Assessment of lower limb muscle strength can predict fall risk in patients with chronic liver disease.

Falls are caused by a combination of factors, including loss of lower limb muscle strength (LMS), and associated with declined performance status (PS). Age-related sarcopenia is generally associated with decreased muscle mass and strength of lower limb muscle but without a noticeable loss of those of upper limb or trunk muscle. However, no reports have focused on falls or LMS in chronic liver disease (CLD) patients. This study is the first to analyze the risk factors for falls in patients with CLD, focusing on LMS measurement using the Locomoscan. This study enrolled 315 CLD patients whose LMS was measured. The patients who experienced falls more than 1 year ago or during the observation period were classified as those who experienced falls. We found that risk factors for falls were PS1/2 and decreased LMS (< 0.32 N/kg). The group with sarcopenia had a higher frequency of decreased LMS (54 vs. 26%, p = 0.001) and falls (24 vs. 4.4%, p < 0.001) compared to the non-sarcopenia group. This study found that decreased LMS was an independent risk factor for falls. Assessment of LMS may be used as a better marker associated with the risk of falls in patients with CLD.

Effect of cross-slope angle on running economy and gait characteristics at moderate running velocity.

PURPOSE: Outdoor running surfaces are designed with a cross-slope, which can alter kinetic and kinematic gait parameters. The purpose of this study was to evaluate running economy, gait characteristics, and muscle activation while running on a surface with cross-slopes similar to those encountered on roads and trails. METHODS: Eleven recreational runners (females n = 6) completed 5-min running trials on a treadmill at 10 km h-1 with cross-slopes of 0, 1.15, 2.29, and 6 deg in a randomized order. RESULTS: There were no significant differences in VO2, HR, RER, or VE across cross-slope conditions. Compared to 0 deg of cross-slope, ground contact time and duty factor increased at 2.29 and 6 deg, with significant decreases in absolute and relative flight times. Rear foot angles increased in the upslope leg at 2.29 and 6 deg cross-slopes and decreased in the downslope leg at 6 deg compared to 0 deg of cross-slope, with differences between legs for the 2.29 and 6 deg conditions. Knee flexion at foot strike increased in the upslope leg at a 6 deg cross-slope. Vastus lateralis, biceps femoris, gastrocnemius, and tibialis anterior activation were not affected by the cross-slope conditions. While cross-slopes up to 6 deg result in changes to some gait kinematics, these effects do not impact running economy at moderate running velocity.

Clinical significance of dynamical network indices of surface electromyography for reticular neuromuscular control assessment.

BACKGROUND: There is currently no objective and accurate clinical assessment of reticular neuromuscular control in healthy subjects or patients with upper motor neuron injury. As a result, clinical dysfunctions of neuromuscular control could just be semi-quantified, efficacies and mechanisms of various therapies for neuromuscular control improving are difficult to verify. METHODS: Fourteen healthy participants were required to maintain standing balance in the kinetostatics model of Gusu Constraint Standing Training (GCST). A backward and upward constraint force was applied to their trunk at 0°, 20° and 25°, respectively. The multiplex recurrence network (MRN) was applied to analyze the surface electromyography signals of 16 muscles of bilateral lower limbs during the tests. Different levels of MRN network indices were utilized to assess reticular neuromuscular control. RESULTS: Compared with the 0° test, the MRN indices related to muscle coordination of bilateral lower limbs, of unilateral lower limb and of inter limbs showed significant increase when participants stood in 20° and 25° tests (P < 0.05). The indices related to muscle contribution of gluteal, anterior thigh and calf muscles significantly increased when participants stood in 20° and 25° tests (P < 0.05). CONCLUSIONS: This study applied the dynamical network indices of MRN to analyze the changes of neuromuscular control of lower limbs of healthy participants in the kinetostatics model of GCST. Results showed that the overall coordination of lower limb muscles would be significantly enhanced during performing GCST, partly by the enhancement of neuromuscular control of single lower limb, and partly by the enhancement of joint control across lower limbs. In particular, the muscles in buttocks, anterior thighs and calves played a more important role in the overall coordination, and their involvement was significantly increased. The MRN could provide details of control at the bilateral lower limbs, unilateral lower limb, inter limbs, and single muscle levels, and has the potential to be a new tool for assessing the reticular neuromuscular control. Trial registration ChiCTR2100055090.

Validity and reliability of a new hip flexor muscles flexibility assessment tool: The reactive hip flexor (RHF) test.

BACKGROUND: The modified Thomas test is the most used and most reliable test to assess the hip flexors' flexibility. However it does not evaluate the interaction of both legs. The objective of this study is to propose a new assessment tool for hip flexor flexibility, the Reactive Hip Flexion (RHF) Test. METHODS: An observational, intra-test, and test-retest study with repeated measures was carried out with the aim of assessing the validity and reliability of the RHF Test. The participants were males and females aged between 18 and 35 years old who had a training schedule of at least 2 days a week, without a musculoskeletal lower limb or lumbopelvic pathology. The reliability of the test was examined using the intraclass correlation coefficients (ICCs) by a two-way random model to establish inter-rater reliability and a two-way mixed model to assess intra-rater reliability. The precision was measured by the standard error of measurement (SEM). In addition, the minimum detectable change (MDC95%) was calculated. RESULTS: Twenty-six participants (52 hips) (47% female) completed the study. No correlations were observed between anthropometric variables and RHF peak force or active knee extension (AKE) measurements. There was an excellent intra-rater and inter-rater ICC in the hip flexors' reactive peak force and the AKE measurements, with a low SEM. CONCLUSIONS: This study demonstrated that the proposed RHF test technique is valid and reliable when used in healthy youth population.

Computational assessment of leg response to extreme loadings using a detailed finite element model.

This study focuses on evaluating the response of the Total Human Model for Safety™ lower extremity finite element model under blast loading. Biofidelity of the lower extremity model was evaluated against experiments with impact loading equivalent to underbody blast. The model response was found to match well with the experimental data for the average impactor speeds of 7 and 9.3 m/s resulting in an overall correlation and analysis rating of 0.86 and 0.82, respectively. The model response was then used to investigate response for antipersonnel mine explosion where the numerical setup consists of a charge mass of 40 g trinitrotoluene placed at a depth of 50 mm below the heel. The explosion was modeled using Multi Material-Arbitrary Lagrangian Eulerian method. The model was subjected to the graded input in terms of variation in standoff distance and mass of explosive to investigate the sensitivity of the model. The model found sensitive to the threat definition and predicted an increase of 110% in peak fluid-structure interaction force with 20% reduction in its time to peak and 29% increase in peak calcaneus axial force with a reduction of 33% in its time to peak when explosive mass varied from 40 g to 100 g. The location of the explosive below the foot was discovered to have significant effect on the injury pattern in near-field explosion. A comparative study suggested that the model predicted similar response and damage pattern compared to experimental data.

Ergonomic Assessment of a Lower-Limb Exoskeleton through Electromyography and Anybody Modeling System.

The aim of this study was to determine the muscle load reduction of the upper extremities and lower extremities associated with wearing an exoskeleton, based on analyses of muscle activity (electromyography: EMG) and the AnyBody Modeling System (AMS). Twenty healthy males in their twenties participated in this study, performing bolting tasks at two working heights (60 and 85 cm). The muscle activities of the upper trapezius (UT), middle deltoid (MD), triceps brachii (TB), biceps brachii (BB), erector spinae (ES), biceps femoris (BF), rectus femoris (RF), and tibialis anterior (TA) were measured by EMG and estimated by AMS, respectively. When working at the 60 cm height with the exoskeleton, the lower extremity muscle (BF, RF, TA) activities of EMG and AMS decreased. When working at the 85 cm height, the lower extremity muscle activity of EMG decreased except for TA, and those of AMS decreased except for RF. The muscle activities analyzed by the two methods showed similar patterns, in that wearing the exoskeleton reduced loads of the lower extremity muscles. Therefore, wearing an exoskeleton can be recommended to prevent an injury. As the results of the two methods show a similar tendency, the AMS can be used.

Investigating Temporal Kinematic Differences Caused by Unexpected Stimulation during Gait Termination through the Waveform-Level Variance Equality Test.

The efficacy of the variance equality test in steady-state gait analysis is well documented; however, temporal information on where differences in variability occur during gait subtasks, especially during gait termination caused by unexpected stimulation, is poorly understood. Therefore, the purpose of the current study was to further verify the efficacy of the waveform-level variance equality test in gait subtasks by comparing temporal kinematical variability between planned gait termination (PGT) and unplanned gait termination (UGT) caused by unexpected stimulation. Thirty-two asymptomatic male subjects were recruited to participate in the study. A Vicon motion capture system was utilized to measure lower extremity kinematics during gait termination tasks with and without unexpected stimulation conditions. The F-statistic for each interval of the temporal kinematic waveform was compared to the critical value using a variance equality test to identify significant differences in the waveform. Comparative tests between two types of gait terminations found that subjects may exhibit greater kinematics variance in most lower limb joints during UGT caused by unexpected stimulation (especially at stimulus delay and reaction phases). Significant greater variances during PGT were exhibited only in the MPJ sagittal and frontal planes at the early stimulus delay phase (4-15% and 1-15%). This recorded dataset of temporal kinematic changes caused by unexpected stimuli during gait termination is essential for interpreting lower limb biomechanical function and injury prediction in relation to UGT. Given the complexity of the gait termination task, which involves both internal and external variability, the variance equality test can be used as a valuable method to compare temporal differences in the variability of biomechanical variables.

Mechanical Energy Expenditure at Lumbar Spine and Lower Extremity Joints During the Single-Leg Squat Is Affected by the Nonstance Foot Position.

ABSTRACT: Hirsch, SM, Chapman, CJ, Frost, DM, and Beach, TAC. Mechanical energy expenditure at lumbar spine and lower extremity joints during the single-leg squat is affected by the nonstance foot position. J Strength Cond Res 36(9): 2417-2426, 2022-Previous research has shown that discrete kinematic and kinetic quantities during bodyweight single-leg squat (SLS) movements are affected by elevated foot positioning and sex of the performer, but generalizations are limited by the high-dimensional data structure reported. Using a 3D inverse dynamical linked-segment model, we quantified mechanical energy expenditure (MEE) at each joint in the kinetic chain, the total MEE (sum of MEE across aforesaid joints), and the relative contribution of each joint to total MEE during SLSs performed with elevated foot positioned beside stance leg (SLS-Side), and in-front of (SLS-Front) and behind (SLS-Back) the body. Total MEE differed between SLS variations ( p = 0.002), with the least amount observed in the SLS-Back (effect size [ES] = 0.066-0.069). Approximately 50% of total MEE was contributed by the knee joint in each SLS variation, whereas MEE at the ankle, hip, and lumbar spine (in absolute and relative terms) varied complexly as a function of the elevated foot position. Total MEE ( p = 0.0192, ES = 0.852) and the absolute MEE at the knee and spine was greater in men across the SLS variations performed ( p = 0.025-0.036, ES = 0.715-0.766), but only the lumbar spine contribution to total MEE was larger in men across all SLS variations ( p = 0.045, ES = 0.607). Otherwise, there were no other sex-specific responses observed. Biomechanically, SLS movements are generally "knee-dominant," but changing elevated foot position effectively redistributes MEE among other joints in the linkage. Consistent with the previous conclusions reached based on discrete kinematic and kinetic data, not all SLSs are equal.

Simulation-based biomechanical assessment of unpowered exoskeletons for running.

Due to the complexity and high degrees of freedom, the detailed assessment of human biomechanics is necessary for the design and optimization of an effective exoskeleton. In this paper, we present full kinematics, dynamics, and biomechanics assessment of unpowered exoskeleton augmentation for human running gait. To do so, the considered case study is the assistive torque profile of I-RUN. Our approach is using some extensive data-driven OpenSim simulation results employing a generic lower limb model with 92-muscles and 29-DOF. In the simulation, it is observed that exoskeleton augmentation leads to [Formula: see text] metabolic rate reduction for the stiffness coefficient of [Formula: see text]. Moreover, this optimum stiffness coefficient minimizes the biological hip moment by [Formula: see text]. The optimum stiffness coefficient ([Formula: see text]) also reduces the average force of four major hip muscles, i.e., Psoas, Gluteus Maximus, Rectus Femoris, and Semimembranosus. The effect of assistive torque profile on the muscles' fatigue is also studied. Interestingly, it is observed that at [Formula: see text], both all 92 lower limb muscles' fatigue and two hip major mono-articular muscles' fatigue have the maximum reduction. This result re-confirm our hypothesis that "reducing the forces of two antagonistic mono-articular muscles is sufficient for involved muscles' total fatigue reduction." Finally, the relation between the amount of metabolic rate reduction and kinematics of hip joint is examined carefully where for the first time, we present a reliable kinematic index for prediction of the metabolic rate reduction by I-RUN augmentation. This index not only explains individual differences in metabolic rate reduction but also provides a quantitative measure for training the subjects to maximize their benefits from I-RUN.

Development of the gait outcomes assessment list for lower-limb differences (GOAL-LD) questionnaire: a child and parent reported outcome measure.

BACKGROUND: To develop a priority-based patient/parent reported outcome measure for children with lower-limb differences (LD) by adapting the Gait Outcomes Assessment List (GOAL) questionnaire. METHODS: Guided by a conceptual framework of patient priorities, the GOAL questionnaire was iteratively modified and its sensibility evaluated by field-testing it on children with LD, and their parents. Cognitive interviews were conducted with a subgroup of these children, and an e-survey administered to a multidisciplinary group of health care professionals with expertise in paediatric LD. Findings were integrated to create the final version of the GOAL-LD. RESULTS: Twenty-five children (9-18 years), 20 parents, and 31 healthcare professionals evaluated the content and sensibility of the GOAL, with an emphasis on the relevance and importance of the items to patients' health related quality of life (HRQL). This resulted in the retention of 26 of the original 50 items, elimination of 12, modification of 12, and addition of seven new items. The new 45-item GOAL-LD questionnaire was shown to be sensible, and its content deemed important. CONCLUSIONS: The GOAL-LD questionnaire has a high level of face and content validity, and sensibility. It comprehensively captures the HRQL goals and outcomes that matter to children with LD and their parents. Following further psychometric evaluation, the GOAL-LD may serve as a much needed patient and parent reported outcome measure for this population.

Inter-limb strength asymmetry in adolescent distance runners: Test-retest reliability and relationships with performance and running economy.

The purpose of this investigation was, firstly, to quantify the test-retest reliability of strength measures in adolescent distance runners; and secondly, to explore the relationships between inter-limb strength asymmetry and performance and running economy (RE) in a similar cohort of young runners. For the reliability study, twelve (n = 6 female) post-pubertal adolescent distance runners performed an isometric quarter-squat on a dual force plate and unilateral isometric hip extension and hip abduction tests on two occasions. For the correlation study, participants (n = 31) performed the strength tests plus a submaximal incremental running assessment and a maximal running test. Running economy was expressed as the average energy cost of running for all speeds below lactate turnpoint and was scaled for body mass using a previously calculated power exponent. Allometrically scaled peak force during the quarter-squat and peak torque in the hip strength tasks showed acceptable levels of reproducibility (typical error ≤6.3%). Relationships between strength asymmetry and performance and RE were low or negligible (r < 0.47, p > 0.05), except for hip abduction strength asymmetry and RE in the female participants (r = 0.85, p < 0.001, n = 16). Practitioners should consider inter-limb hip abduction strength asymmetry on an individual level, and attempting to reduce this asymmetry in females may positively impact RE.

Assessment of quality of life changes in patients with lower extremity lymphedema using an advanced pneumatic compression device at home.

OBJECTIVE: Lymphedema is associated with significant morbidity and healthcare resource usage. Conventional therapy efficacy has been limited, with poor surgical salvage options. Preliminary studies have demonstrated that the use of advanced pneumatic compression devices (APCDs) improves clinical outcomes. However, limited evidence regarding their role in healthcare cost mitigation or health-related quality of life (QOL) is available. METHODS: The present postmarket, multicenter, single-arm, observational clinical trial conducted in the Veterans Affairs Healthcare System evaluated patients with a diagnosis of primary or secondary edema of unilateral or bilateral lower extremities treated with the Flexitouch APCD (Tactile Medical, Minneapolis, Minn) from February 2016 to March 2019. The patients were assessed at baseline and 12, 24, and 52 weeks from enrollment by limb circumference, QOL assessments (short form-36 and Lymphedema Quality of Life), device compliance, cellulitis episodes, and lymphedema-related healthcare use since the previous visit. The primary endpoints of interest were the QOL at baseline compared with at 12 weeks, unscheduled lymphedema-related clinic visits, and hospital admissions at 52 weeks. The secondary endpoints included the change in limb girth and QOL at 52 weeks compared with baseline. RESULTS: A total of 178 patients with lower extremity lymphedema were prospectively enrolled. The present study reports the interim data for the first 74 subjects to complete 52 weeks of APCD treatment. The cohort was predominately male (94.6%), elderly (mean age, 67 years), obese (median body mass index, 32 kg/m2), and most commonly enrolled for the treatment of phlebolymphedema (71.6%) with largely bilateral lower extremity involvement (91.9%). No significant difference was seen in QOL at 12 weeks. However, at 52 weeks, the Lymphedema Quality of Life scores had significantly improved from baseline (6.3 vs 7.4; P < .0001) and the short form-36 had demonstrated significant improvement from baseline in the physical component (38.6 vs 40.8; P = .035), with an effect toward overall improvement in the mental component (49.9 vs 51.3; P = .549). The limb circumference had decreased significantly at 12 weeks compared with baseline (28.5 cm vs 27.7 cm; P = .0005) in the most affected lower extremity, and this reduction had remained stable for the study duration. APCD treatment was associated with a significant reduction in cellulitis episodes (24.3% vs 8.1%; P = .005), lymphedema-related clinic visits (2.2 vs 0.7; P = .02), urgent care visits (1.2 vs 0.3; P = .004), and hospital admissions (0.5 vs 0.1; P = .047) per patient. CONCLUSIONS: The Flexitouch APCD resulted in initial significant limb girth reduction as early as 12 weeks and a steady and sustained improvement in health-related QOL for ≤1 year. The latter was likely reflective of a decrease in cellulitis episodes and fewer associated lymphedema-related clinic and urgent care visits and hospital admissions.

Assessing the Validity and Reliability of A Low-Cost Microcontroller-Based Load Cell Amplifier for Measuring Lower Limb and Upper Limb Muscular Force.

Lower and upper limb maximum muscular force development is an important indicator of physical capacity. Manual muscle testing, load cell coupled with a signal conditioner, and handheld dynamometry are three widely used techniques for measuring isometric muscle strength. Recently, there is a proliferation of low-cost tools that have potential to be used to measure muscle strength. This study examined both the criterion validity, inter-day reliability and intra-day reliability of a microcontroller-based load cell amplifier for quantifying muscle strength. To do so, a low-cost microcontroller-based load cell amplifier for measuring lower and upper limb maximal voluntary isometric muscular force was compared to a commercial grade signal conditioner and to a handheld dynamometer. The results showed that the microcontroller-based load cell amplifier correlated nearly perfectly (Pearson's R-values between 0.947 to 0.992) with the commercial signal conditioner and the handheld dynamometer, and showed good to excellent association when calculating ICC scores, with values of 0.9582 [95% C.I.: 0.9297-0.9752] for inter-day reliability and of 0.9269 [95% C.I.: 0.8909-0.9533] for session one, intra-day reliability. Such results may have implications for how the evaluation of muscle strength measurement is conducted in the future, particularly for offering a commercial-like grade quality, low cost, portable and flexible option.

The exoskeleton expansion: improving walking and running economy.

Since the early 2000s, researchers have been trying to develop lower-limb exoskeletons that augment human mobility by reducing the metabolic cost of walking and running versus without a device. In 2013, researchers finally broke this 'metabolic cost barrier'. We analyzed the literature through December 2019, and identified 23 studies that demonstrate exoskeleton designs that improved human walking and running economy beyond capable without a device. Here, we reviewed these studies and highlighted key innovations and techniques that enabled these devices to surpass the metabolic cost barrier and steadily improve user walking and running economy from 2013 to nearly 2020. These studies include, physiologically-informed targeting of lower-limb joints; use of off-board actuators to rapidly prototype exoskeleton controllers; mechatronic designs of both active and passive systems; and a renewed focus on human-exoskeleton interface design. Lastly, we highlight emerging trends that we anticipate will further augment wearable-device performance and pose the next grand challenges facing exoskeleton technology for augmenting human mobility.

A biarticular passive exosuit to support balance control can reduce metabolic cost of walking.

Nowadays, the focus on the development of assistive devices just for people with mobility disorders has shifted towards enhancing physical abilities of able-bodied humans. As a result, the interest in the design of cheap and soft wearable exoskeletons (called exosuits) is distinctly growing. In this paper, a passive lower limb exosuit with two biarticular variable stiffness elements is introduced. These elements are in parallel to the hamstring muscles of the leg and controlled based on a new version of the FMCH (force modulated compliant hip) control framework in which the force feedback is replaced by the length feedback (called LMCH). The main insight to employ leg length feedback is to develop a passive exosuit. Fortunately, similar to FMCH, the LMCH method also predicts human-like balance control behaviours, such as the VPP (virtual pivot point) phenomenon, observed in human walking. Our simulation results, using a neuromuscular model of human walking, demonstrate that this method could reduce the metabolic cost of human walking by 10%. Furthermore, to validate the design and simulation results, a preliminary version of this exosuit comprised of springs with constant stiffness was built. An experiment with eight healthy subjects was performed. We made a comparison between the walking experiments while the exosuit is worn but the springs were slack and those when the appropriate springs were contributing. It shows that passive biarticular elasticity can result in a metabolic reduction of 14.7 [Formula: see text] 4.27%. More importantly, compared to unassisted walking (when exosuit is not worn), such a passive device can reduce walking metabolic cost by 4.68 [Formula: see text] 4.24%.

Assessment of load on the lumbar spine using two computerised packages and REBA method.

PURPOSE: The aim of the research was a comparative analysis of the back lumbar load assessment using three methods: two with continuous input data and evaluation procedures based on mathematical relationships (ShiftBack, 3DSSPP) and one method with categorized input data and tabular load estimation procedures (REBA). METHODS: For the analysis, work activities and the value of applied force were selected. Among the analyzed 24 work activities were those during which there was a symmetrical load, as well as those during which the applied force or the assumed position of the body caused a lack of load symmetry. RESULTS: The results show that the REBA method differentiates 24 cases of unit load into six levels, while the other two methods provide 24 different values between cases. Cases differing in load even over 100%, when assessed according to the 3DSSPP or ShiftBack do not differ in the assessment of REBA. Differences in the assessment of the same tasks between the results obtained from 3DSSPP and ShiftBack that were above 15% concern only 7 cases. CONCLUSIONS: A comparative analysis of the assessment of the lumbar part of the back using three methods indicates strong correlations between the results of the assessment carried out using 3DSSPP and ShiftBack. Smaller relationships were demonstrated by comparing these two methods with the REBA method.

Biomechanical factors affecting energy cost during running utilising different slopes.

This study aimed to examine the characteristics of electromyography (EMG) and kinematics of the supporting leg affecting energy cost while running at incline, level, and decline slopes. Twelve male Japanese middle- and long-distance runners volunteered for this study. The subjects were asked to run at 13.5 km·h-1 on a treadmill under three slope conditions. Sagittal plane kinematics and the EMG of the lower limb muscles, respiratory gases were recorded. Energy cost differed significantly between slopes, being the lowest in decline slope and the greatest in incline slope. Integrated EMG (iEMG) of leg extensor muscles was greater in the incline slope than in the decline slope, and iEMG of the gastrocnemius and soleus muscles correlated positively with energy cost. The knee and ankle joint kinematics were associated with energy cost during running. In incline slope, the knee and ankle joints were more extended (plantarflexed) to lift the body. These movements may disturb the coordination between the ankle and knee joints. The gastrocnemius muscle would do greater mechanical work to plantarflex the ankle joint rather than transfer mechanical energy as well as greater mechanical work of mono-articular muscles. These muscular activities would increase energy cost.

Influence of excess weight on lower-extremity vertical stiffness and metabolic cost of walking.

The purpose was to test whether lower-extremity vertical stiffness and gait mechanics explain differences in energy cost of walking (Cw) between individuals with normal weight (NW) and obesity (OB). Ten OB (33.1 ± 2.0 kg m-2) and 10 NW (24.2 ± 1.3 kg m-2) walked for six minutes on an instrumented treadmill at 1.25 m s-1 while Cw, lower-extremity kinematics, and vertical stiffness (K vert) were measured. NW completed another trial with a loaded vest (NWL) to simulate the BMI of the obese group. Cw was 24% greater in OB (277.5 ± 45.3 J m-1) and 23% greater in NWL (272.7 ± 35.7 J m-1) than NW (211.0 ± 27.0 J m-1, P < 0.005). Mass-specific Cw (Cwkg) wasn't different between conditions (P = 0.085). Lower-extremity K vert was 40% higher in OB (32.7 ± 5.2 kN m-1) than NW (23.3 ± 4.7 kN m-1, P < 0.001), but neither was different from NWL (27.5 ± 3.4 kN m-1, P > 0.05). Mass-specific K vert (P = 0.081) was similar across conditions. K vert was related to Cw (r = 0.55, P = 0.001). Cwkg wasn't different between NW or OB, but there was a negative correlation between BMI and Cwkg driven by lower Cwkg in NWL. Cw and K vert covaried in proportion to body mass, but mass-specific K vert was unrelated to Cwkg. Mass-specific K vert was lower in NWL than OB due to NWL's greater angle of attack, center of mass displacement, and joint range of motion.

Fitness for health assessment in unilateral lower limb amputation: The Evam1 battery.

BACKGROUND: During the rehabilitation phase, physical exercise is a key element that requires an assessment of the best alternatives for application since the pre-prosthetic phase (PPF) for an accurate prescription. Therefore, the assessment of fitness for health (FFH) shall be included in the initial rehabilitation process. OBJECTIVE: To develop a FFH evaluation battery (Evam1) for pre-prosthetic unilateral lower-limb amputees (PPULLA). METHOD: A descriptive study of the theoretical construction and validation of a FFH evaluation battery based on a review of international literature for tests that measure amputee physical capability. RESULTS: During the scientific literature review, no batteries designed with this goal were found. We therefore designed a battery that was assembled of five tests for anthropometry, aerobic capacity, strength and flexibility. Combined leg and arm cycloergometrics, isokinetic dynamometry, and flexi test are the most reliable tests for the corresponding assessment of each component. CONCLUSIONS: PPF is of great importance, since the basic physical capabilities are altered due to long immobilization and hospitalization periods, inadequate postures, alteration of basic daily activities, and decrease in participation in sports, recreational, and work activities. This is a fundamental proposal, given that the procedures for FFH assessment of PPULLA have been rarely addressed, thus limiting the information on assessment methods, processes and/or tests established for these procedures.

Fractional Limb Volume in Spina Bifida Fetuses as an Assessment Tool for Postnatal Ambulation.

BACKGROUND: Prenatal fractional limb volume (FLV) can be used to assess muscle atrophy in fetuses with myelomeningocele. OBJECTIVE: We hypothesize that FLV in fetal myelomeningocele (fMMC) repair is different from postnatal repair (PNR). Assessing intrauterine muscle development can predict ambulation. METHODS: A prospective observational study was performed from July 2012 to April 2016. Demographics, clinical outcomes, and FLV of the fetal thigh were assessed by ultrasound. Ambulation videos were collected from patients over 30 months of age. FLV was compared between the fMMC and PNR groups and between ambulators and non-ambulators. Two-sample t test, ANOVA, Spearman's rho correlation, and Bland-Altman plots were used for analysis. A p value <0.05 was used for statistical significance. RESULTS: Fifty-nine patients were included, 24 had fMMC and 35 had PNR. Videos were obtained in 47 cases (73%). There was no difference in baseline demographics between the groups. There was no significant change in the fMMC group between the FLV at initial presentation and the repeat at 34 weeks gestation (54.5 ± 28.2 and 62.2% ± 16.4; p = 0.6). In contrast, the FLV in the PNR decreased between the initial evaluation and the repeat at 34 weeks (54.1 ± 27.7 to 35.8 ± 34.1%; p = 0.04). FLV at 34 weeks gestation was higher in the fMMC group as compared to the PNR group (62.2 ± 16.4 vs. 35.8 ± 34.1%; p = 0.02). There was no difference in FLV between ambulators and non-ambulators either at initial evaluation (p = 0.8) or at 34 weeks gestation (p = 0.6). CONCLUSION: Lower FLV in the PNR group compared to fMMC may suggest in utero muscle atrophy. No correlation was seen between FLV and subsequent ambulation; however, future larger studies may be needed.