Metformin-Associated Vitamin B12 Deficiency: An Underrecognized Complication.

Metformin-associated vitamin B12 deficiency is a well-established side effect, especially in patients taking higher doses of metformin or who have existing risk factors. Severe deficiency causes a wide range of systemic disorders. Gait instability, which leads to frequent falling, is usually an underrecognized side effect. Older patients are more likely to develop chronic subdural hematoma even with minor trauma. We present a case of 84-year-old man with type 2 diabetes mellitus with acute-on-chronic subdural hematoma from frequent falls. Metformin therapy at dose of 1700 mg/day was given for more than 25 years. He had been in his usual state of health until 10 months ago when he began to have frequent fallings and fatigue. Physical examination in this admission revealed new-onset impaired vibratory sensation and proprioception in both feet and positive Romberg test. Subsequent evaluations demonstrated undetectable plasma vitamin B12 level and elevated plasma homocysteine. Improvement in neurological symptoms occurred within 1 week of vitamin B12 replacement and surgical hematoma evacuation. This case highlights the importance of awareness and periodic monitoring of vitamin B12 status among older patients taking metformin.

Classification performance of sEMG and kinematic parameters for distinguishing between non-lame and induced lameness conditions in horses.

Despite its proven research applications, it remains unknown whether surface electromyography (sEMG) can be used clinically to discriminate non-lame from lame conditions in horses. This study compared the classification performance of sEMG absolute value (sEMGabs) and asymmetry (sEMGasym) parameters, alongside validated kinematic upper-body asymmetry parameters, for distinguishing non-lame from induced fore- (iFL) and hindlimb (iHL) lameness. Bilateral sEMG and 3D-kinematic data were collected from clinically non-lame horses (n = 8) during in-hand trot. iFL and iHL (2-3/5 AAEP) were induced on separate days using a modified horseshoe, with baseline data initially collected each day. sEMG signals were DC-offset removed, high-pass filtered (40 Hz), and full-wave rectified. Normalized, average rectified value (ARV) was calculated for each muscle and stride (sEMGabs), with the difference between right and left-side ARV representing sEMGasym. Asymmetry parameters (MinDiff, MaxDiff, Hip Hike) were calculated from poll, withers, and pelvis vertical displacement. Receiver-operating-characteristic (ROC) and area under the curve (AUC) analysis determined the accuracy of each parameter for distinguishing baseline from iFL or iHL. Both sEMG parameters performed better for detecting iHL (0.97 ≥ AUC ≥ 0.48) compared to iFL (0.77 ≥ AUC ≥ 0.49). sEMGabs performed better (0.97 ≥ AUC ≥ 0.49) than sEMGasym (0.76 ≥ AUC ≥ 0.48) for detecting both iFL and iHL. Like previous studies, MinDiff Poll and Pelvis asymmetry parameters (MinDiff, MaxDiff, Hip Hike) demonstrated excellent discrimination for iFL and iHL, respectively (AUC > 0.95). Findings support future development of multivariate lameness-detection approaches that combine kinematics and sEMG. This may provide a more comprehensive approach to diagnosis, treatment, and monitoring of equine lameness, by measuring the underlying functional cause(s) at a neuromuscular level.

The effect of electromyographic feedback functional electrical stimulation on the plantar pressure in stroke patients with foot drop.

Purpose: The purpose of this study was to observe, using Footscan analysis, the effect of electromyographic feedback functional electrical stimulation (FES) on the changes in the plantar pressure of drop foot patients. Methods: This case-control study enrolled 34 stroke patients with foot drop. There were 17 cases received FES for 20 min per day, 5 days per week for 4 weeks (the FES group) and the other 17 cases only received basic rehabilitations (the control group). Before and after 4 weeks, the walking speed, spatiotemporal parameters and plantar pressure were measured. Results: After 4 weeks treatments, Both the FES and control groups had increased walking speed and single stance phase percentage, decreased step length symmetry index (SI), double stance phase percentage and start time of the heel after 4 weeks (p < 0.05). The increase in walking speed and decrease in step length SI in the FES group were more significant than the control group after 4 weeks (p < 0.05). The FES group had an increased initial contact phase, decreased SI of the maximal force (Max F) and impulse in the medial heel after 4 weeks (p < 0.05). Conclusion: The advantages of FES were: the improvement of gait speed, step length SI, and the enhancement of propulsion force were more significant. The initial contact phase was closer to the normal range, which implies that the control of ankle dorsiflexion was improved. The plantar dynamic parameters between the two sides of the foot were more balanced than the control group. FES is more effective than basic rehabilitations for stroke patients with foot drop based on current spatiotemporal parameters and plantar pressure results.

Analysis of gait pattern related to high cerebral small vessel disease burden using quantitative gait data from wearable sensors.

BACKGROUND AND OBJECTIVES: Sensor-based wearable devices help to obtain a wide range of quantitative gait parameters, which provides sufficient data to investigate disease-specific gait patterns. Although cerebral small vessel disease (CSVD) plays a significant role in gait impairment, the specific gait pattern associated with a high burden of CSVD remains to be explored. METHODS: We analyzed the gait pattern related to high CSVD burden from 720 participants (aged 55-65 years, 42.5 % male) free of neurological disease in the Taizhou Imaging Study. All participants underwent detailed quantitative gait assessments (obtained from an insole-like wearable gait tracking device) and brain magnetic resonance imaging examinations. Thirty-three gait parameters were summarized into five gait domains. Sparse sliced inverse regression was developed to extract the gait pattern related to high CSVD burden. RESULTS: The specific gait pattern derived from several gait domains (i.e., angles, phases, variability, and spatio-temporal) was significantly associated with the CSVD burden (OR=1.250, 95 % CI: 1.011-1.546). The gait pattern indicates that people with a high CSVD burden were prone to have smaller gait angles, more stance time, more double support time, larger gait variability, and slower gait velocity. Furthermore, people with this gait pattern had a 25 % higher risk of a high CSVD burden. CONCLUSIONS: We established a more stable and disease-specific quantitative gait pattern related to high CSVD burden, which is prone to facilitate the identification of individuals with high CSVD burden among the community residents or the general population.

The effect of amplitude normalization technique, walking speed, and reporting metric on whole-body angular momentum and its interpretation during normal gait.

Whole-body angular momentum (WBAM) represents the cancellations of angular momenta that are produced during a reciprocal gait pattern. WBAM is sensitive to small changes and is used to compare dynamic gait patterns under different walking conditions. Study designs and the normalization techniques used to define WBAM vary and make comparisons between studies difficult. To address this problem, WBAM about each anatomical axis of rotation from a healthy control population during normal gait were investigated within four metrics: 1) range of WBAM, 2) integrated WBAM, 3) statistical parametric mapping (SPM), and 4) principal component analysis (PCA). These data were studied as a function of walking speed and normalization. Normalization techniques included: 1) no normalization, 2) normalization by height, body mass and walking speed, and 3) normalization by height, body mass and a scalar number, gravity×height, that is independent of walking velocity. Significant results were obtained as a function of walking speed regardless of normalization technique. However, the interpretation of significance within each metric was dependent on the normalization technique. Method 3 was the most robust technique as the differences were not altered from the expected relationships within the raw data. Method 2 actually inverted the expected relationship in WBAM amplitude as a function of walking speed, which skewed the results and their interpretation. Overall, SPM and PCA statistical methods provided better insights into differences that may be important. However, depending on the normalization technique used, caution is advised when interpreting significant findings when comparing participants with disparate walking speeds.

Multi-segment foot kinematics during gait in children with spastic cerebral palsy.

BACKGROUND: Foot deformities (e.g. planovalgus and cavovarus) are very common in children with spastic cerebral palsy (CP), with the midfoot often being involved. Dynamic foot function can be assessed with 3D gait analysis including a multi-segment foot model. Incorporating a midfoot segment in such a model, allows quantification of separate Chopart and Lisfranc joint kinematics. Yet, midfoot kinematics have not previously been reported in CP. RESEARCH QUESTIONS: What is the difference in multi-segment kinematics including midfoot joints between common foot deformities in CP and typically-developing feet? METHODS: 103 feet of 57 children with spastic CP and related conditions were retrospectively included and compared with 15 typically-developing children. All children underwent clinical gait analysis with the Amsterdam Foot Model marker set. Multi-segment foot kinematics were calculated for three strides per foot and averaged. A k-means cluster analysis was performed to identify foot deformity groups that were present within CP data. The deformity type represented by each cluster was based on the foot posture index. Kinematic output of the clusters was compared to typically-developing data for a static standing trial and for the range of motion and kinematic waveforms during walking, using regular and SPM independent t-tests respectively. RESULTS: A neutral, planovalgus and varus cluster were identified. Neutral feet showed mostly similar kinematics as typically-developing data. Planovalgus feet showed increased ankle valgus and Chopart dorsiflexion, eversion and abduction. Varus feet showed increased ankle varus and Chopart inversion and adduction. SIGNIFICANCE: This study is the first to describe Chopart and Lisfranc joint kinematics in different foot deformities of children with CP. It shows that adding a midfoot segment can provide additional clinical and kinematic information. It highlights joint angles that are more distinctive between deformities, which could be helpful to optimize the use of multi-segment foot kinematics in the clinical decision making process.

Fourier Analysis of the Vertical Ground Reaction Force During Walking: Applications for Quantifying Differences in Gait Strategies.

Time series biomechanical data inform our understanding of normal gait mechanics and pathomechanics. This study examines the utility of different quantitative methods to distinguish vertical ground reaction forces (VGRFs) from experimentally distinct gait strategies. The goals of this study are to compare measures of VGRF data-using the shape factor method and a Fourier series-based analysis-to (1) describe how these methods reflect and distinguish gait patterns and (2) determine which Fourier series coefficients discriminate normal walking, with a relatively stiff-legged gait, from compliant walking, using deep knee flexion and limited vertical oscillation. This study includes a reanalysis of previously presented VGRF data. We applied the shape factor method and fit 3- to 8-term Fourier series to zero-padded VGRF data. We compared VGRF renderings using Euclidean L2 distances and correlations stratified by gait strategy. Euclidean L2 distances improved with additional harmonics, with limited improvement after the seventh term. Euclidean L2 distances were greater in shape factor versus Fourier series renderings. In the 8 harmonic model, amplitudes of 9 Fourier coefficients-which contribute to VGRF features including peak and local minimum amplitudes and limb loading rates-were different between normal and compliant walking. The results suggest that Fourier series-based methods distinguish between gait strategies.

Spinocerebellar ataxia 27B (SCA27B), a frequent late-onset cerebellar ataxia.

Genetic cerebellar ataxias are still a diagnostic challenge, and yet not all of them have been identified. Very recently, in early 2023, a new cause of late-onset cerebellar ataxia (LOCA) was identified, spinocerebellar ataxia 27B (SCA27B). This is an autosomal dominant ataxia due to a GAA expansion in intron 1 of the FGF14 gene. Thanks to the many studies carried out since its discovery, it is now possible to define the clinical phenotype, its particularities, and the progression of SCA27B. It has also been established that it is one of the most frequent causes of LOCA. The core phenotype of the disease consists of slowly progressive late-onset ataxia with cerebellar syndrome, oculomotor disorders including downbeat nystagmus, and episodic symptoms such as diplopia. Therapeutic approaches have been proposed, including acetazolamide, and 4-aminopyridine, the latter with a better benefit/tolerance profile.

3D Kinematics Quantifies Gait Response to Levodopa earlier and to a more Comprehensive Extent than the MDS-Unified Parkinson's Disease Rating Scale in Patients with Motor Complications.

BACKGROUND: Quantitative 3D movement analysis using inertial measurement units (IMUs) allows for a more detailed characterization of motor patterns than clinical assessment alone. It is essential to discriminate between gait features that are responsive or unresponsive to current therapies to better understand the underlying pathophysiological basis and identify potential therapeutic strategies. OBJECTIVES: This study aims to characterize the responsiveness and temporal evolution of different gait subcomponents in Parkinson's disease (PD) patients in their OFF and various ON states following levodopa administration, utilizing both wearable sensors and the gold-standard MDS-UPDRS motor part III. METHODS: Seventeen PD patients were assessed while wearing a full-body set of 15 IMUs in their OFF state and at 20-minute intervals following the administration of a supra-threshold levodopa dose. Gait was reconstructed using a biomechanical model of the human body to quantify how each feature was modulated. Comparisons with non-PD control subjects were conducted in parallel. RESULTS: Significant motor changes were observed in both the upper and lower limbs according to the MDS-UPDRS III, 40 minutes after levodopa intake. IMU-assisted 3D kinematics detected significant motor alterations as early as 20 minutes after levodopa administration, particularly in upper limbs metrics. Although all "pace-domain" gait features showed significant improvement in the Best-ON state, most rhythmicity, asymmetry, and variability features did not. CONCLUSION: IMUs are capable of detecting motor alterations earlier and in a more comprehensive manner than the MDS-UPDRS III. The upper limbs respond more rapidly to levodopa, possibly reflecting distinct thresholds to levodopa across striatal regions.

Enhancing gait cadence through rhythm-modulated music: A study on healthy adults.

BACKGROUND AND OBJECTIVE: Gait disorders stemming from brain lesions or chemical imbalances, pose significant challenges for patients. Proposed treatments encompass medication, deep brain stimulation, physiotherapy, and visual stimulation. Music, with its harmonious structures, serves as a continuous reference, synchronizing muscle activities through neural connections between hearing and motor functions, can show promise in gait disorder management. This study explores the influence of heightened music rhythm on young healthy participants' gait cadence in three conditions: FeedForward (independent rhythm), FeedBack (cadence-synced rhythm), and Adaptive (cadence-controlled musical experience). The objective is to increase gait cadence through rhythm modulation during walking. METHOD: The study involved 18 young healthy participants (13 males and 5 females) who did not have any gait or hearing disorders. Each participant completed the gait task in the three aforementioned conditions. Each condition was comprised of three sessions: 1) Baseline, where participants walked while listening to the original music; 2) Intervention, changing the music rhythm to affect the gait cadence; and 3) Realign, replaying the original music and measuring the durability of the effect of the Intervention session. The measurement tool was a pair of footwear equipped with push-button switches that transmited the foot-to-ground contact to the LabVIEW® software, all designed by the research team. Repeated measures of ANOVA was employed to evaluate the impact of the sessions and conditions. RESULTS: In all three conditions, there was a significant effect of music on increasing gait cadence during Intervention and Realign sessions (p < 0.001). Additionally, the immediate impact of music on gait cadence in the Adaptive condition was superior to the other conditions. CONCLUSION: The study findings indicate that increasing the rhythm of music during walking has a significant impact on gait cadence among young healthy participants. This effect remained significant even after realigning the music to normal. It could be harnessed to support the rehabilitation of individuals with movement disorders characterized by a decrease in movement speed, such as Parkinson's disease. Moreover, the results indicate that the Adaptive method showed promising outcomes, suggesting its potential for further exploration as an effective means to control gait cadence.

Is spinopelvic compensation associated with unstable gait?: Analysis using whole spine X-rays and a two-point accelerometer during gait in healthy adults.

BACKGROUND: Pelvic incidence (PI)-lumbar lordosis (LL) mismatch has a significant destabilizing effect on the center of gravity sway in the static standing position. However, the association between spinopelvic alignment and balance during gait in healthy volunteers is poorly understood. RESEARCH QUESTION: The degree of PI-LL mismatch and trunk anterior tilt in the static standing posture influences dynamic balance during gait. METHODS: In this study, 131 healthy volunteers were divided into two groups: harmonious group (PI - LL ≤ 10°; n = 91) and unharmonious group (PI - LL > 10°; n = 40). A two-point accelerometer system was used for gait analysis; accelerometers were attached to the pelvis and upper trunk to measure acceleration in the forward-backward, right-left, and vertical directions so that sagittal (front-back) deviation width, coronal (right-left) width, and vertical width and their ratios were calculated. Measurements were compared between the two groups, and correlations between alignment and accelerometer data were examined. RESULTS: The harmonious group showed a negative correlation between pelvic sagittal width and PI - LL, pelvic tilt (PT), and sagittal vertical axis (SVA) (correlation coefficient ρ = -0.42, -0.38, and -0.4, respectively), and a positive correlation between sagittal ratio and PI - LL (ρ = 0.35). The unharmonious group showed a positive correlation between pelvic sagittal width and PI and PT (ρ = 0.43 and 0.33, respectively) and between sagittal ratio and SVA (ρ = 0.32). The unharmonious group showed a positive correlation between upper trunk sagittal width and PI - LL and PT (ρ = 0.38 and 0.36, respectively). SIGNIFICANCE: The association between spinal alignment and gait parameters differs depending on the presence or absence of PI-LL mismatch. The degree of pelvic compensation and trunk anterior tilt during static standing were associated with unstable gait balance.

Comparability between wearable inertial sensors and an electronic walkway for spatiotemporal and relative phase data in young children aged 6-11 years.

BACKGROUND: Approaches to gait analysis are evolving rapidly and now include a wide range of options: from e-patches to video platforms to wearable inertial measurement unit systems. Newer options for gait analysis are generally more inclusive for the assessment of children, more cost effective and easier to administer. However, there is limited data on the comparability of newer systems with more established traditional approaches in young children. RESEARCH QUESTION: To determine comparability between the Physilog®5 wearable inertial sensor and GAITRite® electronic walkway for spatiotemporal (stride length, time and velocity, cadence) and relative phase (double support time, stance, swing, loading, foot flat and push off) data in young children. METHODS: A total 34 typically developing participants (41% female) aged 6-11 years old median age 8.99 years old (interquartile range 2.83) were assessed walking at self-selected speed over the GAITRite® electronic walkway while concurrently wearing shoe-attached Physilog®5 IMU sensors. Level of agreement was analysed by Lin's concordance correlation coefficient (CCC), Bland-Altman plots and 95% limit of agreement. Systematic bias was assessed using 95% confidence interval of the mean difference. RESULTS: Excellent to almost perfect agreement was observed between systems for spatiotemporal metrics: cadence (CCC=0.996), stride length (CCC=0.993), stride time (CCC=0.996), stride velocity (CCC=0.988). The relative phase metrics adjusted for stride velocity showed improved comparability when compared to the unadjusted metrics: swing adjusted (adj) (CCC=0.635); stance adj (CCC: 0.879); loading adj: (CCC=0.626). SIGNIFICANCE: Spatiotemporal metrics are highly compatible across GAITRite® electronic walkway and Physilog®5 IMU systems in young children. Relative phase metrics were somewhat compatible between systems when adjusted for stride velocity.

Robotic assisted and exoskeleton gait training effect in mental health and fatigue of multiple sclerosis patients. A systematic review and a meta-analysis.

PURPOSE: Robotic and Exoskeleton Assisted Gait Training (REAGT) has become the mainstream gait training module. Studies are investigating the psychosocial effects of REAGT mostly as secondary outcomes. Our systematic review and meta-analysis aims to investigate the effects of REAGT in MS patients' mental health and fatigue. MATERIALS AND METHODS: We searched the electronic databases (Scopus, PubMed, Pedro, Cochrane Trials, Dare) for RCT studies fulfilling our inclusion criteria. A meta-analysis of available assessment tools was conducted calculating the summary mean differences in two different timepoints, before and after the intervention using random-effects models. RESULTS: The systematic search of the electronic databases identified 302 studies. Seven RCT studies were considered eligible for data extraction and meta-analysis, according to our eligibility criteria. We were able to obtain adequate data to proceed with a quantitative synthesis for QoL SF36-MC (Mental Component), QoL SF-36 mental and psychosocial subscales, Multiple Sclerosis Quality of Life-54-Mental Health Composite (MSQoL-54-MHC), Patient's Health Questionnaire (PHQ-9) and Fatigue Severity Scale (FSS). CONCLUSIONS: Overall, REAGT seems to have a positive effect to Quality of Life, especially in MS patients' perspective of General and Mental Health and a slight positive effect in depression as measured by PHQ-9.Implications for rehabilitationMultiple Sclerosis (MS) decreases physical and non-physical aspects of patients' quality of life perspective.Rehabilitation strategy must take into consideration the non-physical effects of a training intervention.Robotic and Exoskeleton Gait Training has a positive effect in MS patients' non-physical quality of life and a slight positive effect in depression.

Gait Analysis of Knee Joint Walking Based on Image Processing.

BACKGROUND: With the in-depth development of assistive treatment devices, the application of artificial knee joints in the rehabilitation of amputees is becoming increasingly mature. The length of residual limbs and muscle strength of patients have individual differences, and the current artificial knee joint lacks certain adaptability in the personalized rehabilitation of patients. PURPOSE: In order to deeply analyze the impact of different types of artificial knee joints on the walking function of unilateral thigh amputees, improve the performance of artificial knee joints, and enhance the rehabilitation effect of patients, this article combines image processing technology to conduct in-depth research on the walking gait analysis of different artificial knee joints of unilateral thigh amputees. METHODS: This article divides patients into two groups: the experimental group consists of patients with single leg amputation, and the control group consists of patients with different prostheses. An image processing system is constructed using universal video and computer hardware, and relevant technologies are used to recognize and track landmarks; Furthermore, image processing technology was used to analyze the gait of different groups of patients. Finally, by analyzing the different psychological reactions of amputees, corresponding treatment plans were developed. RESULTS: Different prostheses worn by amputees have brought varying degrees of convenience to life to a certain extent. The walking stability of wearing hydraulic single axis prosthetic joints is only 79%, and the gait elegance is relatively low. The walking stability of wearing intelligent artificial joints is as high as 96%. Elegant gait is basically in good condition. CONCLUSION: Image processing technology helps doctors and rehabilitation practitioners better understand the gait characteristics and rehabilitation progress of patients wearing different artificial knee joints, providing objective basis for personalized rehabilitation of patients.

Ankle Muscle Strength and Gait Function After Dorsal Closing Wedge Calcaneal Osteotomy for Haglund Exostosis-Related Heel Pain.

BACKGROUND: Haglund exostosis-related heel pain may be surgically treated with dorsal closing wedge calcaneal osteotomy (DCWCO). Recent reports on this technique show good clinical and self-reported outcomes. However, uncertainty about functional consequences related to ankle muscle strength and gait function due to a shortened Achilles tendon lever arm exists. METHODS: Fifteen patients (15 feet) with Haglund exostosis-related heel pain were surgically treated with DCWCO and evaluated before and 1 year after surgery. Isometric plantar flexion and dorsiflexion strength was quantified for both the involved and the uninvolved limb. Gait analysis was performed at a self-selected walking speed using a 3D motion capture system including force plates. Self-reported outcomes (Foot Function Index and Global Treatment Outcome) were also assessed. RESULTS: Before surgery, as well as after surgery, plantar flexion strength of the involved limb was significantly lower compared to the uninvolved limb while dorsiflexion strength did not differ between limbs at both time points. Step length and time, ankle flexion angles, power generation, and propulsive impulses during gait did not differ between limbs both before and after surgery. Propulsive impulse and step length of the involved limb increased from pre- to postsurgery with an effect size of 1.04 and 0.48, respectively, revealing a general improvement in gait dynamics. Total Foot Function Index improved by 48% after surgery, and 80% of patients rated their surgery as "helped" or "helped a lot" (Global Treatment Outcome). CONCLUSION: In this relatively small cohort, we found that patients treated for Haglund exostosis-related heel pain with DCWCO surgery had minor interlimb differences in gait kinematics and kinetics and generally improved gait dynamics and self-reported function at 1-year follow-up. LEVEL OF EVIDENCE: Level II, observational prospective cohort study.

Is dynamic motor control clinically important for identifying gait deviations in individuals with cerebral palsy?

INTRODUCTION: Individuals with cerebral palsy (CP) often present with altered motor control. This can be assessed selectively during sitting/lying with the Selective Control Assessment of the Lower Extremity (SCALE), or dynamically with the dynamic motor control index during walking (walk-DMC). Both approaches suggest that altered selective motor control relate to larger gait deviations. RESEARCH QUESTION: Does the walk-DMC provide valuable information in addition to the SCALE for estimating gait deviations in individuals with CP. METHODS: Retrospective, treadmill-based gait analysis data of 157 children with spastic CP (mean 11.4±3.5 years) and Gross Motor Function Classification System levels I (n=45), II (n=88) or III (n=24) were extracted. Gait kinematic deviations were evaluated using the Gait Profile Score (GPS). The SCALE, walk-DMC and GPS were extracted for the more clinically involved leg (unilateral-analysis), and for both legs together (bilateral-analysis). RESULTS: GPS moderately correlated with both SCALE and walk-DMC scores, unilaterally and bilaterally (r≥0.4; p<0.001). Multivariate linear regression analyses were conducted, taking into account potential confounding factors. In the unilateral analysis, 54% of the GPS variance was explained (p<0.001), with both walk-DMC and SCALE significantly contributing to the GPS variance (p=0.006 and p=0.008, respectively). In the bilateral analysis, 61% of the GPS variance was explained (p<0.001), with both walk-DMC and SCALE significantly contributing to the GPS variance (p=0.006 and p<0.001, respectively). Dimensionless walking speed and use of assistive devices were the only confounding factors included in each analysis. SIGNIFICANCE: Both SCALE and walk-DMC significantly contribute to GPS variance, suggesting that they likely measure different components of motor control, and both may be useful in understanding the underlying relationship between motor control and deviations in gait kinematics.

Effects of tendon elongation on plantar pressure and clinical outcomes: A comparative analysis between open repair and minimally invasive surgery.

PURPOSE: The aim of this study was to assess whether variances in Achilles tendon elongation are linked to dissimilarities in the plantar pressure distribution following two different surgical approaches for an Achilles tendon rupture (ATR). METHODS: All patients who were treated with open or minimally invasive surgical repair (MIS) and were over 2 years post their ATR were eligible for inclusion. A total of 65 patients with an average age of 43 ± 11 years were included in the study. Thirty-five patients were treated with open repair, and 30 patients were treated with MIS. Clinical outcomes were evaluated using the American Orthopedic Foot and Ankle Society (AOFAS) and ATR Score (ATRS). Achilles tendon elongation was measured using axial and sagittal magnetic resonance imaging scans. Plantar pressure measurements for the forefoot, midfoot and hindfoot during gait were divided into percentages based on total pressure, measured in g/cm2 for each area. RESULTS: The average AOFAS score was found 'excellent' (93 ± 2.8) in the MIS group, while it was found 'good' (87.4 ± 5.6) in the open repair group. In addition, the MIS group showed significantly superior ATRS scores (78.8 ± 7.4) compared to the open repair group (56.4 ± 15.4) (p < 0.001). The average tendon elongation in the MIS group was 11.3 ± 2 mm, while it was 17.3 ± 4.3 mm (p < 0.001) in the open repair group. While the open repair group showed significantly higher plantar pressure distribution in the initial contact and preswing phases compared to uninjured extremities, there was no significant difference between the uninjured extremities and the MIS group. CONCLUSION: In conclusion, the findings of this study demonstrated that minimally invasive surgery was associated with less tendon elongation, more proximity to the plantar pressure distributions of the uninjured extremity and superior clinical outcomes compared to open surgical repair. Therefore, minimally invasive surgery may be considered a more suitable option for acute Achilles tendon repair to achieve overall better outcomes. LEVEL OF EVIDENCE: Level III.

Bidirectional mediation of bone mineral density and brain atrophy on their associations with gait variability.

This mediation analysis aimed to investigate the associations among areal bone mineral density, mobility-related brain atrophy, and specific gait patterns. A total of 595 participants from the Taizhou Imaging Study, who underwent both gait and bone mineral density measurements, were included in this cross-sectional analysis. We used a wearable gait tracking device to collect quantitative gait parameters and then summarized them into independent gait domains with factor analysis. Bone mineral density was measured in the lumbar spine, femoral neck, and total hip using dual-energy X-ray absorptiometry. Magnetic resonance images were obtained on a 3.0-Tesla scanner, and the volumes of brain regions related to mobility were computed using FreeSurfer. Lower bone mineral density was found to be associated with higher gait variability, especially at the site of the lumbar spine (ß = 0.174, FDR = 0.001). Besides, higher gait variability was correlated with mobility-related brain atrophy, like the primary motor cortex (ß = 0.147, FDR = 0.006), sensorimotor cortex (ß = 0.153, FDR = 0.006), and entorhinal cortex (ß = 0.106, FDR = 0.043). Bidirectional mediation analysis revealed that regional brain atrophy contributed to higher gait variability through the low lumbar spine bone mineral density (for the primary motor cortex, P = 0.018; for the sensorimotor cortex, P = 0.010) and the low lumbar spine bone mineral density contributed to higher gait variability through the primary motor and sensorimotor cortices (P = 0.026 and 0.010, respectively).

Phenotypic analysis of ataxia in spinocerebellar ataxia type 6 mice using DeepLabCut.

This study emphasizes the benefits of open-source software such as DeepLabCut (DLC) and R to automate, customize and enhance data analysis of motor behavior. We recorded 2 different spinocerebellar ataxia type 6 mouse models while performing the classic beamwalk test, tracked multiple body parts using the markerless pose-estimation software DLC and analyzed the tracked data using self-written scripts in the programming language R. The beamwalk analysis script (BAS) counts and classifies minor and major hindpaw slips with an 83% accuracy compared to manual scoring. Nose, belly and tail positions relative to the beam, as well as the angle at the tail base relative to the nose and tail tip were determined to characterize motor deficits in greater detail. Our results found distinct ataxic abnormalities such as an increase in major left hindpaw slips and a lower belly and tail position in both SCA6 ataxic mouse models compared to control mice at 18 months of age. Furthermore, a more detailed analysis of various body parts relative to the beam revealed an overall lower body position in the SCA684Q compared to the CT-longQ27PC mouse line at 18 months of age, indicating a more severe ataxic deficit in the SCA684Q group.