Innovative Design and Development of Personalized Ankle-Foot Orthoses for Survivors of Stroke With Equinovarus Foot: Protocol for a Feasibility and Comparative Trial.

BACKGROUND: Ankle-foot orthoses (AFOs) are vital in gait rehabilitation for patients with stroke. However, many conventional AFO designs may not offer the required precision for optimized patient outcomes. With the advent of 3D scanning and printing technology, there is potential for more individualized AFO solutions, aiming to enhance the rehabilitative process. OBJECTIVE: This nonrandomized trial seeks to introduce and validate a novel system for AFO design tailored to patients with stroke. By leveraging the capabilities of 3D scanning and bespoke software solutions, the aim is to produce orthoses that might surpass conventional designs in terms of biomechanical effectiveness and patient satisfaction. METHODS: A distinctive 3D scanner, complemented by specialized software, will be developed to accurately capture the biomechanical data of leg movements during gait in patients with stroke. The acquired data will subsequently guide the creation of patient-specific AFO designs. These personalized orthoses will be provided to participants, and their efficacy will be compared with traditional AFO models. The qualitative dimensions of this experience will be evaluated using the Quebec User Evaluation of Satisfaction With Assistive Technology (QUEST) assessment tool. Feedback from health care professionals and the participants will be considered throughout the trial to ensure a rounded understanding of the system's implications. RESULTS: Spatial-temporal parameters will be statistically compared using paired t tests to determine significant differences between walking with the personalized orthosis, the existing orthosis, and barefoot conditions. Significant differences will be identified based on P values, with P<.05 indicating statistical significance. The Statistical Parametric Mapping method will be applied to graphically compare kinematic and kinetic data across the entire gait cycle. QUEST responses will undergo statistical analysis to evaluate patient satisfaction, with scores ranging from 1 (not satisfied) to 5 (very satisfied). Satisfaction scores will be presented as mean and SD values. Significant variations in satisfaction levels between the personalized and existing orthosis will be assessed using a Wilcoxon signed rank test. The anticipation is that the AFOs crafted through this innovative system will either match or outperform existing orthoses in use, with higher patient satisfaction rates. CONCLUSIONS: Embracing the synergy of technology and biomechanics may hold the key to revolutionizing orthotic design, with the potential to set new standards in patient-centered orthotic solutions. However, as with all innovations, a balanced approach, considering both the technological possibilities and individual patient needs, will be paramount to achieving optimal outcomes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/52365.

Effects of repeated sprinting on hamstring shear modulus pattern and knee flexor neuromuscular parameters.

The purpose of the present study was to examine the acute effects of a maximum repeated sprint protocol on (1) hamstring shear modulus and (2) knee flexor neuromuscular parameters such as peak torque (PT) and rate of torque development (RTD). Muscle shear modulus was assessed in 18 healthy males using shear wave elastography at rest and during 30° isometric knee flexion at 20% of maximal voluntary isometric contraction, before and after a 10 × 30 m repeated sprint protocol. There was a 9% decrease in average speed between the fastest and slowest sprint (p < 0.001; d = 2.27). A pre-post decrease was observed in PT (p = 0.004; η2p = 0.399) and in the 0-50 ms (p = 0.042; η2p = 0.222), and 50-100 ms (p = 0.028; η2p = 0.254) RTD periods. For the active shear modulus, the only significant change after the sprint task was in the biceps femoris long head (BFlh) with an increase of 10% (Pre: 26.29 ± 8.89 kPa; Post: 28.93 ± 8.31 kPa; p = 0.015; d = 0.31). The present study provides evidence that repeated sprinting leads to significant decreases in average speed, PT, early RTD (0-50 ms; 50-100 ms), and to an increase in BFlh active shear modulus without changing the shear modulus of the other hamstrings muscles.

Gait Analysis in Children with Cerebral Palsy: Are Plantar Pressure Insoles a Reliable Tool?

Cerebral palsy (CP) is a common cause of motor disability, and pedobarography is a useful, non-invasive, portable, and accessible tool; is easy to use in a clinical setting; and can provide plenty of information about foot-soil interaction and gait deviations. The reliability of this method in children with CP is lacking. The aim of this study is to investigate test-retest reliability and minimal detectable change (MDC) of plantar pressure insole variables in children with CP. Eight children performed two trials 8 ± 2.5 days apart, using foot insoles to collect plantar pressure data. Whole and segmented foot measurements were analyzed using intraclass correlation coefficients (ICC). The variability of the data was measured by calculating the standard error of measurement (SEM) and the MDC/ICC values demonstrated high test-retest reliability for most variables, ranging from good to excellent (ICC ≥ 0.60). The SEM and the MDC values were considered low for the different variables. The variability observed between sessions may be attributed to the heterogeneous sub-diagnosis of CP.

Effects of Ankle Foot Orthoses on the Gait Patterns in Children with Spastic Bilateral Cerebral Palsy: A Scoping Review.

BACKGROUND: Cerebral palsy (CP) is the most common cause of motor disability in children and can cause severe gait deviations. The sagittal gait patterns classification for children with bilateral CP is an important guideline for the planning of the rehabilitation process. Ankle foot orthoses should improve the biomechanical parameters of pathological gait in the sagittal plane. METHODS: A systematic search of the literature was conducted to identify randomized controlled trials (RCT) and controlled clinical trials (CCT) which measured the effect of ankle foot orthoses (AFO) on the gait of children with spastic bilateral CP, with kinetic, kinematic, and functional outcomes. Five databases (Pubmed, Scopus, ISI Web of SCIENCE, SciELO, and Cochrane Library) were searched before February 2020. The PEDro Score was used to assess the methodological quality of the selected studies and alignment with the Cochrane approach was also reviewed. Prospero registration number: CRD42018102670. RESULTS: We included 10 studies considering a total of 285 children with spastic bilateral CP. None of the studies had a PEDro score below 4/10, including five RCTs. We identified five different types of AFO (solid; dynamic; hinged; ground reaction; posterior leaf spring) used across all studies. Only two studies referred to a classification for gait patterns. Across the different outcomes, significant differences were found in walking speed, stride length and cadence, range of motion, ground force reaction and joint moments, as well as functional scores, while wearing AFO. CONCLUSIONS: Overall, the use of AFO in children with spastic bilateral CP minimizes the impact of pathological gait, consistently improving some kinematic, kinetic, and spatial-temporal parameters, and making their gait closer to that of typically developing children. Creating a standardized protocol for future studies involving AFO would facilitate the reporting of new scientific data and help clinicians use their clinical reasoning skills to recommend the best AFO for their patients.

Concurrent validity of an inertial measurement system in tennis forehand drive.

The kinematic analysis in tennis forehand drive is crucial to understand the quality of this technique. The inertial measurement units (IMUs) due to its portability, occlusion free, larger capturing area and faster set up preparation, present an alternative to the optical motion capture systems (OS) considered a reference criterion system, however the degree of accuracy is task specific. This study aimed to compare the concurrent validity of a IMUs (Xsens MVN system) with an OS (Qualisys AB) for measuring upper and lower limb kinematics. Variables were evaluated during the forehand drive acceleration phase performed by 29 participants. The results demonstrated an excellent coefficient of multiple correlation (CMC) values (CMC ≥ 0.95), for the majority of the variables with exception of shoulder in the anteroposterior plane (CMC: 0.85), and elbow in the axial plane (CMC: 0.79). Root-mean-square error (RMSE) were considered from good to tolerable (1.5° ≤ RMSE ≤ 6.7°), with exception of the elbow joint angle in transverse plane (RMSE: 13.1°). One dimensional (1D) statistical parametrical mapping (SPM) demonstrated good agreement between the two systems, with exception of elbow in transverse plane. The present work presents an important advancement to a more frequently use of the IMU's in tennis, as well as in other racket sports.

Blood Flow Restriction Alters Motor Unit Behavior During Resistance Exercise.

We aimed to determine whether blood flow restriction (BFR) alters the characteristics of individual motor units during low-intensity (LI) exercise. Eight men (26.0±3.8 yrs) performed 5 sets of 15 knee extensions at 20% of one-repetition maximum (with and without BFR). Maximal isometric voluntary contractions (MVC) were performed before and after exercise to quantify force decrement. Submaximal isometric voluntary contractions were additionally performed for 18 s, matching trapezoidal target-force trajectories at 40% pre-MVC. EMG activity was recorded from the vastus lateralis muscle. Then, signals were decomposed to extract motor unit recruitment threshold, firing rates and action potential amplitudes (MUAP). Force decrement was only seen after LI BFR exercise (-20.5%; p<0.05). LI BFR exercise also induced greater decrements in the linear slope coefficient of the regression lines between motor unit recruitment threshold and firing rate (BFR: -165.1±120.4 vs. non-BFR: -44.4±33.1%, p<0.05). Finally, there was a notable shift towards higher values of firing rate and MUAP amplitude post-LI BFR exercise. Taken together, our data indicate that LI BFR exercise increases the activity of motor units with higher MUAP amplitude. They also indicate that motor units with similar MUAP amplitudes become activated at higher firing rates post-LI BFR exercise.

Three-Dimensional Kinetic Adaptations of Gait throughout Pregnancy and Postpartum.

Biomechanical adaptations that occur during pregnancy can lead to changes on gait pattern. Nevertheless, these adaptations of gait are still not fully understood. The purpose was to determine the effect of pregnancy on the biomechanical pattern of walking, regarding the kinetic parameters. A three-dimensional analysis was performed in eleven participants. The kinetic parameters in the joints of the lower limb during gait were compared at the end of the first, second, and third trimesters of pregnancy and in the postpartum period, in healthy pregnant women. The main results showed a reduction in the normalized vertical reaction forces, throughout pregnancy, particularly the third peak. Pregnant women showed, during most of the stance phase, medial reaction forces as a motor response to promote the body stability. Bilateral changes were observed in hip joint, with a decrease in the participation of the hip extensors and in the eccentric contraction of hip flexors. In ankle joint a decrease in the participation of ankle plantar flexors was found. In conclusion, the overall results point to biomechanical adjustments that showed a decrease of the mechanical load of women throughout pregnancy, with exception for few unilateral changes of hip joint moments.

Análise de equações preditivas da gordura corporal em jovens atletas de "taekwondo" / Analysis of predictive equations of body fat in young taekwondo athletes / Análisis de ecuaciones predictivas de la grasa corporal en atletas jóvenes de taekwondo

Devido à falta de métodos acessíveis válidos para mensurar o percentual de gordura corporal (%G) de taekwondistas adolescentes (TKDA), objetivou-se analisar seis equações antropométricas de predição do %G, em cinco TKDA (12,23 anos ± 1,60), utilizando como método de referência a Densitometria Radiológica de Dupla Energia (DEXA). Os %G estimados pelas equações foram comparados pelo teste t-student, regressão linear e Bland e Altman (B&A) com os obtidos por DEXA. Apenas a equação de Slaughter et al. (1988) foi adequada pelo cálculo amostral, e embora tenha subestimado o %G (em 4,85% ± 0,98), esta apresentou alta correlação (R = 0,935; R² = 0,874 EPE = 1,01) e baixa amplitude nos limites de concordância a 95% (3,84%) pelo B&A em comparação com a DEXA. Portanto, esta equação mostrou-se adequada para a predição do %G em TKDA, desde que seja corrigida pela equação de ajuste [%G (DEXA) = 1,64 + 1,24 • %G (Eq 4)] gerada pela regressão linear.

Due to the lack of valid and accessible tests to measure the body fat percentage (BF%) of adolescent taekwondo athletes (TKDA), this study aimed to analyze six anthropometric equations in the prediction of BF% with the Dual-Energy-x-Ray (DEXA) as referential method for five TKDA (12.23 years ± 1.60). The BF% estimated by the equations were compared with DEXA values using the t-student , linear regression and Bland & Altman (B&A) tests. Only the equation of Slaughter et al. (1988) was adequated by the sample size calculation, and although it subestimated the BF% (in 4.85% ± 0.98), it showed a high correlation (R = 0.935; R² = 0.874 EPE = 1.01) and low amplitude in the limits of agreement at 95% (3.84%) by B&A in comparison to DEXA. However, this equation is adequated to predict the BF% in TKDA, if it's corrected by the adjustement equation [%G (DEXA) = 1,64 + 1,24•%G (Eq 4)] generated by linear regression.

Debido a la falta de métodos accesibles válidos para medir el porcentaje de grasa del cuerpo (%G) de atletas de taekwondo adolescentes (TKDA), destinada a analizar seis ecuaciones antropométricas de predicción de %G, en cinco TKDA (12,23 años ± 1,60 ), utilizando como método de referencia la Densitometría Radiológica de Energía Dual (DEXA). El %G estimado por las ecuaciones fue comparado mediante la prueba t-student, regresión lineal y Bland & Altman (B&A) con los que se obtienen mediante DEXA. Sólo la ecuación del SLAUGHTER et al. (1988) fue adecuada para el cálculo del tamaño de la muestra y, a pesar de que había subestimado la %G (4,85 % ± 0,98 ), este mostró una alta correlación (R = 0,935 ; R2 = 0,874 EPE = 1,01 ) y baja amplitud dentro de los límites de concordancia con el 95% (3,84 %) por B&A en comparación con la DEXA. Por lo tanto, esta ecuación demostró ser adecuada para la predicción de %G en TKDA, desde que corrigida mediante la siguiente ecuación de ajuste [ %G (DEXA) = 1,64 + 1,24 • %G (eq 4)] generada mediante regresión lineal.

Accuracy of a transformation method to estimate muscle attachments based on three bony landmarks.

In this work, the accuracy of a transformation method to estimate muscle attachments based on three bony landmarks was assessed. A concept of mathematical error was introduced and applied to a data-set of 17 muscles' attachment lines from the shoulders of seven cadavers. Within the muscles' attachment lines from the studied data-set, mathematical error and anatomical variability average percentage values were 37.3 and 62.7%, respectively, for the scapula, and 54.4 and 45.6%, respectively, for the humerus. To reduce mathematical error in the transformation method presented, the plane formed by the three landmarks of the segment corresponding to the scaled muscles should neither be too close to the origin of the global coordinate system, nor too far away from muscle attachment locations to be transformed. The procedure outlined in this work allows the researcher to analyse the anatomical variability within a data-set.

A transformation method to estimate muscle attachments based on three bony landmarks.

In order to create musculoskeletal models that can be scalable to different subject specificities the calculation of the exact locations of muscle attachment is required. For this purpose, a scaling method is presented that estimates muscle attachment locations in homologous segments using three bony landmarks per segment. A data-set of 17 muscles' attachment lines from the shoulders of seven cadavers was used to assess the estimation quality of the scaling method. By knowing from the cadaver data the measured location of the muscles' attachment lines it is possible to assess the quality of the estimated ones. The scaling results showed an overall mean RMSE for the scapula and humerus muscles of 7.6 and 11.1mm, respectively. These results were then analyzed with an upper extremity model, in order to compute the influence of the RMSE in glenohumeral elevation muscle moment arms in the scapular plane. The results presented were considered to be satisfactory. Among other error contributors, the inter- and intra-subject variability should be further investigated, along with the sensitivity of a biomechanical model to these error variations.