balance, increased risk of falls, and reduced quality of life. Conventional clinical assessments may not adequately capture these deficiencies. This study investigated the gait and balance of elderly individuals with knee OA using wearable inertial measurement units (IMUs). Forty-four participants with Kellgren–Lawrence grade 2–3 knee OA (71.23 ± 5.75 years) and forty-five age-matched controls (70.87 ± 4.30 years) completed dynamic balance (balance board), static balance (single-leg stance), ‘timed up and go’ (TUG), and normal walking tasks. Between 2 and 8 IMUs, depending on the task, were placed on the head, chest, waist, knees, ankles, soles, and balance board to record kinematic data. Balance was quantified using absolute angular velocity and linear acceleration, with group differences analyzed by MANOVA and Bonferroni-adjusted univariate tests. The participants with knee OA exhibited greater gait asymmetry, although the difference was not significant. However, they consistently demonstrated higher absolute angular velocities than controls across most body segments during static and dynamic tasks, indicating reduced postural stability. No group differences were observed in TUG performance. These findings suggest that IMU-based measures, particularly angular velocity, are sensitive to balance impairment detection in knee OA. Incorporating IMU technology into clinical assessments may facilitate early identification of instability and guide targeted interventions to reduce fall risk. Full article

Background/Objectives: Chronic ankle instability is a common issue after lateral ankle sprain. The DMA Clinical Pilates method hypothesizes impairments in tibialis anterior and fibularis longus muscles. Methods: A total of 14 adults with chronic ankle instability, and 15 recovered and 16 healthy individuals were prospectively recruited and assessed for lower back, hip, knee, and ankle muscle activities during dominant and non-dominant sides single-leg stand on stable and unstable surfaces using wireless surface electromyography. Results: The study found consistent dysfunction in tibialis anterior muscle activity in adults with chronic ankle instability when compared with healthy adults during single-leg stand on stable and unstable surfaces, and against recovered individuals on unstable surface. As compared to healthy controls, chronic ankle instability group showed higher vastus lateralis activation during dominant side single-leg stand across surface conditions and during dominant side single-leg stand, while the higher dominant side longissimus dorsi activity on stable surface changed to higher dominant side medial gastrocnemius activity on unstable surface. As compared to recovered controls, chronic ankle instability group also showed higher gluteus medius and fibularis longus muscle activities on unstable surface. Conclusions: Tibialis anterior muscle is the main dysfunction among individuals with chronic ankle instability side. Full article

Background: Functional performance interlimb asymmetry may increase the risk of ankle sprains during basic military training. We aimed to (1) evaluate interlimb balance, agility, and ankle instability asymmetry in soldiers in infantry training as a risk factor for acute ankle sprains; (2) evaluate the effect of ankle sprains and sprain prevention exercise program on performance asymmetry. Methods: Newly inducted infantry soldiers were recruited from two induction cycles (intervention [INT] n = 365, control [CON] n = 421). Participants were assessed at the beginning of infantry basic training (T0) and after four months (T1) for anthropometrics, balance, agility, and perceived ankle instability, and were monitored for ankle sprains (SPRAIN/NO-SPRAIN). The INT group performed an ankle sprain prevention program 5 days/week × 5 min/day. Results: at T0 there were differences in interlimb asymmetry in Cumberland Ankle Instability Tool (CAIT) in SPRAIN soldiers in both groups (p-value < 0.001), and differences between the groups in Hexagon, Y-Balance Test (YBT) and CAIT (p-values 0.007, 0.002, 0.002, respectively). There was a decrease in interlimb asymmetry in Hexagon and YBT for SPRAIN soldiers in the INT group, and an increase in CAIT asymmetry in SPRAIN soldiers in both groups. Stepwise logistic regression did not find predictors for ankle sprains during training. Conclusions: The intervention program reduced interlimb asymmetry in balance and agility for soldiers who sprained their ankle during training. In these soldiers, CAIT asymmetry increased during training regardless of the intervention. Ankle sprain intervention programs should be implemented to reduce interlimb asymmetries in functional abilities and reduce the risk of injury. Full article

This study proposes a methodology for conducting computational simulations of pathological gait. The literature shows a consensus that biomechanical models for gait analysis should be formulated as control problems. To achieve this, it is common practice to guide the solution using kinematic or kinetic data to prevent temporal instability. The aim of this study is to implement a biomechanical model of the Charcot–Marie–Tooth disease in OpenSim software that enables more comprehensive simulations, which may in future involve the musculoskeletal system of patient and predictive studies. In this way, it will be possible to design specific active assistive devices tailored to each patient. Experimental gait data from six Charcot–Marie–Tooth patients were used. The dataset comprises three-dimensional trajectories of reflective markers placed according to the Davis-Heel protocol. The acquired data allowed a patient-specific adjustment of the biomechanical model. The inverse kinematic was solved, and the results were validated by comparing them with those obtained using the commercial BTS Bioengineering^® software. The results show a strong alignment in ankle kinematics between the OpenSim model and the data generated by BTS Bioengineering^®. Additionally, the kinematic results have been compared with normative curves, allowing the identification of potential areas for intervention using active assistive devices aimed at improving movement patterns of patients. Full article

This study used stair-embedded force plates to investigate the effects of lower-limb muscle fatigue on dynamic postural control during stair descent in young adults. Twenty-five healthy male adults (age = 19.2 ± 1.5 years) were tested for stair descent gait in pre-fatigue and post-fatigue conditions. To induce fatigue, participants performed a sit-to-stand task. The kinematic and kinetic data were collected synchronously, and gait parameters were analyzed. Data were analyzed using one-dimensional statistical parametric mapping (SPM1d) and paired t-tests in SPSS. After fatigue, the right knee flexion angle increased significantly across all phases (0–14%, p < 0.001; 14–19%, p = 0.032; 42–50%, p = 0.023; 60–65%, p = 0.022; 80–100%, p = 0.012). Additionally, the step width widened notably (p < 0.001), while the proportion of the swing phase decreased (p = 0.030). During the event of right-foot release, the left knee flexion (p = 0.005) and ankle dorsiflexion (p = 0.001) angle increased significantly, along with a larger left ankle plantarflexion moment (p = 0.032). After fatigue, the margin of stability in the anterior–posterior direction (MoS-AP) (p = 0.002, p = 0.014) and required coefficient of friction (RCOF) (p = 0.031, p = 0.021) significantly increased at the left-foot release and right-foot release moments. This study demonstrates that lower-limb muscle fatigue increases dynamic instability during stair descent. Participants adopted compensatory strategies, including widening step width, reducing single-support duration, and enhancing ankle plantarflexion to offset knee strength deficits. These adaptations likely reflect central nervous system mechanisms prioritizing stability, highlighting the ankle’s compensatory role as a potential target for joint-specific interventions in fall prevention and rehabilitation. Future studies should investigate diverse populations, varying fatigue levels, and comprehensive neuromuscular indicators. Full article

Background and Clinical Significance: Posteriorly migrated lumbar disc herniation [PMLDH] is a rare entity that may present with atypical clinical and radiological features, often mimicking other spinal pathologies. Migration of sequestered fragments through the interlaminar space is exceptionally uncommon, and diagnostic challenges are further amplified in the presence of spinal instability. While MRI and CT are generally sufficient for diagnosis, undetected lesions on preoperative imaging may complicate clinical management. Case Presentation: A 59-year-old male presented with acute low back pain and left-sided radiculopathy. Examination revealed mild motor weakness in ankle dorsiflexion. MRI showed L4–L5 segmental instability with central canal stenosis but no migrated disc fragment. Owing to neurological deficit, decompressive laminectomy with posterior instrumentation was performed. Intraoperatively, a posteriorly migrated sequestered fragment compressing the thecal sac was excised and confirmed as degenerative disc material. Postoperatively, the patient’s neurological deficit and radicular pain resolved, with no new complaints at 3-month follow-up. Conclusions: This case highlights an unusual presentation of PMLDH in a patient with lumbar stenosis and spinal instability, undetected on preoperative imaging. Recognition of the biomechanical predisposition at the L3–4 and L4–5 levels is important in understanding such rare migrations. Although literature emphasizes early surgical intervention for PMLDH, our patient required urgent surgery due to neurological deficits rather than a definitive preoperative diagnosis. Further studies are warranted to clarify the relationship between instability and posterior migration. Full article

Background and Objectives: Chronic ankle instability (CAI), a prevalent injury among female volleyball players, can negatively affect functional performance and increase the risk of further injury. The aim of this study was to compare functional movement quality, dynamic balance, vertical jumping performance, hip muscle strength, and risk of injury between adolescent female volleyball players with unilateral CAI and those without CAI. Materials and Methods: This cross-sectional study included 46 adolescent female volleyball players, divided into CAI (n = 23) and control (n = 23) groups based on predefined criteria. Functional movement quality was assessed using the Functional Movement Screen (FMS), and dynamic balance was evaluated with the Y-Balance Test (YBT). Maximal isometric strength of the hip muscles (flexors, extensors, abductors, adductors, and internal and external rotators) was measured using hand-held dynamometry, and vertical jumping performance was assessed using countermovement jump tests. Injury risk was classified based on established cut-off values for the FMS-composite and YBT-anterior reach asymmetry scores. Results: The CAI group demonstrated significantly lower FMS-composite scores (p = 0.007), reduced anterior reach on the YBT (p = 0.004), and decreased strength in the hip flexors (p = 0.007) and hip adductors (p = 0.044), supported by moderate effect sizes. No significant group differences were observed in the other YBT directions, vertical jump tests, or the other hip muscles (p > 0.05). A greater proportion of athletes in the CAI group were classified as high risk for injury based on both FMS-composite (p = 0.022) and YBT-anterior reach asymmetry (p = 0.001) cut-off values, supported by moderate and relatively strong effect sizes, respectively. Conclusions: Adolescent female volleyball players with unilateral CAI showed impaired movement quality, balance deficits, hip muscle weakness, and increased injury risk. These results highlight the importance of targeted interventions and broader investigations into CAI in adolescent athletes. Full article