Rupture of the anterior cruciate ligament is a well-known cause of knee instability. However, even after reconstruction, some patients continue to experience residual instability, which has raised interest in the anterolateral ligament as a secondary stabilizer of the knee. This study aimed to investigate in-vivo knee kinematics during level walking after combined single-bundle anterior cruciate and anterolateral ligament reconstruction to assess restoration of normal knee kinematics. Ten individuals who underwent combined reconstruction and ten healthy controls participated in treadmill gait trials using a biplanar fluoroscopic imaging system. The subject-specific 3D model and tibiofemoral kinematics were reconstructed using a statistical shape and intensity model and 2D3D registration. Tibial kinematics were compared among operated, contralateral, and healthy knees using statistical parametric mapping and a cumulative-change analysis. The operated knees exhibited significantly increased anterior tibial translation throughout 17-85% of the stance phase compared with both contralateral and normal knees (p < 0.05). Internal tibial rotation was also significantly greater in operated knees during early stance (15-37%) compared with normal knees. Cumulative changes in internal-external rotation and anterior-posterior translation during early stance were significantly increased in operated knees than in contralateral and normal knees. Anatomical single-bundle reconstructions combined with anterolateral ligament reconstruction do not fully restore normal joint kinematics. Increased anterior translation and internal rotation persist, indicating residual instability. These findings support rotational laxity of single-bundle techniques and suggest the potential need to address dynamic instability.
Manual wheelchair use supports independence and participation for children with neuromuscular disorders; however, pediatric propulsion biomechanics remain poorly defined. Clinical practice often relies on adult data despite developmental differences in growth, motor control, and endurance. A pediatric-specific synthesis is needed to inform wheelchair prescription, training, and shoulder preservation strategies. This scoping review aimed to map biomechanical outcomes, methods, and propulsion protocols in pediatric manual wheelchair users with neuromuscular disorders, while identifying clinical implications and research gaps. A scoping review following PRISMA-ScR guidelines was conducted using PubMed and Embase through August 2025. Eligible studies included individuals ≤18 years with neuromuscular conditions using manual or power-assist wheelchairs and reporting at least one biomechanical outcome. Data were extracted on study design, populations, measurement tools, propulsion tasks, and key findings. Methodological quality was also assessed. Seventeen studies met inclusion criteria, most involving pediatric-onset spinal cord injury, with fewer including spina bifida, cerebral palsy, muscular dystrophy, or Charcot-Marie-Tooth disease. Three domains emerged: (1) upper extremity mechanics: children experienced substantial shoulder loading (6-10% body weight), distinct kinematics, and high interindividual variability; (2) propulsion efficiency: smaller contact angles, higher cadences, and less mature stroke patterns were common, though brief training improved efficiency; and (3) physiologic cost: limited evidence indicated high metabolic demand, with VO2 during the 6-Minute Push Test reaching 85-89% of VO2peak in myelomeningocele. Pediatric propulsion is biomechanically demanding and developmentally distinct, emphasizing the need for pediatric-specific training and early shoulder-preservation strategies. Key research gaps include broader diagnostic representation, standardized protocols, seating-interface biomechanics, and longitudinal outcomes.
Variations in femoral offset have been shown to affect postoperative gait biomechanics, but their specific impact and temporal progression remain unclear. This study examined the effect of femoral offset on gait biomechanics within 12 months following total hip arthroplasty. This prospective study compared 120 patients with diagnosed hip osteoarthritis who underwent primary total hip arthroplasty, categorized into three groups based on the reconstructed three-dimensional model's 3 dimensions femoral offset differences before and after total hip arthroplasty: large femoral offset (>5 mm), small femoral offset (<5 mm), or normal femoral offset (+5 to -5 mm). Gait biomechanics were assessed using three-dimensional instrumented gait analysis. Group differences in hip kinematics were analyzed using statistical parametric mapping. Step length exhibited a significant group effect, as it was significantly greater in the larger femoral offset group than in the small femoral offset group (P = 0.026). The small femoral offset group exhibited significantly greater hip extension between 62 and 68% (P = 0.048) of the gait cycle compared to the normal group after 10 days. The large femoral offset group demonstrated significantly greater hip flexion between 67 and 94% (P < 0.001) of the gait cycle than the small femoral offset group after 3 months. Reduced femoral offset reconstruction may adversely influence step length and early postoperative gait kinematics. These findings suggest that under-restoration of femoral offset may impair early postoperative gait recovery, highlighting the importance of appropriate femoral offset restoration during THA.
Midfoot break deformity is common in children with cerebral palsy, presenting as extreme planovalgus, with midfoot dorsiflexion. Muscle imbalance, particularly between tibialis posterior (tib-post) and tibialis anterior (tib-ant), is frequently blamed. Recent work has shown that midfoot break is associated with an altered subtalar joint axis orientation but the impact on dynamic moments and moment arms remains unknown. This pilot study aims to determine whether a novel methodology for determining subtalar joint biomechanics reveals clinically important biomechanical differences in a sample of children with midfoot break compared with typically developing children, informing future trial design. Weight-bearing cone-beam CT scans of the foot and ankle were obtained, and gait analysis conducted on nine typically developing children and six with midfoot break. Personalized musculoskeletal models were generated. Subtalar joint moments were calculated and muscle moment arms of tib-post and tib-ant estimated throughout the gait cycle. The novel methodology successfully identified differences between children with midfoot break and typically developing children. Five out of six children with midfoot break exhibited significantly larger everting subtalar joint moments for at least part of the gait cycle, with ground reaction force moment arms 60% greater. Tib-ant acted as a stronger evertor for those with midfoot break and tib-post had significantly lower inverting moment arms for four midfoot break children. This novel methodology has demonstrated a relationship between subtalar joint alignment and midfoot break, revealing biomechanical pathways which may be contributing to the development of the deformity in children with cerebral palsy.
While knee osteoarthritis (OA) is incurable, end-stage OA can be managed surgically with partial knee arthroplasty (PKA) or total knee arthroplasty (TKA). Most studies that compare PKA and TKA cohorts rely on patient-reported outcome measures (PROMs) and lack objective joint-level biomechanics. The purpose of this study was to examine preoperative joint-level kinematics during multiple functional tasks including preferred-pace walking, fast-paced walking, and sit-to-stand alongside self-reported outcomes in patients that received partial versus total knee arthroplasty. Participants with end-stage knee osteoarthritis were recruited from St. Joseph's Healthcare Hamilton. Self-reported measures included the Oxford knee score, pain ratings, quality of life, and depression. Functional tasks were recorded using markerless motion capture, and joint-level kinematics were analyzed with linear mixed models to test main and interaction effects of surgery type and task condition. The study included 15 patients that received partial knee arthroplasty and 56 patients that received total knee arthroplasty. No significant differences were observed in self-reported outcomes, nor in single-speed gait or sit-to-stand performance. However, differences emerged when examining walking patterns across speeds. Compared to the total knee arthroplasty group, patients that received partial knee arthroplasty demonstrated greater changes in stride length, peak stance and swing knee flexion, knee excursion, peak stance hip flexion, and overall hip range of motion when going from preferred- to fast-paced walking. These findings suggest that multi-speed gait assessments may provide a more sensitive approach to detecting kinematic differences in osteoarthritis patients and may be valuable in other clinical contexts.
Non-specific chronic low back pain (NSCLBP) is a multifactorial condition associated with disability and reduced quality of life. Telerehabilitation may enhance access to exercise-based care; however, existing evidence is heterogeneous, and objective outcome assessments are often limited. This study evaluated the effects of a six-week telerehabilitation program in 21 adults with NSCLBP (16 females; 32-80 years) assessing clinical information and motor performance before and after the intervention. Wearable measurements, including inertial sensors and surface electromyography, were collected during five tasks: Timed Up and Go, Sit-to-Stand, and three NSCLBP-specific exercises. Depending on the data distribution, paired t-tests or Wilcoxon signed-rank tests were applied. Effect sizes, 95% confidence intervals, and false discovery rate (FDR) adjustments were also reported. Disability and functionality scores improved significantly, whereas pain and kinesiophobia did not change. Surface electromyography parameters showed significant pre-post changes during Timed Up and Go, Sit-to-Stand, and NSCLBP-specific exercises, whereas inertial sensors metrics exhibited minor pre-post changes. The six-week telerehabilitation program resulted in clinically meaningful improvements in disability and function. Wearable-based assessments provided complementary, objective insights into neuromuscular and movement-related changes. Informal patient feedback indicated that this digital approach is both feasible and acceptable.
This review synthesizes current literature on the use of artificial intelligence (AI) to predict knee biomechanics during walking in people with knee osteoarthritis (OA). Four databases were searched from inception to 22/01/2025. Risk of bias was assessed using a modified Newcastle-Ottawa Scale. Study quality was assessed using Grading of Recommendations, Assessment, Development, and Evaluations. Gait spatiotemporal parameters, knee kinematics, knee kinetics, and knee internal biomechanics calculated with both AI and physics-based methods were compared using root mean squared error (RMSE), normalized RMSE (NRMSE), mean absolute error (MAE) with standard deviation (SD), or correlation coefficients (R2), and pooled for reporting. Of 883 studies screened, 8 were included for review, and four provided appropriate data for meta-analysis. Studies ranged from very low to high quality. Limited data were available for spatiotemporal parameters, with few studies including direct physics-based comparators. AI-predicted knee flexion time-series had RMSE ranging from 8.39 ± 4.13° to 8.81 ± 4.25° across the gait cycle. Meta-analysis found AI-predicted peak knee adduction moment was highly correlated with its physics-based counterpart (R2: 0.86 and 0.60) with moderate errors (MAE: 0.37 and 0.45) and mean differences 0.03%BW*Ht [95% CI: -0.08 to 0.14]). AI-predicted peak knee contact forces (medial, lateral, and total) had correlations ranging from R2 = 0.17 to 0.92, and NRMSE varied between 0.21 (0.01) and 0.70 (0.05) relative to physics-based values. Overall, AI approaches have potential to predict specific knee biomechanics, but refinement and validation are needed to improve prediction accuracy across all knee biomechanical variables.
To establish a 2D biomechanical finite element model of a pathological pelvic floor and explore mechanisms driving pelvic organ prolapse (POP) progression from mild to severe stages based on a Stage I POP-Q patient. We developed a two-dimensional biomechanical finite element model based on the clinical presentation of a patient with POP-Q stage I prolapse at rest. The biomechanical interactions between the morphological characteristics and mechanical support were investigated by considering the effects of genital hiatus, intra-abdominal pressure, and combined injuries. A more severe prolapse occurred on the pelvic floor during a resting genital hiatus, with an abdominal pressure of 83. 9 cmH2O and a posterior vaginal wall injury rate of 75%. However, when the genital hiatus changed from a resting state to a prolapsed state, the uterus and the anterior vaginal wall prolapsed from the orificium vaginae. Compared to the case of a resting genital hiatus, a prolapsed genital hiatus results in a 101. 6% and 56. 9% increase in the maximum downward displacement of the cervix and mid-portion of the anterior vaginal wall, respectively. Under the influence of combined injuries, abdominal pressure and the prolapsed genital hiatus, the pathologic pelvic floor may progressively evolve from mild prolapse to moderate or severe prolapse of the anterior vaginal wall and bladder, as well as the uterus. The overall morphological characteristics are dominated by downward prolapse displacement. The combined force directs downward toward the orificium vaginae and the main mechanical support gradually shifts to the perineal body.
Trunk movement plays a vital role in daily activities, influencing efficiency, balance, and musculoskeletal health-especially in individuals with neurological conditions. However, three-dimensional (3D) motion analysis of the trunk lacks standardisation, limiting both cross-study comparisons and clinical application. This review synthesises current approaches to trunk modelling, including marker setups, segment definitions, and kinematic outcomes, in studies involving participants with neurological conditions. A systematic search of six databases, including MEDLINE and Scopus, was conducted (June 2021, updated October 2025i) without date restrictions. Eligible studies assessed 3D trunk kinematics using marker-based systems in participants of any age with neurological or neuromuscular conditions. Extracted data included marker configurations, task types, segment definitions, and reported kinematic outcomes. Fifty-eight studies met the inclusion criteria. Over half (51.72%) modelled the trunk as a single segment, 43.1% focused solely on the upper trunk, and only one study used a multi-segmental model. The most reported movements were flexion-extension (n = 40), lateral bending (n = 29), and axial rotation (n = 28). Overall, gait analysis studies used more markers on the spine but still reported the trunk as a single segment. Marker configurations and outcome metrics reported varied significantly for similar tasks, highlighting a lack of standardisation. Standardised marker setups and segment definitions are essential for improving comparability and clinical relevance. Although multi-segmental models provide deeper insights into compensatory movement patterns, they remain underused. Future research should focus on refining trunk modelling techniques and assessing their impact on rehabilitation to enhance objective clinical evaluation of interventions and disease progression.
Accurate classification of gait patterns in children with cerebral palsy (CP) is critical for guiding treatment but requires expert interpretation of data. Automated methods have potential to improve consistency and scalability; however, clinically meaningful automated tools are limited. This work aimed to determine if automated algorithms based on established gait classifications can reproduce expert clinical classification in children with CP. An automated MATLAB algorithm was developed to assign gait classifications using two established systems (Rodda & Graham and Rozumalski & Schwartz). A sample of children with CP who met criteria for crouch gait underwent automated classification. Three expert gait analysts independently classified all trials using standardized definitions corresponding to each system. Fleiss's κ quantified inter-rater reliability, while Cohen's κ, weighted κ, percent agreement, and macro F1 scores quantified agreement between each reviewer and the automated classifications. Inter-rater reliability among reviewers was substantial for Rodda & Graham (κ = 0.753), with high agreement between reviewers. Inter-rater reliability among reviewers was moderate for Rozumalski & Schwartz (κ = 0.456) and agreement between raters was lower and more variable, with some classifications demonstrating full disagreement among reviewers. Automated gait classification based on quantitative gait criteria can achieve agreement with gait analysis experts for systems with clear biomechanical boundaries. More complex cluster-based systems yield lower agreement, reflecting inherent ambiguity in cluster overlap. These findings support use of automated tools as reliable, objective ground-truth for large-scale analyses and for training markerless or video-based assessment algorithms aimed at expanding gait evaluation beyond specialized motion laboratories.
Cooper's ligaments tether the dermis to the pectoral fascia and play a key role in breast suspension, but they are still poorly represented in finite element (FE) models used for surgical planning. This work proposes a patient-specific computational framework that explicitly incorporates anatomically informed Cooper's ligament networks into three-dimensional breast FE models. The pipeline combines automatic magnetic resonance imaging (MRI)-based tissue segmentation with deep learning, cadaveric anatomical observations, and multi-component FE simulations in Abaqus. A synthetic three-dimensional ligament network is derived from published anatomical descriptions and cadaveric dissection, and modelled as beam elements embedded within volumetric soft tissue domains (skin, adipose, and glandular tissue) equipped with Neo-Hookean hyperelastic constitutive laws. Three ligament configurations (absent, simplified radial, and anatomically distributed) were compared under gravity while varying ligament stiffness between 0.1 and 10 MPa. The anatomically distributed network reduced the maximum displacement from 30.88 mm to 19.05 mm, shifted internal stress from the skin envelope to the ligamentous scaffold, and showed a nonlinear stiffness-displacement response with limited benefit beyond approximately 2 MPa. Ligament architecture has a major influence on predicted breast biomechanics and should not be reduced to a coarse radial pattern. The proposed framework is compatible with standard clinical MRI and FE tools and provides a basis for extending patient-specific breast models towards more reliable preoperative planning for reconstruction.
Anterior shoulder instability may impact daily physical activities, particularly those requiring movements above shoulder level, and is typically treated with stabilizing surgery. However, quantification of the shoulder function during activities of daily living, both before and after a shoulder stabilizing surgery, is unknown. The aim was to evaluate daily shoulder activity in patients with anterior shoulder instability before and after stabilizing surgery using inertial measurement units. Thirty-two patients with unilateral anterior shoulder instability scheduled for shoulder stabilizing surgery were enrolled. Bilateral shoulder activity and patient-reported outcomes were obtained preoperatively and one year postoperatively using inertial measurement unit sensors over one or two days. Inertial measurement unit outcomes, including position, motion frequency, velocity, and acceleration, were compared using mixed model analysis. No significant differences in daily shoulder activity from pre- to postoperatively were found between the injured and healthy shoulders for any outcome measure. However, one year postoperatively, patients achieving improvements above the minimally clinically important difference in Disabilities of Arm, Shoulder and Hand questionnaire tended to spend 1.7 percentage points more time at velocities above 30 deg./s (95%CI 1.0; 3.6) than those below the minimally clinically important difference. Daily shoulder activity was generally low, with limited use above shoulder level. No differences were found in daily shoulder activity between the healthy and injured shoulders in patients with anterior shoulder instability from pre- to postoperative. Future studies should incorporate velocity measures and longer monitoring periods or focus on disease-specific activities to detect subtle changes in shoulder activity.
Visual impairments (VI) affect over 2.2 billion people worldwide and are linked to an increased risk of falls. To date, no reviews have systematically synthesised evidence for the effect of VI on whole body gait biomechanics, to better understand how different types of VI might affect gait. A systematic search up to July 2025 was conducted using PubMed (MEDLINE), Scopus, Web of Science, and ERIC. Eligible studies included adults, a diagnosed or simulated VI, a non-visually impaired comparator, and reported any of the following gait parameters: 1) Spatio-temporal; 2) Kinetics; 3) Kinematics; and 4) Muscle activity. Study quality was evaluated using quality assessment with diverse studies (QuADS) and a narrative synthesis undertaken (SWiM). Forty-four studies were included. Twenty-seven examined straight-line level walking, 12 examined obstacle walking and five examined both straight-line level and obstacle walking. Of those examining straight-line level walking, 12 simulated VI and 15 explored diagnosed VI's. In the obstacle walking literature, nine simulated VI and six included participants with diagnosed VI's. Inconsistent findings were common across studies, with most reporting either a more cautious gait strategy with VI, or no difference between VI and non-VI conditions. Differences between studies are likely explained by variation in gait measurement, non-standard VI simulation methods, and lack of detail surrounding the severity of diagnosis. This hinders provision of clinical recommendations based on existing evidence. We have proposed minimum reporting requirements around acuity, contrast sensitivity, visual field method/thresholds; simulation validation to facilitate clinical utilisation.
Effective wound management requires rapid hemostasis and efficient healing. Calcium chloride (CaCl2)-crosslinked hydrogels are emerging as promising biomaterials that combine structural stability with bioactivity. This review aims to elucidate the hemostatic mechanisms, cellular interactions, and clinical potential of CaCl2-crosslinked hydrogels, while addressing the challenges and future directions for their application in wound care. A narrative synthesis of recent studies was conducted, focusing on the composition, crosslinking mechanisms, and biological functions of these hydrogels. Comparative analyses with alternative materials and innovations to overcome current limitations are also included. CaCl2-crosslinked hydrogels demonstrate superior hemostatic performance, defined as the ability to accelerate clot initiation, enhance platelet adhesion and aggregation, lower the blood clotting index, and reduce blood loss. This is achieved by stabilizing fibrin networks, activating clotting factors (II, VII, IX, X), and promoting platelet aggregation. Calcium ions regulate keratinocyte proliferation, fibroblast differentiation, and angiogenesis, thereby accelerating tissue repair. Notable challenges such as rapid gelation and uncontrolled calcium release are being addressed through advanced engineering strategies like multi-modal crosslinking and controlled ion-release systems. CaCl2-crosslinked hydrogels offer a dual benefit of rapid hemostasis and enhanced wound healing, positioning them as valuable tools in wound care. Addressing current challenges through interdisciplinary research and clinical validation will maximize their therapeutic potential and that may contribute to improved standards in regenerative medicine.
In vitro testing is a fundamental approach for advancing spinal biomechanics research. However, existing loading methods still exhibit notable limitations in physiological realism and motion controllability. This study introduces a spinal loading method that integrates robotic admittance control with dynamic movement primitives (DMPs) to enable motion loading of multi-segment spines, and provides a preliminary assessment of its reliability. A robotic testing system was developed, comprising a six-degree-of-freedom robotic arm integrated with a six-axis force sensor. Spinal traction trajectories were acquired with reference to anatomical planes, modeled, and subsequently reproduced using DMPs. The reconstructed trajectories were compared with the reference data to assess reproduction accuracy. The proposed method was further validated on ovine thoracolumbar specimens (T12-L3) under flexion-extension and lateral bending motions, and the measured ranges of motion (ROM) were compared with values reported in previous studies. A spinal loading method based on robotic admittance control combined with DMPs was successfully established. The experimental results demonstrated that the mean error between the demonstrated and reproduced trajectories was less than 2.5 mm, and the measured range of motion showed no significant difference compared with previously reported data (P < 0.05). The proposed method accurately reproduces physiological spinal motion characteristics, demonstrating its feasibility and validity for in vitro studies of three-dimensional spinal biomechanics.
While functional data analysis facilitates extensive interpretation of movement patterns, there are limited studies utilizing functional data analysis to examine running biomechanics in individuals post-ACLR. The current study aimed to determine altered running biomechanics in individuals with unilateral ACLR compared to the contralateral limb and matched control limbs. Twenty ACLR patients (time post-ACLR: 14.6 ± 6.1 months) and 20 matched controls participated in the study. All participants ran for 30 min at a self-selected speed (minimum 2.68 m/s) on an instrumented tandem treadmill. Frontal and sagittal lower extremity kinematics were calculated, and functional analysis of variance was used to compare the ACLR and contralateral limbs and the ACLR and control limbs. Relative to the control limbs, the ACLR limbs showed decreased knee flexion and ankle dorsiflexion angles from initial contact to approximately 90% of stance phase. Compared to the contralateral limbs, the ACLR limbs also demonstrated decreased 1.7° knee flexion and 1.2° ankle dorsiflexion angle in the mid-stance phase during running. Compared with the contralateral limbs and control limbs, the ACLR limbs demonstrated reduced joint excursions with decreased knee and hip flexion angles and ankle dorsiflexion angle. Future work may seek to determine whether these changes during running are associated with OA-related joint tissue changes.
Plantar fasciopathy (PF) results in decreased foot-muscle function and balance. The purpose was to investigate effects of performing exercises and wearing minimalist shoes on foot-muscle function and single-leg balance, compared to exercise-only in individuals with PF. Participants were randomly allocated into the Foot Rehabilitation and Minimalist ShoES (FRAMES)-group or control-group. Both groups performed exercises for 8 weeks; the FRAMES-group wore minimalist shoes. Outcome measures were collected at baseline and 8-weeks. Foot-muscle strength was assessed with a handheld-dynamometer and pulling-dynamometer for the great- and lesser-toes separately, for both limbs. Resting and resisted muscle-thickness and cross-sectional area (CSA) were assessed with ultrasound in a weight-bearing position for abductor hallucis, flexor hallucis brevis, flexor digitorum brevis, and quadratus plantae. Single-leg-balance (eyes open and closed) assessed on a force plate indicated center of pressure distance, 95% ellipse area, average x and y deviations, and maximum velocity in all 4 directions. Repeated Measures Analysis of Variance tests assessed changes by time and group. 34 participants completed the intervention (FRAMES: n = 18 (13 female), Control: n = 16 (11 female)). All participants experienced significant increases in handheld-dynamometer great- and lesser-toes strength in both limbs (p < 0.001), pulling-dynamometer great-toe strength for non-PF (p = 0.035) and PF (p = 0.010) limbs, and quadratus plantae-CSA-resisted (p = 0.004). There was a significant interaction for flexor digitorum brevis-CSA-resisted (p = 0.009), with a significant decrease in the control-group; and no single-leg-balance changes. Individuals with PF who perform exercises with or without minimalist shoes for 8 weeks can significantly increase foot-muscle strength, but not foot-muscle size or balance. The study was registered on ClinicalTrials.gov as "Effects of Foot Rehabilitation And Minimalist Shoes on Pain, Strength, and Function in Adults With Plantar Fasciopathy (FRAMES)", (ID: NCT06106958).
Hip-fracture gait recovery is multidomain, yet rehabilitation studies often rely on gait speed alone. The movement-specific hip mobility and kinematic changes accompanying early speed gains remain unclear. This study aimed to determine whether recovery of affected-side hip flexion passive range of motion (PROM) and sagittal-plane hip excursion is associated with gait-speed gain during early inpatient rehabilitation. This pilot prospective biomechanical analysis used participant-level data from a pre-post study following hip-fracture surgery. Sixteen participants completed paired assessments immediately before and after a 10-session early rehabilitation phase that included lower-body positive pressure walking. The primary outcome was change in gait velocity. Prespecified primary explanatory variables were changes in affected-side hip flexion PROM and sagittal-plane hip excursion. Associations were evaluated using Spearman correlation and covariate-adjusted linear models. Gait velocity increased from 0.48 ± 0.15 to 0.57 ± 0.19 m/s (mean change 0.094 m/s; p = 0.019). Affected-side hip flexion PROM improved by 21.9 ± 16.2 degrees (p < 0.001). Gait-speed change correlated with changes in affected-side hip flexion PROM (rho = 0.58, p = 0.018) and sagittal-plane hip excursion (rho = 0.51, p = 0.042). In adjusted models, a 10-degree increase in hip flexion PROM was associated with 0.042 m/s greater gait-speed gain (p = 0.047), and a 5-degree increase in sagittal-plane hip excursion with 0.046 m/s greater gain (p = 0.021). Early restoration of affected-side hip flexion PROM and sagittal-plane hip excursion is a clinically interpretable biomechanical correlate of walking-speed recovery after hip fracture. This movement-specific signal supports a range-of-motion-to-kinematics-to-speed pathway warranting testing in larger studies.
Post-Stroke Dysphagia (PSD) is a common complication after stroke. An efficient, noninvasive assessment method is especially crucial for dysphagia. Submental ultrasound is an emerging noninvasive method for evaluating swallowing, enabling dynamic, real-time monitoring of the movements of the tongue and hyoid bone methods. This was a cross-sectional, single-center, observational study involving 213 stroke patients admitted to the department of rehabilitation between June 2023 and June 2024. All patients underwent assessment using the Penetration-Aspiration Scale (PAS) via videofluoroscopic swallowing study or flexible endoscopic evaluation of swallowing. All patients' tongue-hyoid bone movement parameters, such as hyoid bone displacement, hyoid bone displacement/resting distance ratio, geniohyoid muscle movement speed, and tongue muscle movement speed, were measured by submental ultrasound. The Aspiration and Penetration group had smaller hyoid bone displacement and slower geniohyoid and tongue muscle movement. All of these differences were statistically significant (P < 0.001). The predictive model for assessing the risk of severe-PSD (PAS 6-8 grade) achieved an area under the receiver operating characteristic curve of 0.927 (95% CI: 0.886-0.967). All tongue-hyoid bone movement parameters showed negative correlations with PAS grading when PAS was used as a continuous variable. Parameters related to hyoid bone movement and geniohyoid muscle velocity serve as key indicators of PSD severity. Submental ultrasound measurement of tongue-hyoid motion parameters demonstrates excellent assessment and predictive value for PSD severity, warranting clinical implementation.
Multiple sclerosis is a chronic neurodegenerative disease that often compromises gait, a key determinant of independence and quality of life. Nonlinear gait analysis may provide useful information about motor control alterations in people with multiple sclerosis, yet current evidence remains limited and fragmented. This systematic review synthesized research on nonlinear gait variables in this population, focusing on entropy, Lyapunov exponents, and detrended fluctuation analysis. This systematic review followed PRISMA guidelines and included studies retrieved from PubMed and Web of Science. Eligible studies compared people with multiple sclerosis and healthy controls during treadmill or overground walking tests and reported nonlinear gait variability outcomes. Methodological quality was assessed using the JBI Checklist. From 99 records initially identified, 10 studies met the inclusion criteria, comprising 430 patients and 212 healthy controls. Most studies examined the Lyapunov exponent; five of nine studies reported significant between-group differences, although only three showed higher values in people with multiple sclerosis. Fewer studies assessed entropy or detrended fluctuation analysis, and significant differences were less consistent. Nonlinear gait metrics, particularly the Lyapunov exponent, may provide useful information about altered gait dynamics in people with multiple sclerosis, including minimally disabled patients. These metrics may be influenced by fatigue, motor control alterations, and methodological choices, although current evidence remains limited and heterogeneous. Future studies using transparent, pre-specified, and harmonised reporting approaches are needed to clarify their role in research and clinical contexts.