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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

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

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

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

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&#xa0;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&#xa0;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&#xb0;) and maximal concentric and eccentric isokinetic contractions at five different knee angular velocities (45, 90, 150, 210, 250&#xb0;/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&#xa0;<&#xa0;0.001, &#x3b7;2p&#xa0;=&#xa0;0.458) and Tecc (p&#xa0;=&#xa0;0.002, &#x3b7;2p&#xa0;=&#xa0;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

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&#xa0;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&#xa0;=&#xa0;0.04) and extension (46.67%, p&#xa0;=&#xa0;0.02), along with reductions in fear-avoidance beliefs related to physical activity and work (p&#xa0;<&#xa0;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

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&#x2009;&#xb1;&#x2009;1 years; height: 172.6&#x2009;&#xb1;&#x2009;7.0&#x2009;cm; body mass: 57.8&#x2009;&#xb1;&#x2009;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&#x2009;=&#x2009;0.025, g&#x2009;=&#x2009;0.86) and significantly lower VAS scores (p&#x2009;=&#x2009;0.010, g&#x2009;=&#x2009;-0.71). In addition, the CHOMR condition showed significantly higher values for interceptions, successful tackles, unsuccessful tackles, unsuccessful shots, and goals (p&#x2009;<&#x2009;0.05, g&#x2009;=&#x2009;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&#x2009;>&#x2009;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