SEARCH · Search PubMed

Results for “biomechanics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

20 recordsLinked to original sources

PubMed2026

Barefoot ambulation following partial foot amputation: A systematic review of biomechanical outcomes.

BACKGROUND: Partial foot amputation (PFA) is increasingly performed due to rising prevalence of diabetes and peripheral vascular disease. While PFA may preserve gait and reduce energy expenditure compared with transtibial amputation, biomechanical deficits are common. This review aimed to evaluate biomechanical outcomes during baref following PFA. METHODS: A systematic review was conducted. MEDLINE, Embase, CINAHL, SCOPUS and Web of Science databases were searched for studies reporting biomechanical outcomes in adults with PFA without prosthesis. Eligible outcomes included spatiotemporal metrics, joint kinematics and kinetics, plantar pressures, and ground reaction forces. FINDINGS: Twelve studies including a total of 101 participants met inclusion criteria. Across studies, PFA was associated with impaired barefoot gait. This included spatiotemporal changes, such as reduced walking speed and shorter step length, and kinetic changes, such as reduced ankle power. Elevated plantar pressures were commonly reported, particularly in the forefoot and midfoot, highlighting loading abnormalities in the residuum. Several studies also described proximal compensatory strategies at the knee and hip, suggesting that biomechanical consequences extend beyond the foot and ankle. However, the evidence base was limited by small sample sizes, inconsistent protocols, and substantial heterogeneity. INTERPRETATION: Barefoot walking is impaired after partial foot amputation and the degree of dysfunction may vary by amputation level. Abnormal loading and compensatory changes may extend beyond the foot and ankle to the knee and hip. Given the limited and methodologically heterogeneous evidence, larger prospective studies with standardised biomechanical outcomes are needed to clarify the effects of amputation level and aetiology. This standardisation is important to inform surgical planning, rehabilitation, and prosthetic device design.

Humans↗

PubMed2026

Anatomy and Biomechanics of the Deltoid Ligament Complex in Healthy Ankles: Protocol for a Systematic Review and Meta-Analysis.

INTRODUCTION: Up to one in two individuals who have a history of an ankle injury will develop chronic ankle instability, which subsequently increases the risk of osteoarthritis development. Although lateral ankle ligament injuries are the most common, recent research shows that concomitant injuries to the deltoid (medial collateral) ligament complex may be more prevalent than previously recognised. However, the anatomy and biomechanics of the deltoid ligament complex are reported inconsistently in the literature. This systematic review will summarise current evidence on the anatomy and biomechanics of the deltoid ligament complex in healthy adult ankles. METHODS: Searches will be conducted in Scopus, MEDLINE, Embase, CINAHL and SPORTDiscus. Our search strategy will cover terms associated with 'deltoid ligament', 'anatomy' and 'biomechanics'. We will only include dissection and imaging studies published in English that report any of the listed clinically relevant properties of the deltoid ligament in healthy adult human ankles. Two reviewers will independently perform screening and assess study quality using the anatomical quality assessment (AQUA) tool. One reviewer will extract relevant data, which will be independently verified by co-authors. Primary outcomes include band prevalence, length, width, cross-sectional area, maximum and/or failure load and elastic modulus. If three or more studies report a primary outcome, we will conduct a meta-analysis and report findings as pooled means with 95% confidence intervals. If a meta-analysis is not feasible, outcomes will be summarised as a narrative analysis. Measures will be taken during data synthesis to address anticipated methodological heterogeneity across included studies, and pooled estimates will be interpreted with caution. DISCUSSION: This protocol details a systematic review that aims to summarise the anatomy and biomechanics of the deltoid ligament complex. Our findings will inform computational modelling, clinical management and biomechanics for ankle pathologies, as well as identifying research gaps and directions for future research. TRIAL REGISTRATION: PROSPERO: CRD420251142867.

Humans↗

PubMed2026

All-inside repair is an effective treatment for medial meniscus posterior root tears: a systematic review and meta-analysis of biomechanical and clinical evidence.

BACKGROUND: Medial meniscus posterior root tears (MMPRTs) reproduce the biomechanics of subtotal meniscectomy. Repair is favored, but the role of all-inside repair (AR) remains unclear relative to transtibial pull-out (TP). This study aimed to review the biomechanical and clinical evidence on AR for MMPRTs. METHODS: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in the International Prospective Register of Systematic Reviews (PROSPERO). MEDLINE, Embase, Scopus, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched. Outcomes included patient-reported outcome measures (PROMs), magnetic resonance imaging (MRI), and biomechanical performance. When available, random-effects meta-analysis was performed. RESULTS: Thirteen studies were included. AR restored contact mechanics and showed load to failure comparable to TP, with lower stiffness. Meta-analysis showed lower conversion to total knee arthroplasty with AR versus non-repair (RR 0.18, 95% CI 0.05-0.58), and no significant PROM differences between AR and TP. CONCLUSIONS: AR showed favorable biomechanical properties and improved outcomes versus non-repair. Compared with TP, no significant clinical differences were observed. AR may represent a reasonable option in selected scenarios.

Humans↗

PubMed2026

Improved donor-site biomechanics and functional recovery with xenogeneic acellular dermal matrix after ALT flap harvest: A prospective randomized controlled study.

BACKGROUND: Donor-site management after anterolateral thigh (ALT) flap harvest is a significant yet underaddressed concern in reconstructive surgery for oral cancer. While xenogeneic acellular dermal matrix (Xeno-ADM) is common in soft-tissue repair, its efficacy for fascia lata reconstruction at the ALT donor site remains insufficiently characterized. This study aimed to assess the efficacy of xeno-ADM in fascia lata repair, focusing on compartment pressure, inflammatory and muscle injury biomarkers, and functional recovery. METHODS: In this prospective, randomized, single-blind trial, 200 patients undergoing ALT flap reconstruction were allocated to Xeno-ADM repair (n = 100) or primary closure (n = 100). Primary endpoints included compartment pressure, inflammatory markers in drainage fluid, serum muscle injury biomarkers, and functional outcomes. RESULTS: The xeno-ADM group showed significantly lower compartment pressures throughout postoperative days (POD) 1-5. Inflammatory markers in drainage fluid (CRP on POD 3 and 5) and serum muscle injury biomarkers (creatine kinase on POD 1 and 5) were significantly lower in xeno-ADM group. Functional outcomes were superior in the Xeno-ADM group, with faster gait recovery, lower pain scores at POD 7, and better lower-limb function at the 1- and 6-month follow-ups. Drainage duration did not differ between groups. Stratified analyses revealed that the benefits of xeno-ADM were more pronounced in patients with defect width >3 cm or a body mass index ≥24 kg/m2. CONCLUSION: Xeno-ADM provides a safe and effective approach for fascia lata repair, reducing biomechanical and inflammatory burdens while enhancing functional recovery. These findings support a transition from simple structural closure toward functional donor-site reconstruction.

Humans↗

PubMed2026

Lower-limb electromyographic responses across four recumbent cycling configurations in healthy young men.

Recumbent cycling provides an adjustable configuration in which backrest angle and crank-axis height can alter lower-limb loading. Backrest angle changes the orientation of the active musculature relative to gravity, whereas crank-axis height modifies the foot-pedal interface and the ankle lever arm. Whether such positioning is associated with differences in lower-limb electromyographic (EMG) activation across both factors together has not been examined. Using a randomized crossover design, fifty-nine healthy young men cycled at 100 W and 50 rpm under four conditions combining two backrest angles (30°, 75°) and two crank-axis heights (Rh, high, 77 cm; Rl, low, 45 cm). Surface EMG from the rectus femoris (RF), biceps femoris (BF), and gastrocnemius medialis (GAS) was analyzed for root mean square (RMS) amplitude, absolute onset sequence, and relative recruitment timing (%Sequence, derived using Telescan software and referenced to RF). RMS amplitude did not differ across conditions for any muscle (all p ≥ 0.356), and absolute onset sequence showed no condition effect (all p ≥ 0.197). For GAS %Sequence, the Greenhouse-Geisser-corrected omnibus test was significant (F(1.32, 76.56) = 28.45, p < 0.001), driven by a within-30° contrast in which %Sequence was lower under Rl than Rh (paired t(58) = 10.39, Holm-adjusted p < 0.0001; mean difference 22.0 percentage points, 95 % CI [17.8, 26.3]; dz = 1.35). Because %Sequence is referenced to RF, this exploratory shift should be interpreted cautiously. Lower-limb activation may be constrained by the closed-chain nature of pedaling, whereas distal recruitment timing may be sensitive to crank-axis height and the foot-pedal interface.

Humans↗

PubMed2026

Mesenchymal Stem Cell-Derived Exosomes Combined With 3-Dimensional Hyaluronan-Based Scaffold Promote Tendon-to-Bone Tunnel Healing.

PURPOSE: Tendon-to-bone healing remains a major clinical challenge due to poor regenerative capacity at the enthesis. This study aimed to evaluate the effects of mesenchymal stem cell-derived exosomes combined with a 3-dimensional hyaluronan-based scaffold on graft healing within bone tunnels. This study was conducted in accordance with the ARRIVE (Animal Research: Reporting of In Vivo Experiments) guidelines. METHODS: A total of 128 tendon-bone models were created in 64 Sprague-Dawley rats, randomized into four groups: control, exosome-only, scaffold-only, and exosome-loaded scaffold. At weeks 4 and 8 postoperatively, samples were analyzed histologically (hematoxylin-eosin, Masson Trichrome), immunohistochemically (fibroblast growth factor 2, bone morphogenetic protein 2), and biomechanically (maximum failure load). RESULTS: At both time points, the exosome-loaded scaffold group demonstrated significantly enhanced vascularization, cellular activity, and collagen fiber continuity and parallelism compared to all other groups (P < .05). Fibroblast growth factor 2 and bone morphogenetic protein 2 expression levels were highest in the exosome-loaded scaffold group, indicating early activation of proregenerative pathways. Biomechanically, this group also exhibited the greatest maximum failure load (15.64 ± 0.86 N at week 4; 22.97 ± 2.86 N at week 8), suggesting superior tendon-to-bone integration. The exosome-only group showed delayed but comparable improvements by week 8. CONCLUSIONS: Combining mesenchymal stem cell-derived exosomes with a 3-dimensional hyaluronan-based polycaprolactone/tricalcium phosphate scaffold enhances early and sustained healing at the tendon-bone interface. This cell-free, biocompatible strategy significantly improves vascularization, growth factor expression, collagen organization, and mechanical strength. These findings support its potential as a clinically translatable approach for improving tendon-to-bone healing outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Animals↗

PubMed2026

Optimizing focal vibration therapy for balance and gait: A systematic review.

OBJECTIVE: This systematic review evaluated the efficacy of focal (localized) vibration therapy (FVT) applied to muscles/tendons on balance, gait, and mobility, with a specific focus on defining optimal vibration protocols (frequency, amplitude, dosing) and muscle-targeting strategies to maximize sensorimotor recovery. METHODS: A systematic review was conducted across six databases (CINHAL, Embase, Medline, Web of Science, Scopus, CENTRAL) from January 2000 to May 2025. Studies were included if they involved human participants, applied FVT therapeutically, and reported balance, gait, or mobility outcomes. Data extraction included study characteristics, intervention protocols, and outcomes. Methodological quality was assessed using the PEDro scale. RESULTS: Sixty-two studies (n = 2090 participants) were included. Methodological quality assessment (PEDro scale) indicated 44% of studies met high-quality standards. Biomechanical analysis identified the quadriceps, gastrocnemius/soleus, and plantar muscles as the most effective vibration sites, given their critical roles in gait propulsion and postural stability. The synthesis of protocol data indicated a promising therapeutic window characterized by a vibration frequency of 80-120 Hz (primarily fixed sinusoidal waveforms at a single frequency) and an amplitude of 0.2-0.5 mm (reported only in 12 studies; amplitude was not reported in 23 studies), applied bilaterally for a minimum of 3 sessions per week over 4-12 weeks, which could lead to improved balance and gait performance with benefits sustained for up to 5 months. CONCLUSION: FVT shows potential to improve gait and balance, particularly when targeting lower-extremity muscles with optimized vibration parameters. To advance the field, future research must prioritize the development of standardized protocols and investigate neurophysiological mechanisms to refine FVT as a precision bioengineering solution for mobility deficits.

Humans↗

PubMed2026

Test-retest reliability of spatiotemporal, kinematic, and kinetic measures in marker-based 3D gait analysis: A systematic review.

BACKGROUND: Marker-based 3D gait analysis (3DGA) is widely used to quantify impairments and evaluate treatment effects. For longitudinal clinical interpretation, clinicians and researchers need reference values for inter-session measurement error. For this purpose, this systematic review synthesized Standard Error of Measurement (SEM) values for spatiotemporal, kinematic, and kinetic (moments) outcomes obtained from marker-based 3DGA studies. METHODS: PubMed and Scopus were searched (final search: 11 December 2025). Studies reporting inter-session test-retest SEM and/or MDC for steady-state overground or treadmill walking using marker-based motion capture were included. Two authors screened records and appraised methodological/reporting quality using a custom tool informed by COSMIN, GRRAS, and biomechanics-specific items. Due to heterogeneity, results were synthesized descriptively using study-level median SEM values, stratified by joint, plane, population (healthy, pathological, single subgroups), and walking condition. Minimal Detectable Change (MDC) values were computed for all available data. RESULTS: Thirty-four studies (762 participants, 44.2% females) were included, with substantially more evidence for overground than treadmill walking. Overground spatiotemporal outcomes showed low errors (walking speed SEM of 0.06 m/s; timing typically ≤0.03 s; spatial parameters generally ≤0.03 m). For joint kinematics during overground walking, median SEMs were 2.4° (sagittal), 1.9° (frontal), and 3.3° (transverse). The corresponding joint-kinetic SEMs were approximately 0.06, 0.04, and 0.03 Nm/kg, respectively. Treadmill data followed similar patterns. SIGNIFICANCE: Marker-based 3DGA allows for accurate assessment of spatiotemporal, kinematic, and kinetic gait features. We provided detailed SEM/MDC lookup tables to support clinical decision-making. Results further offer a benchmark for validating emerging gait assessment technologies (e.g., markerless systems) against realistic limits of marker-based 3DGA.

Humans↗

PubMed2026

The effect of hip abductor or external rotator strength on dynamic knee valgus in healthy subjects-a systematic review with partial meta-analysis.

BACKGROUND: Weak hip abductors and external rotators (ER) have long been suggested to cause increased dynamic knee valgus. Patients are often prescribed strengthening of these muscles with the expectation that it will reduce their risk of pain and injury. The validity of this claim remains unclear. METHOD: We conducted a systematic review and partial meta-analysis assessing the association between hip strength and knee valgus in healthy subjects. An online search was conducted in May 2026. Databases included Medline, EMBASE, CINAHL and Google Scholar. INCLUSION CRITERIA: English language, asymptomatic subjects, dynamometric hip strength, single or multi-camera kinematic analysis, and statistical tests of difference or correlations between hip abductor or ER strength and dynamic valgus. Data were extracted concerning study design, subject characteristics, relevant outcome measures and statistics. RESULTS: 22 papers qualified for inclusion. Hip abductor correlations: 12 papers found no significant correlation, 2 supported the hypothesis and 2 found evidence contrary. Hip ER correlations: 8 papers found no significant correlation, 2 supported the hypothesis and 2 were contrary. Group differences for hip abduction strength: 3 papers found no difference, 2 found significant differences in support of the hypothesis, 1 found significant difference to contrary. Group differences for ER strength: 1 paper found no significant difference. None of the partial meta-analyses achieved statistical significance. CONCLUSION: Weakness in hip abductors or external rotators may not result in increased dynamic knee valgus in healthy subjects. While continued research may further illuminate our understanding, we discuss alternative explanations.

Humans↗

PubMed2026

Alignment strategies in total knee arthroplasty and the patellofemoral joint: A systematic review.

BACKGROUND: Different alignment strategies in total knee arthroplasty (TKA) may affect the patellofemoral joint. Mechanical alignment (MA) is commonly used but may alter native anatomy. Newer strategies such as kinematic alignment (KA), restricted kinematic alignment (rKA), and functional alignment (FA) aim to better restore native joint mechanics. This study provides an overview of the effects of alignment strategies on patellofemoral outcomes after TKA. METHODS: A literature search in July 2025 identified studies comparing patellofemoral outcomes in TKA using different alignment strategies. Of 166 studies screened, eight met inclusion criteria. Three studies were considered medium quality and five studies low quality. RESULTS: KA and rKA more closely restored native trochlear morphology than MA and FA, reducing outliers in the anterior trochlear line compared with MA and FA. MA showed greater trochlear translation, suggesting worse patellar tracking. Trochlear angles were more anatomical in KA and rKA. However, KA was associated with increased internal femoral component rotation and more outliers beyond safe thresholds. FA showed more consistent rotational positioning, generally within safe limits. Lateral patellar shift and intraoperative lateral release rates did not differ significantly between KA and MA. Only one study reported patella-specific clinical outcome scores, finding no difference between FA and adjusted MA. CONCLUSION: KA and rKA better restore trochlear morphology, but risk excessive internal femoral component rotation. FA provides a more balanced approach. MA, while widely used, is linked to altered trochlear shape and worse patellar tracking. The clinical impact of these radiological differences remains unclear, and higher-quality studies are needed.

Humans↗

PubMed2026

The knee-ankle link: impact of knee varus severity on distal joint malalignment and concomitant pathologies.

BACKGROUND: Knee varus deformity is traditionally managed as an isolated joint pathology; however, persistent distal symptoms following proximal realignment suggest a more extensive kinetic chain dysfunction. The degree to which knee varus severity dictates distal malalignment and secondary pathologies remains poorly quantified in the current literature. METHODS: This systematic review and meta-analysis were conducted in accordance with PRISMA 2020 guidelines (PROSPERO: CRD420261363327). A comprehensive search of PubMed, Embase, Web of Science, and the Cochrane Library was performed from inception to April 2026. Studies examining the relationship between knee varus (HKA angle) and radiographic distal alignment or pathologies were included. Data synthesis utilized random-effects models, with prevalence analyzed via generalized linear mixed models (GLMM). RESULTS: Fourteen studies were included in the final synthesis. While pooling of continuous radiographic parameters was limited by high statistical heterogeneity in Talar Tilt (I2 = 96.5%), individual large-cohort data (Huang et al.) indicated that severe knee varus (HKA > 10°) was associated with increased odds of concomitant ankle osteoarthritis (OR 2.29; 95% CI 1.28-4.11) and a specific cohort prevalence of 37.1%. Furthermore, single-arm prevalence data revealed divergent trends across different study populations, with compensatory hindfoot valgus reaching 69.9% in some cohorts and rigid varus up to 63.9% in others. CONCLUSIONS: Severe genu varum is associated with distal kinetic chain alterations and concomitant ankle pathologies. However, due to the extreme heterogeneity and divergent distal adaptations observed across different cohorts, standardized knee-centric protocols may be insufficient. Further longitudinal and interventional studies are required to establish phenotype-specific rehabilitation guidelines.

Humans↗

PubMed2026

Muscle mechanical and architectural adaptations in response to different endurance training modalities in older adults.

INTRODUCTION: This study examined the effects of various cycling endurance training modalities, matched for total workload, on muscle mechanical and architectural characteristics in older adults. METHODS: Fifty healthy participants (25 females, 59-79 yrs) were randomly assigned to five age and sex matched groups: one control and four workload-matched training groups (moderate-intensity continuous, heavy-intensity continuous, high-intensity interval, and heavy-intensity continuous in eccentric cycling). Training consisted of three weekly sessions over 8 weeks, with evaluations conducted at the beginning and end of the intervention with maximal voluntary isometric contractions at five different knee angles (90, 75, 60, 45, 30°) and maximal concentric and eccentric isokinetic contractions at five different knee angular velocities (45, 90, 150, 210, 250°/s). Maximum voluntary isometric torque (Tmax) and optimal knee angle (KAopt) were obtained from the isometric contractions; eccentric torque (Tecc) and maximum concentric knee angular velocity (Vmax) were obtained from the isokinetic contractions. The muscle architecture of vastus lateralis (VL) at rest (muscle thickness, pennation angle, and fascicle length) was investigated as well. RESULTS: No statistical differences were detected between groups or time points in VL architecture, in KAopt and in Vmax. A main effect of time was observed for Tmax (p < 0.001, η2p = 0.458) and Tecc (p = 0.002, η2p = 0.191) in all the investigated training groups. The within-group comparisons indicate significant increases in Tmax in the training groups, but not in the control group. CONCLUSIONS: Commonly applied endurance exercises improve muscle mechanical capacity (Tmax and Tecc) in older adults, with no structural (architectural) muscle remodelling, when matched for workload.

Humans↗

PubMed2026

Effects of Dynamic Neck Sensorimotor Biofeedback Training in Individuals With Mechanical Neck Pain: A Pilot Randomized Controlled Trial.

Mechanical neck pain (MNP) is commonly accompanied by pain-related functional limitations, sensorimotor disturbances, and fear of movement, which together may contribute to persistent disability. This preliminary randomized controlled trial study investigated the short-term effects of dynamic neck sensorimotor-based biofeedback training in individuals with MNP. 20 MNP patients from outpatient clinics were assigned to a biofeedback training group or a control group. The training group underwent dynamic biofeedback exercises twice weekly for 2 weeks, whereas the control group performed repeated cervical movements without biofeedback. Outcomes included cervical kinematics as repositioning errors (RPE), movement units (MU), maximal range of motion (ROM), and subjective measures, including pain intensity, Neck Disability Index (NDI), and Fear-Avoidance Beliefs Questionnaire (FABQ). All participants completed post-intervention assessments; adherence in the training group was 100%, with no missing data and no adverse events reported. Within the biofeedback training group, participants receiving biofeedback training demonstrated greater improvements in cervical repositioning accuracy during flexion (51.95%, p = 0.04) and extension (46.67%, p = 0.02), along with reductions in fear-avoidance beliefs related to physical activity and work (p < 0.05); these changes were less apparent in the active control group. Exploratory regression analyses suggested associations between improvements in repositioning accuracy and pain reduction, and between increased cervical range of motion and improvements in fear-avoidance beliefs related to physical activity. These pilot findings suggest that dynamic sensorimotor biofeedback training may improve proprioceptive acuity and fear-avoidance beliefs in individuals with MNP, supporting further evaluation in an adequately powered randomized trial.

Humans↗

PubMed2026

Effects of carbohydrate mouth rinse on psychophysiological responses, kinematic variables and technical actions during small-sided soccer games.

BACKGROUND: This study investigated the effects of carbohydrate mouth rinsing (CHOMR) on various psychophysiological, kinematic, and technical actions during 4-a-side small-sided soccer games (SSGs). METHODS: In a randomized, crossover, double-blind design, 16 young male soccer players (age: 15 ± 1 years; height: 172.6 ± 7.0 cm; body mass: 57.8 ± 7.9 kg) participated in two 4-a-side SSGs separated by one week following either CHOMR or placebo (PLA). During each SSGs, heart rate (HRmean, %HR, and HRmax), rating of perceived exertion (RPE), enjoyment, visual analogue scale (VAS) to perceived mental fatigue, mood states, total distance (TD), high-speed running distance (HSRD), average metabolic power (AMP), high metabolic load distance (HMLD), sprint distance (SD), acceleration (ACC), deceleration (DEC), and technical actions (e.g. passing, tackling, shooting, and interceptions) were assessed. RESULTS: Compared with PLA, CHOMR resulted in significantly higher RPE (p = 0.025, g = 0.86) and significantly lower VAS scores (p = 0.010, g = -0.71). In addition, the CHOMR condition showed significantly higher values for interceptions, successful tackles, unsuccessful tackles, unsuccessful shots, and goals (p < 0.05, g = 0.96-2.02), whereas block values were significantly higher in the PLA condition. There were no statistically significant differences in HRmean, %HR, HRmax, enjoyment, TD, HSRD, AMP, HMLD, SD, ACC, DEC, successful passes, unsuccessful passes, successful shots, or mood states between the conditions (p > 0.05). CONCLUSION: The current study findings suggest that CHOMR may enhance selected technical actions and lower VAS scores during 4-a-side SSGs, although it was also associated with higher RPE and did not alter the kinematic responses. In conclusion, CHOMR was associated with higher RPE, lower mental fatigue, and selective improvements in technical actions, with no significant effects on kinematic variables or HR.

Humans↗

PubMed2026

Effects of an actuated ankle exoskeleton on walking stability in healthy adults: a controlled laboratory study.

BACKGROUND: Ankle exoskeletons are widely used to reduce the metabolic cost of walking, yet their effects on walking stability during unperturbed gait remain insufficiently understood. Walking stability can be characterized using complementary measures that capture stride-to-stride variability, global temporal organization, and local dynamic stability. Understanding how walking with an actuated ankle exoskeleton system influences these different aspects of gait stability is essential for the safe design and control of wearable robotic devices. METHODS: Eighteen healthy adults walked on a treadmill at a constant speed (1.1 m/s) with and without an actuated bilateral ankle exoskeleton in a randomized crossover design. Spatiotemporal variability was quantified using coefficients of variation (CoV) of stride length, step width, and stance ratio. Global gait stability was assessed using detrended fluctuation analysis of stride time. Local dynamic stability was evaluated using maximum Lyapunov exponent calculated for the trunk, hip, upper leg, lower leg, and foot. Paired-samples two-sided t-tests were used to compare conditions. RESULTS: Walking with the ankle exoskeleton resulted in increased stride-to-stride spatiotemporal variability, reflected by higher CoV values for stride length (p < 0.001) and stance ratio (p = 0.005), while mean stride length and step width remained unchanged. Mean stance ratio was reduced in the exoskeleton condition (p < 0.001). Global gait stability did not differ between conditions, indicating preserved long-range temporal gait organization. Local dynamic stability increased at the lower leg (p < 0.001) and foot (p = 0.019) when walking with the exoskeleton. CONCLUSIONS: Walking with the actuated ankle exoskeleton alters gait control across multiple levels during steady walking. While stride-to-stride variability in stride length and stance ratio increased, global gait stability remained unchanged. Local dynamic stability was increased at the lower leg and foot, suggesting segment-specific effects of ankle-level assistance close to the assisted joint. However, these findings should be interpreted as the combined effect of wearing the exoskeleton and receiving active assistance, rather than the isolated effect of plantarflexion assistance. These results provide insight for the design and control of ankle exoskeletons with respect to stability-related effects during walking.

Humans↗

PubMed2026

Meniscal preservation in the age of biologics: toward a quantitative decision algorithm for personalized repair.

BACKGROUND: Despite advances in arthroscopic repair and biologic augmentation, surgical indication for meniscal tears remains heterogeneous. No standardized framework currently integrates biomechanical, clinical, and biological determinants to guide repair versus resection. PURPOSE: To develop a quantitative decision model-the Meniscal Preservation Score (MPS)-that unifies biomechanical and biological evidence to stratify reparability potential and standardize treatment selection in meniscal surgery. METHODS: A systematic evidence synthesis conducted in accordance with PRISMA 2020 reporting standards of studies published from 2000 to 2025 in PubMed, Embase, and Scopus identified key determinants of meniscal healing. Five consistent predictors-patient age, vascularity, tear morphology, associated pathology, and activity profile-were weighted through a two-round modified Delphi consensus among ten experienced knee surgeons. The resulting 0-9-point MPS was incorporated into a stepwise decision tree linking lesion morphology, biological context, and surgical strategy. Conceptual validation used 50 simulated cases and a retrospective cohort of 45 patients to test agreement between algorithm recommendations and expert surgical decisions. RESULTS: The MPS achieved 86% concordance with expert judgment in simulation and 84% agreement in clinical validation. In this retrospective exploratory cohort, cases in which surgical management was concordant with MPS recommendations demonstrated higher mean IKDC scores at 24 months and lower observed reoperation rates. These findings should be interpreted as associative rather than causal, as treatment allocation was not controlled and discordant cases may have represented inherently more complex pathology. CONCLUSION: The MPS represents an evidence-informed decision-support framework designed to systematize reparability assessment. While exploratory analyses suggest structural coherence with expert reasoning, prospective implementation and external validation are required before clinical adoption as a predictive tool. LEVEL OF EVIDENCE: conceptual model with exploratory validation.

Humans↗

PubMed2026

Diagnostic criteria and severity assessment for syndesmosis injury using magnetic resonance imaging: A systematic review.

High ankle sprains involving syndesmosis injury present challenges in both diagnosis and severity assessment. Magnetic resonance imaging is widely regarded as the preferred modality for evaluating syndesmosis injury and related structural damage. This systematic review primarily examined the diagnostic utility of magnetic resonance imaging. Secondarily, it explores grading and prognostics of syndesmosis injuries with magnetic resonance imaging and identified possible imaging parameters predictive of injury severity. A comprehensive search of MEDLINE, Embase, CINAHL Complete, and Scopus was performed through February 12, 2025, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Peer-reviewed human studies in English that used magnetic resonance imaging to assess syndesmosis injury were included. Excluded were review articles, case reports, abstract-only studies, and biomechanical or cadaveric investigations. Twenty-seven studies comprising 1931 ankles met inclusion criteria. Magnetic resonance imaging demonstrated high diagnostic accuracy for complete tears of the anterior and posterior inferior tibiofibular ligaments. Ancillary signs such as the ring-of-fire edema pattern, distal tibiofibular joint effusion, and widening of the distal joint space exhibited high specificity with variable sensitivity and may assist in grading injury severity. Magnetic resonance imaging in chronic syndesmosis injury primarily detects fibrotic scarring and post-injury changes. Evidence gaps remain regarding the parameters that best determine injury severity and indicate early surgical intervention in competitive athletes. Consolidating multiple magnetic resonance imaging findings into standardized diagnostic criteria may improve reliability and clinical decision-making.

Humans↗

PubMed2026

Sex-stratified analyses of femoral intercondylar notch morphology and ACL injury risk: a systematic review and meta-analysis.

BACKGROUND: Anterior cruciate ligament (ACL) injury is more common in females. Although ACL injury risk is multifactorial, involving neuromuscular, hormonal, and biomechanical factors, femoral intercondylar notch morphology is a proposed non-modifiable anatomical contributor that may help explain this disparity. This review synthesizes evidence on its association with ACL injury risk, analyses stratified by male and female sex. METHODS: A literature search of PubMed, Web of Science, and Scopus was conducted through January 2026. After duplicate removal, 527 unique records were screened and 134 full texts assessed for eligibility. Twenty-four studies met inclusion criteria, with 22 providing quantitative data. Data were extracted on ACL-injured (ACLi) and control (ACLc) knees, stratified by sex. RESULTS: ACLi knees had narrower notch widths than ACLc knees in both females (MD -1.74 mm, 95% CI -2.54 to -0.95) and males (MD -1.31 mm, 95% CI -1.94 to -0.68), with substantial heterogeneity (I2 81-95%). NWI differences were significant in males (MD -0.01, 95% CI -0.02 to 0.00) but not females. Limited notch shape data suggested higher ACL injury odds with A-shaped notches in females (OR 2.85, 95% CI 0.07-110.66) and males (OR 1.67, 95% CI 0.00-3.98 × 105). CONCLUSION: Narrower femoral intercondylar notch width was consistently associated with ACL injury in both sexes, whereas findings for NWI and notch shape were limited by heterogeneity and sparse data. These results provide a structured synthesis of sex-specific anatomical risk factors and support femoral notch narrowing as a shared contributor, while highlighting the need for prospective, standardized studies in the future.

Humans↗