Changes of kinematic parameters of lower extremities with gait speed: a 3D motion analysis study

3D motion analysis dataset of healthy young adult volunteers walking and running on overground and treadmill

Used on clinical and sportive context, three-dimensional motion analysis is considered as the gold standard in the biomechanics field. The proposed dataset has been established on 30 asymptomatic young participants. Volunteers were asked to walk at slow, comfortable and fast speeds, and to run at comfortable and fast speeds on overground and treadmill using shoes. Three dimensional trajectories of 63 reflective markers, 3D ground reaction forces and moments were simultaneously recorded. A total of 4840 and 18159 gait cycles were measured for overground and treadmill walking, respectively. Additionally, 2931 and 18945 cycles were measured for overground and treadmill running, respectively. The dataset is presented in C3D and CSV files either in raw or pre-processed format. The aim of this dataset is to provide a complete set of data that will help for the gait characterization during clinical gait analysis and in a sportive context. This data could be used for the creation of a baseline database for clinical purposes to research activities exploring the gait and the run.

Gait signature changes with walking speed are similar among able-bodied young adults despite persistent individual-specific differences

Understanding individuals' distinct movement patterns is crucial for health, rehabilitation, and sports. Recently, we developed a machine learning-based framework to show that "gait signatures" describing the neuromechanical dynamics governing able-bodied and post-stroke gait kinematics remain individual-specific across speeds. However, we only evaluated gait signatures within a limited speed range and number of participants, using only sagittal plane (i.e., 2D) joint angles. Here we characterized changes in gait signatures across a wide range of speeds, from very slow (0.3 m/s) to exceptionally fast (above the walk-to-run transition speed) in 17 able-bodied young adults. We further assessed whether 3D kinematic and/or kinetic (ground reaction forces, joint moments, and powers) data would improve the discrimination of gait signatures. Our study showed that gait signatures remained individual-specific across walking speeds: Notably, 3D kinematic signatures achieved exceptional accuracy (99.8%, confidence interval (CI): 99.1-100%) in classifying individuals, surpassing both 2D kinematics and 3D kinetics. Moreover, participants exhibited consistent, predictable linear changes in their gait signatures across the entire speed range. These changes were associated with participants' preferred walking speeds, balance ability, cadence, and step length. These findings support gait signatures as a tool to characterize individual differences in gait and predict speed-induced changes in gait dynamics.

Beyond gait speed: exploring the added value of Inertial Measurement Unit-based measurements of gait in the estimation of the walking ability in daily life

BACKGROUND

Gait speed is often used to estimate the walking ability in daily life in people after stroke. While measuring gait with inertial measurement units (IMUs) during clinical assessment yields additional information, it remains unclear if this information can improve the estimation of the walking ability in daily life beyond gait speed.

OBJECTIVE

We evaluated the additive value of IMU-based gait features over a simple gait-speed measurement in the estimation of walking ability in people after stroke.

METHODS

Longitudinal data during clinical stroke rehabilitation were collected. The assessment consisted of two parts and was administered every three weeks. In the first part, participants walked for two minutes (2MWT) on a fourteen-meter path with three IMUs attached to low back and feet, from which multiple gait features, including gait speed, were calculated. The dimensionality of the corresponding gait features was reduced with a principal component analysis. In the second part, gait was measured for two consecutive days using one ankle-mounted IMU. Next, three measures of walking ability in daily life were calculated, including the number of steps per day, and the average and maximal gait speed. A gait-speed-only Linear Mixed Model was used to estimate the association between gait speed and each of the three measures of walking ability. Next, the principal components (PC), derived from the 2MWT, were added to the gait-speed-only model to evaluate if they were confounders or effect modifiers.

RESULTS

Eighty-one participants were measured during rehabilitation, resulting in 198 2MWTs and 135 corresponding walking-performance measurements. 106 Gait features were reduced to nine PCs with 85.1% explained variance. The linear mixed models demonstrated that gait speed was weakly associated with the average and maximum gait speed in daily life and moderately associated with the number of steps per day. The PCs did not considerably improve the outcomes in comparison to the gait speed only models.

CONCLUSIONS

Gait in people after stroke assessed in a clinical setting with IMUs differs from their walking ability in daily life. More research is needed to determine whether these discrepancies also occur in non-laboratory settings, and to identify additional non-gait factors that influence walking ability in daily life.

Investigation of normal knees kinematics in walking and running at different speeds using a portable motion analysis system

Walking and running at different speeds are common in daily life. This study investigated 6 degrees of freedom (DOF) kinematics of normal knees of Chinese during walking and running. Forty healthy participants were investigated in 4 conditions: comfortable walking, normal walking, slow running and ordinary running. The range of motion (ROM) and peak values in 6 DOF kinematics were analysed. As the speed increased, a general increase in flexion, lateral and proximal translations occurred. Significant increases of ROM in flexion/extension, axial rotation and medial/lateral translations were observed. The ROM of adduction/abduction, anterior/posterior and proximal/distal translations were greatest during normal walking. The maximum and minimum flexion/extension, maximum internal rotation and tibial lateral translations increased with the increase of speed. The maximum and minimum tibial proximal translations in running were found being greater than walking. A phenomenon between walking and running was observed: both tibial proximal/distal and medial/lateral translations increased when changed from walking to running. Non-linear transition exists in 6 DOF kinematics during walking to running. Discoveries in this study may have potential clinical values to serve as references of normal walking and running in the management of knee injury and knee rehabilitation.

The nature of gait biomechanics changes with walking speed increase in patients with anterior cruciate ligament injury

BACKGROUND

This study on gait biomechanics is based on a functional test (FT) performed at free and fast walking speeds.

OBJECTIVE

We investigated the pattern of changes in gait biomechanical parameters and the knee function in patients after anterior cruciate ligament (ACL) injury or its reconstruction.

METHODS

The study included 51 patients (33 males, 18 females) with a confirmed recent or old history of ACL tear, before or after reconstruction (26 patients). Mocap data was obtained using an inertial system. All patients were divided into three groups: 41 patients with physiological response (compensation), 6 patients with signs of decompensation, and 4 non-assessable patients.

RESULTS

Increase in gait speed was associated with decrease in the walking cycle duration, stance and double support phases. In the compensation group, the physiological response of the knee was manifested in increased amplitudes. In the decompensation group, the amplitudes remained unchanged or decreased. In the compensation group, there were increases in the symmetrical muscle activity. The decompensation group was characterized by electromyography asymmetry.

CONCLUSION

The observed universal physiological mechanism limiting the load on the damaged joint can be used for accurate assessment of the knee functional state in various periods of rehabilitation.

Neuro-Rehabilitation Therapy with T-FLEX Ankle Exoskeleton and Serious Games: A Case Study

Acquired Brain Injury (ABI) causes permanent disabilities, such as foot drop. This condition affects the gait pattern, increasing the metabolic cost and risk of falling. Robotics with serious games has shown promising results in the gait rehabilitation context. This paper aims to analyze the effects of using the T-FLEX exoskeleton with (1) Automated Therapy (AT) and (2) Serious Game Therapy (SGT) in two ABI patients. Each participant completed six assisted sessions for each strategy. Results showed that AT increases the user-robot interaction torque by 10% for the first patient and 70% for the second patient, and SGT decreases by 5% for both patients. This way, SGT required the patient to generate torque to execute the ankle movement, while AT did the opposite, resulting in greater device assistance. In the functional assessment, SGT induced variations greater than 50% for the paretic ankle and knee's range of motion (ROM), indicating a potential for motor recovery. Thus, SGT led to improved ankle control and increased gait speed compared to AT. These findings suggest that SGT may be an effective rehabilitation strategy for ABI-related foot drop patients.

Comparative study of young-old and old-old people using functional evaluation, gait characteristics, and cardiopulmonary metabolic energy consumption

BACKGROUND

Walking is an important factor in daily life. Among older adults, gait function declines with age. In contrast to the many studies revealing gait differences between young adults and older adults, few studies have further divided older adults into groups. The purpose of this study was to subdivide an older adult population by age to identify age-related differences in functional evaluation, gait characteristics and cardiopulmonary metabolic energy consumption while walking.

METHODS

This was a cross-sectional study of 62 old adult participants who were classified into two age groups of 31 participants each as follows: young-old (65-74 years) and old-old (75-84 years) group. Physical functions, activities of daily living, mood state, cognitive function, quality of life, and fall efficacy were evaluated using the Short Physical Performance Battery (SPPB), Four-square Step Test (FSST), Timed Up and Go Test (TUG), Korean Version of the Modified Barthel Index, Geriatric Depression Scale (GDS), Korean Mini-mental State Examination, EuroQol-5 Dimensions (EQ-5D) questionnaire, and the Korean version of the Fall Efficacy Scale. A three-dimensional motion capture system (Kestrel Digital RealTime System®; Motion Analysis Corporation, Santa Rosa, CA, USA) and two force plates (TF-4060-B; Tec Gihan, Kyoto, Japan) were used to investigate spatiotemporal gait parameters (velocity, cadence, stride length, stride width, step length, single support, stance phase, and swing phase), kinematic variables (hip, knee, and ankle joint angles), and kinetic variables (hip, knee, and ankle joint moment and power) of gait. A portable cardiopulmonary metabolic system (K5; Cosmed, Rome, Italy) was used to measure cardiopulmonary energy consumption.

RESULTS

The old-old group showed significantly lower SPPB, FSST, TUG, GDS-SF, and EQ-5D scores (p < 0.05). Among spatiotemporal gait parameters, velocity, stride length, and step length were significantly lower in the old-old group than in the young-old group (p < 0.05). Among the kinematic variables, the knee joint flexion angles during initial contact and terminal swing phase were significantly higher in the old-old than the young-old group (P < 0.05). The old-old group also showed a significantly lower ankle joint plantarflexion angle during the pre- and initial swing phases (P < 0.05). Among the kinetic variables, the hip joint flexion moment and knee joint absorption power in the pre-swing phase were significantly lower in the old-old than the young-old group (P < 0.05).

CONCLUSION

This study demonstrated that participants 75-84 years of age had less functional gaits than their young-old counterparts (65-74 years old). As the walking pace of old-old people diminishes, driving strength to move ahead and pressure on the knee joint also tend to decrease together with stride length. These differences in gait characteristics according to age among older adults could improve our understanding of how aging causes variations in gait that increase the risk of falls. Older adults of different ages may require customized intervention plans, such as gait training methods, to prevent age-related falls.

TRIAL REGISTRATION

Clinical trials registration information: ClinicalTrials.gov Identifier: NCT04723927 (26/01/2021).

Exploring variations in gait patterns and joint motion characteristics in school-aged children across different walking speeds: a comprehensive motion analysis study

This study aimed to investigate differences in gait patterns among individuals with different walking speeds and identify the range of motion (ROM) and angular velocity for various joints during gait. Forty-five schoolchildren were randomly selected for this study. To capture their walking patterns, two FDR-AX700 4K HDR camcorders were positioned to observe the predetermined walkway. Each participant completed a 5-meter walk at various speeds, including slow, normal, and fast, while maintaining a straight stride. There were significantly higher ROM and angular velocity (p<0.05) at the hip, knee, and ankle joints across most stages of walking at a faster speed compared to slow and normal speeds. At the same time, the angular velocity was significantly higher at the hip joint during hip extension terminal stance at normal speed compared to slow and fast speeds (p<0.05, ƞ2 =0.74). Similarly, the ROM of knee flexion swing, ankle plantar flexion loading response, and ankle dorsiflexion midswing angular velocity were significantly higher during normal walking speed (p<0.05). Conversely, slow-speed walking showed significantly higher ROM at knee extension terminal swing (ƞ2=0.52) and ankle dorsiflexion terminal stance (ƞ2=0.78) (p<0.05). The results indicate that individuals with different walking speeds exhibit significant differences in gait patterns. Slower walking speeds resulted in lower gait velocity and different joint motions compared to faster walking speeds.

Usability and effects on gait of an optimized schoolchildren backpack

BACKGROUND: Backpacks used by children is a global concern, because may cause musculoskeletal discomforts and pain. OBJECTIVE: The purpose of this study was to test the usability and effects on gait kinematics wearing the Trunkpack versus a traditional backpack and no backpack. METHODS: Twenty-four children (9 to 11 years old) from a public school participated in this study. The usability was evaluated after a five-week testing period using a questionnaire. Gait kinematics was evaluated (Vicon) when the children were wearing a standard backpack, an optimized backpack (Trunkpack), and no backpack. Both backpacks were loaded with 10% of body weight. RESULTS: Was observed more trunk, hip and knee flexion when the children carried a standard backpack in comparison using the Trunkpack and not carrying a backpack (p < 0.01). The Trunkpack and no backpack were similar. The Trunkpack was well accepted by the schoolchildren (81% positive responses); 79% liked the head opening, 88% liked the waist straps, and 83% liked the facility to put and take objects in and out of the Trunkpack. CONCLUSION: Trunkpack requires less postural adjustments during gait than a standard backpack. Gait kinematics with the Trunkpack was comparable to the gait without carrying a backpack.

Effects of Dynamic IMU-to-Segment Misalignment Error on 3-DOF Knee Angle Estimation in Walking and Running

The inertial measurement unit (IMU)-to-segment (I2S) alignment is an important part of IMU-based joint angle estimation, and the accurate estimation of the three degree of freedom (3-DOF) knee angle can provide practical support for the evaluation of motions. In this paper, we introduce a dynamic weight particle swarm optimization (DPSO) algorithm with crossover factor based on the joint constraint to obtain the dynamic alignment vectors of I2S, and use them to perform the quaternion-based 3-DOF knee angle estimation algorithm. The optimization algorithm and the joint angle estimation algorithm were evaluated by comparing with the optical motion capture system. The range of 3-DOF knee angle root mean square errors (RMSEs) is 1.6°-5.9° during different motions. Furthermore, we also set up experiments of human walking (3 km/h), jogging (6 km/h) and ordinary running (9 km/h) to investigate the effects of dynamic I2S misalignment errors on 3-DOF knee angle estimation during different motions by artificially adding errors to I2S alignment parameters. The results showed differences in the effects of I2S misalignment errors on the estimation of knee abduction, internal rotation and flexion, which indicate the differences in knee joint kinematics among different motions. The IMU to thigh misalignment error has the greatest effect on the estimation of knee internal rotation. The effect of IMU to thigh misalignment error on the estimation of knee abduction angle becomes smaller and then larger during the two processes of switching from walking to jogging and then speeding up to ordinary running. The effect of IMU to shank misalignment error on the estimation of knee flexion angle is numerically the largest, while the standard deviation (SD) is the smallest. This study can provide support for future research on the accuracy of 3-DOF knee angle estimation during different motions.

Effects of change in walking speed on time-distance parameters in post-stroke hemiplegic gait

OBJECTIVES

In stroke patients, the assessment of gait ability over time is important. For quantitative gait assessment using measuring devices, the walking speed condition for measurement is generally based on the patient's preferred walking speed or the maximum walking speed at the time of measurement. However, because walking speed often increases during the convalescent stage, understanding the effects of change in walking speed on gait when comparing the course of recovery is necessary. Although several previous studies have reported the effects of change in walking speed on gait in stroke patients, the time-distance parameters described in these reports may not be generalizable because of the small case numbers. Therefore, we measured treadmill gait at the preferred walking speed (PWS) and 1.3 times the PWS (130% PWS) in 43 post-stroke hemiplegic patients and analyzed the effects of change in walking speed on time-distance parameters.

METHODS

Forty-three patients with hemiplegia after a first stroke, who were able to walk on a treadmill under supervision, were recruited as subjects. Using a three-dimensional motion analysis system, treadmill gait was assessed under two conditions: PWS and 130% PWS. The primary outcome measures were the time-distance parameters, which were compared between the PWS and 130% PWS conditions.

RESULTS

Cadence, stride length, and step length of the affected and unaffected lower limbs increased significantly at 130% PWS compared with at PWS. In terms of actual time, single stance time and initial and terminal double stance time in both affected and unaffected limbs decreased significantly at 130% PWS. In terms of relative time (% of the gait cycle), compared with PWS, relative single stance time increased significantly, whereas relative initial and terminal double stance times decreased significantly at 130% PWS in both the affected and unaffected limbs.

CONCLUSIONS

This study on treadmill gait in patients with hemiplegia after a first stroke confirmed the effects of change in walking speed on time-distance parameters. Our results will help in the interpretation of time-distance parameters measured under different walking speed conditions.

Upslope walking increases anterior tibial translation deficiency in patients with generalized joint hypermobility

BACKGROUND

Generalized joint hypermobility (GJH) is a highly prevalent disease that frequently affects the knee joint. The current literature has conflicting results about whether patients with GJH had knee kinematics deficiency during gait. This could be because most of the testing environment (level walking) was gentle and low-demanding for patients when studying their knee kinematics. With a high-demanding knee function and sagittal firm structure requirement, upslope walking was thought to stimulate sagittal knee kinematics deficiency in patients with GJH.

RESEARCH QUESTIONS

However, only little investigation reported whether upslope walking could stimulate knee kinematic deficiency or not. We hypothesize that upslope walking can increase sagittal knee kinematic deficiency between GJH subjects and healthy controls.

METHODS

A three-dimensional motion analysis was conducted to explore whether upslope walking could stimulate sagittal knee kinematic deficiency in patients with GJH. A total of 44 patients with GJH and 44 healthy controls were recruited. Subjects walked on both level and upslope (15%) conditions when the kinematic data were collected. SPM1D analysis was taken to explore the differences between groups.

RESULTS

Our results showed that upslope walking could significantly increase knee flexion angle and anterior tibial translation in both GJH patients and healthy controls (p < 0.05). The increments of anterior tibial translation (values in upslope walking minus values in level walking) of GJH patients were greater than those of healthy controls (magnitude varying from 2.5 to 2.9 mm during 0-3% gait cycles (GC), p = 0.034; 1.4-2.9 mm during 93-100%GC, p = 0.012).

SIGNIFICANCES

The findings partially confirmed our hypothesis and suggested that upslope walking could increase anterior tibial translation deficiency in patients with GJH. Upslope walking may be a practical motion task in studying the weakness of knee kinematics of GJH subjects for researchers and scholars. Patients with GJH may face a more challenging knee kinematic environment than healthy controls in up-sloped activities.

Changes in 6DOF knee kinematics during gait with decreasing gait speed

BACKGROUND

Gait speed is recognized to correlate to knee kinematic alterations. Clinically, patients with knee diseases tend to walk slowly compared to healthy controls. Hence, gait speed may serve as a confounding factor in the kinematic characteristics of patients during gait compared to healthy controls.

RESEARCH QUESTION

Whether and how gait speed affects six degrees of freedom (6DOF) knee kinematics remains unclear. The current study was designed to explore whether and how decreased gait speeds affect 6DOF knee kinematics.

METHODS

Thirty subjects (15 males and 15 females) were recruited for this study. A three-dimensional gait analysis system was used to assess the 6DOF knee kinematics of subjects at gait speeds of 4.0 km/h, 3.5 km/h, 3.0 km/h, 2.5 km/h, 2.0 km/h, 1.5 km/h, and 1.0 km/h. Kinematics of gait cycle (GC) were assessed at all gait speed levels.

RESULTS

Decreased adduction angle (0.5-3.2 °, p < 0.05), increased external rotation (0.6-3.3 °, p < 0.05) and decreased flexion angle (1.5-17.4 °, p < 0.05) were found during most GC as gait speed level decreased. Greater anterior tibial translation (0.9-2.6 mm, p < 0.05), greater proximal translation (0.4-2.4 mm, p < 0.05) and decreased lateral tibial translation (0.5-3.0 mm, p < 0.05) were found during most GC as gait speed level decreased. Gender was also found to have great effects on 6DOF knee kinematics (p < 0.05). Interactions between gender and gait speed were also found (p < 0.05).

SIGNIFICANCE

Our findings suggest that additional attention should be paid when dealing with kinematic comparisons of GC between controls and patients with significantly different gait speeds or genders than controls. Kinematic alterations induced by gait speed may raise concern for patients with knee diseases who struggle to walk faster than their normal speed. This may enhance our knowledge of the relationship between gait speed and 6DOF knee kinematics.

The use of a detailed video-based locomotor pattern analysis system to assess the functional reinnervation of denervated hind limb muscles

BACKGROUND

Spinal cord injuries induce a critical loss of motoneurons followed by irreversible locomotor function impairment. Surgical approaches combined with neuroprotective agents effectively rescue the damaged motoneurons and improve locomotor function. Our aim was to develop a reliable method which is able to provide quantifiable and in-depth data on the locomotor recovery during skeletal muscle reinnervation.

NEW METHOD

Sprague-Dawley rats underwent lumbar 4 ventral root avulsion and reimplantation followed by riluzole treatment in order to rescue the injured motoneurons of the damaged pool. Control animals were operated, but received no riluzole treatment. The locomotor pattern of the hind limb was recorded biweekly on a special runway equipped with high resolution and high speed digital cameras producing both lateral and rear views simultaneously. All together 12 parameters of the hind limb movement pattern were evaluated by measuring specific joint angles, footprints and gait parameters in single video frames. Four months after the operation Fast Blue, a fluorescent retrograde tracer was applied to the L4 spinal nerve in order to label the reinnervating motoneurons.

RESULTS

Our results confirmed the sensitivity of our arrangement and established strong relationship between the functional improvement and the morphological reinnervation. Moreover, we developed a correction method to make the system tolerant to the differences in the weight, step duration and step length.

COMPARISON WITH EXISTING METHODS

There are no commercially available cheap, multi-parametric analysing equipment to characterise the gait in its complexity.

CONCLUSIONS

Our system offers a modular, adaptable and expandable analysis on the reinnervation of the limb musculature in rodents.

Determine the kinematics and kinetics parameters associated with bilateral gait patterns among healthy, overweight, and obese adults

BACKGROUND AND AIM

Biomechanical analysis of gait is important to obtain information regarding the lower limb impairments and dysfunction during locomotion. This study aimed to determine the potential difference among healthy, overweight, and obese participants and their impact on gait parameters by observing the kinematic and kinetics parameters.

METHODS

A cross-sectional study conducted with forty (15 healthy, 12, overweight, 13 obese) male participants. All participants were non-smokers, and their physical activity level was 7000±2142 steps per day. Participants anthropometric characteristics were age:21.57±1.46 years; height:173. 63±6.43 cm, body mass;86.15±23.36 kg., body mass index (BMI) :28.57±7.68 kg/m2, body fat:29.93±9.44%. A bioelectrical impedance device was used to determine participants' body composition and health status. A portable pressure sensor mat (Walkway) from Tekscan was used to measure bilateral gait parameters kinematically and kinetically. One-way analysis of variance was used to determine the differences between groups.

RESULTS

Significant differences were found between health, overweight, and obese participant for different bilateral gait's kinematic and kinetic parameters as cadence, gait velocity, step time, step length, step velocity, step width, stride time, stride length, stride velocity, maximum force, maximum peak pressure, active propulsion, and passive propulsion except impulse at .05 level of significance.

CONCLUSIONS

The findings shows that kinematics and kinetics parameters of gait were affected by the status of their BMI. Current research suggests that increased body weight interferes with normal musculoskeletal function via a range of kinematic and kinetic deficits. More research is required to accurately understand the structural and functional restriction imposed by overweight and obese individuals.

Comparing sagittal plane kinematics and kinetics of gait and stair climbing between hypermobile and non-hypermobile people; a cross-sectional study

Background

Joint Hypermobility Syndrome (JHS) presents with a range of symptoms including widespread joint hypermobility and chronic arthralgia. The study objective was to investigate whether impairments in JHS are due to hypermobility or another factor of JHS by identifying impairments in gait and stair-climbing tasks; an activity that is demanding and so may better show differences between the cohorts.

Methods

Sixty-eight adults participated; 23 JHS, 23 Generalised Joint Hypermobility (GJH), and 22 Normal Flexibility (NF). Inclusion criteria for JHS participants were a positive classification using the Brighton Criteria, for GJH a Beighton Score ≥ 4, and for NF a Beighton Score < 4 with no hypermobile knees. Participants were recorded with a 10-camera Vicon system whilst they performed gait and stair-climbing. Temporal-spatial, and sagittal plane kinematic and kinetic outcome measures were calculated and input to statistical analyses by statistical parametric mapping (SPM).

Results

During the gait activity JHS had significantly greater stride time and significantly lower velocity than NF, and significantly greater stride time, lower velocity, and lower stride length than GJH. SPM analysis showed no significant differences between groups in gait kinematics. There were significant differences between groups for gait moments and powers; people with JHS tended to have lower moments and generate less power at the ankle, and favour power generation at the knee. A similar strategy was present in stair ascent. During stair descent people with JHS showed significantly more hip flexion than people with NF.

Conclusions

As there was only one significant difference between GJH and NF we conclude that impairments cannot be attributed to hypermobility alone, but rather other factor(s) of JHS. The results show that both gait and stair-climbing is impaired in JHS. Stair-climbing results indicate that JHS are using a knee-strategy and avoiding use of the ankle, which may be a factor for clinicians to consider during treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04549-2.

Prediction of gait trajectories based on the Long Short Term Memory neural networks

The forecasting of lower limb trajectories can improve the operation of assistive devices and minimise the risk of tripping and balance loss. The aim of this work was to examine four Long Short Term Memory (LSTM) neural network architectures (Vanilla, Stacked, Bidirectional and Autoencoders) in predicting the future trajectories of lower limb kinematics, i.e. Angular Velocity (AV) and Linear Acceleration (LA). Kinematics data of foot, shank and thigh (LA and AV) were collected from 13 male and 3 female participants (28 ± 4 years old, 1.72 ± 0.07 m in height, 66 ± 10 kg in mass) who walked for 10 minutes at preferred walking speed (4.34 ± 0.43 km.h-1) and at an imposed speed (5km.h-1, 15.4% ± 7.6% faster) on a 0% gradient treadmill. The sliding window technique was adopted for training and testing the LSTM models with total kinematics time-series data of 10,500 strides. Results based on leave-one-out cross validation, suggested that the LSTM autoencoders is the top predictor of the lower limb kinematics trajectories (i.e. up to 0.1s). The normalised mean squared error was evaluated on trajectory predictions at each time-step and it obtained 2.82-5.31% for the LSTM autoencoders. The ability to predict future lower limb motions may have a wide range of applications including the design and control of bionics allowing improved human-machine interface and mitigating the risk of falls and balance loss.

Feasibility and Reliability Assessment of Video-Based Motion Analysis and Surface Electromyography in Children with Fragile X during Gait

Fragile X Syndrome (FXS), the leading form of inherited intellectual disability and autism, is characterized by specific musculoskeletal conditions. We hypothesized that gait analysis in FXS could be relevant for the evaluation of motor control of gait, and help the understanding of a possible correlation between functional and intellectual abilities. Typical deficits in executive control and hyperactivity have hampered the use of standard gait analysis. The aim of our study was to quantitatively assess musculoskeletal alterations in FXS children in standard ambulatory conditions, in a friendly environment. Ten FXS children and sixteen controls, with typical neurodevelopment, were evaluated through four synchronized video cameras and surface electromyography; lower limb joints rotations, spatiotemporal parameters, duration of muscle contraction, activation timing and envelope peaks were determined. Reliability and repeatability of the video based kinematics analysis was assessed with respect to stereophotogrammetry. The Kruskal–Wallis Test (p < 0.05) or SPM1D were used to compare different groups of subjects. Results show a consistently altered gait pattern associated with abnormal muscle activity in FXS subjects: reduced knee and excessive hip and ankle flexion, and altered duration and activity onset on all the recorded muscles (Rectus/Biceps Femoris, Tibialis Anterior, Gastrocnemius Lateralis). Results of this study could help with planning personalized rehabilitations.

Gait Analysis 1 Year after Primary TKA: No Difference between Gap Balancing and Measured Resection Technique

Mechanical alignment in total knee arthroplasty (TKA) can be achieved using dependent bone cuts. The hypothesis is that patients have a better balanced TKA, as a result. The aim of this study was to determine if this technique is superior to an independent bone cut technique in terms of gait parameters, patient-reported outcome measures (PROMs), and satisfaction assessed before surgery and at 1-year follow-up. A total of 58 patients were evaluated before and 1 year following TKA, using the Press Fit Condylar (PFC) Sigma posterior stabilizer (PS) design; 39 (70 ± 8 years; 27 women) with independent bone cuts and 19 (71 ± 7 years; 12 women) with dependent bone cuts using the Specialist TRAM. Gait was evaluated with a three-dimensional motion analysis system for spatiotemporal and kinematics parameters. Pain and functional levels were assessed using the Western Ontario and McMaster Universities arthritis index (WOMAC); general health was assessed by the short form (SF)-12. Global satisfaction, as well as patient satisfaction, related to pain and functional levels were assessed using a five-point Likert's scale. No significant difference was found between both groups in terms of age, body mass index, pain, and functional levels at baseline. At 1-year follow-up, despite an overall improvement in gait, WOMAC, SF-12 physical score and pain, none of the patients showed gait parameters comparable to a healthy control group. No surgical technique effect was observed on gait, clinical outcomes, and satisfaction level. While observing an overall improvement at 1-year follow-up, we did not find any significant difference between the two surgical techniques in terms of gait parameters, patients' outcomes, and satisfaction.

Comparison of outcomes between gap balancing and measured resection techniques for total knee arthroplasty: A prospective, randomized, controlled trial

OBJECTIVE

The aim of this study was to compare the effect of Gap Balancing (GB) versus Measured Resection (MR) techniques on the early clinical and radiological results of Total Knee Arthroplasty (TKA).

METHODS

In this prospective study, 99 patients (99 knees) who underwent unilateral TKA between March 2018 and January 2019 were randomly allocated to one of two groups: The GP group, TKA with GB technique (19 male, 31 female; mean age = 55.9 ±16.5) and the MR group, TKA with MR technique (19 male, 30 female; mean age = 54.2 ± 18.7). Patients in both groups were comparable in terms of the demographic and clinical data. The angle of cutting block to PCA and Cutting Thickness of the Medial and Lateral Condyle (CTMC, CTLC) were intraoperatively measured. In radiographic analysis, Preoperative Mechanical Femorotibial Angle (Pre-mFTA), Postoperative Mechanical Femorotibial Angle (Post-mFTA), and joint line changes were examined. Femoral component Rotation Angle (FCRA) was also measured by computed tomography. In gait analysis, the spatiotemporal parameters (walking speed, step length, and single support time) and kinematics parameters (flexion angle, extension angle, and transversal rotation) were collected at 12 months postoperatively. Furthermore, Western Ontario and McMaster Universities Arthritis Index (WOMAC) were performed at 12 months after surgery.

RESULTS

CTMC and CTLC were both significantly higher in GB group than in the MR group (9.8±2.0 mm vs 8.5 ± 1.2 mm; 7.9 ± 1.8mm vs 6.8 ± 1.4mm; P = 0.001, P = 0.002, respectively). Angle of cutting block to PCA was statistically lower in GB group than in the MR group (1.7 ± 1.5° vs 3.1 ± 0.5 °; P < 0.001). FCRA is greater in the GB group compared to the MR group, but the difference did not reach statistical significance (1.2 ± 2.8 ° vs 0.7 ± 2.0 °; P > 0.05). Although post-mFTA significantly improved compared with pre-mFTA in both groups, no significant difference was observed in the changes of post-mFTA between the two groups (0.9 ± 1.7° vs 0.3 ± 1.8°, P > 0.05). No significant differences were determined between the two groups in spatiotemporal gait parameters including walking speed, step length, and single support time. The sagittal max knee flexion range was significantly larger in the GB group than in the MR group (49.27 ± 5.24 ° vs 45.99 ± 8.21 °, P < 0.05). The flexion range did not reach the level of the control group. There was no significant difference between the two groups in WOMAC at 12 months follow-up (P > 0.05).

CONCLUSION

Evidence from this study has revealed GB and MR techniques have both little effect on early clinical results of TKA. Nonetheless, GB technique can provide better knee flexion in the early postoperative gait status compared with MR technique.

LEVEL OF EVIDENCE

Level I, Therapeutic Study.

Walking lower extremity biomechanics of adolescents with autism spectrum disorder

Although the literature indicates children with autism spectrum disorder (ASD) walk at slower speeds and altered kinematics compared to neurotypical controls, no research has examined walking at matched speeds. This study examined biomechanical differences between adolescents with ASD and matched (age, sex, and body mass index) neurotypical controls. Lower extremity biomechanics of seventeen adolescents with ASD and seventeen controls were compared at matched speeds: self-selected and a standardized 1.3 m/s. Controls exhibited greater eversion angles and hip abduction moments compared to those with ASD. This study found adolescents, which may have a more mature gait than young children, walk with a similar pattern in the propulsive plane (i.e. sagittal) as neurotypical controls, but with alterations in the supportive plane (i.e. frontal).

Gait Variability and Relationships With Fear, Avoidance, and Pain in Adolescents With Chronic Pain

OBJECTIVE

Some children with chronic pain struggle with fear of pain, avoidance behaviors, and associated disability; however, movement adaptations in the context of chronic pain in childhood is virtually unknown. Variability in adaptive movement responses previously observed between individuals might be largely explained by the presence of problematic psychological drivers (eg, fear, avoidance). The goals of this study were to quantify the variability of gait and examine relationships among pain, fear, avoidance, function (perceived and objective), and gait variability.

METHODS

This study used a cross-sectional design. Eligible patients were between 8 and 17 years of age and had musculoskeletal, neuropathic, or headache pain that was not due to acute trauma (eg, active sprain) or any specific or systemic disease. Participants completed the Numeric Pain Rating Scale, Fear of Pain Questionnaire (FOPQ), Functional Disability Inventory, and 6-Minute Walk Test and received kinematic gait analysis. Relationships were analyzed among these measures, and the self-report and functional measures were examined to determine whether they predicted gait variability (GaitSD).

RESULTS

The 16 participants who were evaluated (13.8 [SD = 2.2] years of age; 13 female) had high Numeric Pain Rating Scale scores (6.2 [SD = 2.1]), FOPQ-Fear scores (25.9 [SD = 12.1]), FOPQ-Avoidance scores (22.8 [SD = 10.2]), and Functional Disability Inventory scores (28.6 [SD = 9.4]) and low 6-Minute Walk Test distance (437.1 m [SD = 144.6]). Participants had greater GaitSD than age-predicted norms. Fear was related to self-selected GaitSD, and avoidance was related to both self-selected and standardized GaitSD. Avoidance predicted 43% and 47% of the variability in self-selected and standardized GaitSD, respectively.

CONCLUSION

GaitSD was significantly related to both fear of pain and avoidance behaviors, suggesting the interplay of these psychological drivers with movement. FOPQ-Avoidance was robust in accounting for GaitSD.

IMPACT

This study offers preliminary evidence in understanding movement adaptations associated with adolescents with chronic pain. They may lend to more directed interventions.

Impact of cognitive tasks on biomechanical and kinematic parameters of gait in women with fibromyalgia: A cross-sectional study

BACKGROUND

Fibromyalgia (FM) is a chronic disease whose symptoms may cause altered walking pattern, which is important given the relevance of walking in daily life activities. These activities use to require the ability to perform both a motor and a cognitive task simultaneously. The main aim of the current study was to evaluate the impact of performing a simultaneous cognitive task in the gait pattern of women with FM.

METHODS

A total of 36 women recruited from a local association took part in this cross-sectional study. The time required to complete the 10-meters-walking-test and kinematic outcomes including number of steps, cadence, trunk tilt and ranges of motion were analyzed under single (motor task only) and dual task (motor and cognitive tasks simultaneously) conditions. The secondary task consisted in counting aloud backward in rows of two.

RESULTS

Results showed a significant increment in the time required to complete the test (p < 0.01) when participants performed the motor and cognitive tasks at the same time. Moreover, relevant changes in kinematic parameters such as increment of number of steps (p < 0.01), cadence (p < 0.01), trunk tilt (p < 0.01) and both hip (p < 0.01) and knee (p = 0.03) ranges of motion were also observed.

CONCLUSION

Adding a cognitive task to a primary motor task affects the walking motor pattern in women with FM, making it more stable and safer walking pattern when the attention is focused on two simultaneous tasks.

Racial differences in gait mechanics

The effect of race has rarely been investigated in biomechanics studies despite racial health disparities in the incidence of musculoskeletal injuries and disease, hindering both treatment and assessment of rehabilitation. The purpose of this study was to test the hypothesis that racial differences in gait mechanics exist between African Americans (AA) and white Americans (WA). Ninety-two participants (18-30 years old) were recruited with equal numbers in each racial group and sex. Self-selected walking speed was measured for each participant. 3D motion capture and force plate data were recorded during 7 walking trials at regular and fast set speeds. Step length, step width, peak vertical ground reaction force, peak hip extension, peak knee flexion, and peak ankle plantarflexion were computed for all trials at both set speeds. Multivariate and post-hoc univariate ANOVA models were fit to determine main and interaction effects of sex and race (SPSS V26, α = 0.05). Self-selected walking speed was slower in AA (p = 0.004, ƞ_p² = 0.088). No significant interactions between race and sex were identified. Males took longer steps (regular: p < 0.001, ƞ_p² = 0.288, fast: p < 0.001, ƞ_p² = 0.193) and had larger peak knee flexion (regular: p = 0.007, ƞ_p² = 0.081, fast: p < 0.001, ƞ_p² = 0.188) and ankle plantarflexion angles (regular: p = 0.050, ƞ_p² = 0.044, fast: p = 0.049, ƞ_p² = 0.044). Peak ankle plantarflexion angle (regular: p = 0.012, ƞ_p² = 0.071, fast: p < 0.001, ƞ_p² = 0.137) and peak hip extension angle during fast walking (p = 0.007, ƞ_p² = 0.083) were smaller in AA. Equivalency in gait measures between racial groups should not be assumed. Racially diverse study samples should be prioritized in the development of future research and individualized treatment protocols.

Applying the brakes in tennis: How entry speed affects the movement and hitting kinematics of professional tennis players

Purpose: Movement and stroke production are coupled when playing tennis but generally decoupled in training and research. This study explored the lower limb, trunk and racquet mechanics of tennis players performing running forehands at varying movement speeds. Methods: Eleven female and seven male professional tennis players hit forehand groundstrokes while travelling at different movement speeds (Low: 1.4-2.0 m s - 1 , Medium: 2.70-2.90 m s - 1 , High: 4.0-4.3 m s - 1 ). Kinematics were captured using a VICON camera system. Speed and sex effects were analysed using linear mixed-effects models. Results: Prior to impact, females increased drive leg loading kinematics, and reduced preparatory trunk rotation (-9°), while both sexes lengthened their final stride and backswing during high-speed trials. At impact, racquet-head speed was unchanged for male players but dropped 14% when females travelled at high entry speed (p < 0.001). Conclusions: Reduced trunk rotation and lower limb drive contributed to female players being unable to maintain racquet-head speed when moving at high speed. Conversely, male players generated similar racquet-head speed despite the different entry speeds necessitating lower limb joint adjustments. These findings highlight the different deceleration strategies employed by male and female tennis professionals and challenge the widely accepted training theory in tennis that emphasises hitting and moving actions being rehearsed separately.

Validity of quantitative assessment of posterior pelvic tilt and contralateral vaulting in hemiplegia using 3D treadmill gait analysis

BACKGROUND

Assessing abnormal gait patterns could indicate compensatory movements, which could be an index for recovery and a process of motor learning. To quantify the degree of posterior pelvic tilt, contralateral vaulting is necessary.

OBJECTIVES

This study aimed to develop and evaluate the validity of quantitative indices for posterior pelvic tilt and contralateral vaulting in hemiplegic patients.

METHODS

Forty-six healthy control subjects and 112 hemiplegic patients participated in this study. Of the 112 patients, 50 were selected into each abnormal gait pattern group, with some overlap. Three experienced physical therapists observed their walking and graded the severity of the two abnormalities in five levels. An index to quantify each of the two abnormal gait patterns was calculated from the three-dimensional treadmill gait analysis. The index values of patients were compared with those of healthy subjects and with the results of observational gait assessment done by three physical therapists with expertise in gait analysis.

RESULTS

The index values were significantly higher in hemiplegic patients than in healthy subjects (28.0% and 44.7% for the posterior pelvic tilt in healthy subjects and patients, respectively and 0.9 and 4.7 for the contralateral vaulting, respectively). A strong correlation was observed between the index value and the median observational rating for two abnormal gait patterns (r = -0.68 and -0.72).

CONCLUSIONS

The proposed indices for posterior pelvic tilt and contralateral vaulting are useful for clinical gait analysis, and thus encouraging a more detailed analysis of hemiplegic gait using a motion analysis system.

Parametric generation of three-dimensional gait for robot-assisted rehabilitation

For robot-assisted rehabilitation and assessment of patients with motor dysfunction, the parametric generation of their normal gait as the input for the robot is essential to match with the features of the patient to a greater extent. In addition, the gait needs to be in three-dimensional space, which meets the physiological structure of the human better, rather than only on a sagittal plane. Thus, a method for the parametric generation of three-dimensional gait based on the influence of the motion parameters and structure parameters is presented. First, the three-dimensional gait kinematic of participants is collected, and trajectories of ankle joint angle and ankle center position are calculated. Second, for the trajectories, gait features are extracted including gait events indicating the physiological features of walking gait, in addition to extremes indicating the geometrical features of the trajectories. Third, regression models are derived after using leave-one-out cross-validation for model optimization. Finally, cubic splines are fitted between the predicted gait features to generate the trajectories for a full gait cycle. It is inferred that the generated curves match the measured curves well. The method presented herein gives an important reference for research into lower limb rehabilitation robots.

Comparison of measurement protocols to estimate preferred walking speed between sites

BACKGROUND

Walking speed influences a variety of typical outcome measures in gait analysis. Many researchers use a participant's preferred walking speed (PWS) during gait analysis with a goal of trying to capture how a participant would typically walk. However, the best practices for estimating PWS and the impact of laboratory size and walk distance are still unclear.

RESEARCH QUESTION

Is measured PWS consistent across different distances and between two laboratory sites?

METHODS

Participants walked overground at a "comfortable speed" for six different conditions with either dynamic (4, 6, 10, and 400 m) or static (4 and 10 m) starts and stops at two different data collection sites. Repeated measures ANOVA with Bonferroni corrections were used to test for differences between conditions and sites.

RESULTS

Participants walked significantly faster in the 4, 6, and 10 m dynamic conditions than in the 400 m condition. On average, participants walked slower in the static trials than the dynamic trials of the same distance. There was a significant interaction of lab and condition and so results were examined within each lab. Across both labs, we found that the 4 and 10 m dynamic conditions were not different than the 6 m dynamic condition at both sites, while other tests did not provide consistent results at both sites.

SIGNIFICANCE

We recommend researchers use a 6 m distance with acceleration and deceleration zones to reliably test for PWS across different laboratories. Given some of the differences found between conditions that varied by site, we also emphasize the need to report the test environment and methods used to estimate PWS in all future studies so that the methods can be replicated between studies.

Reliability of a low-cost webcam recording system for three-dimensional lower limb gait analysis

The purposes of this study were to develop and evaluate the test-retest reliability of a specific low-cost three-dimensional webcam recording system (3D-WCRS) and compare its reliability to a standard motion analysis system. Twenty healthy volunteers comprised of 5 males and 15 females with a mean age of 22.90 years and mean BMI of 22.72 kg/m² were investigated for angles of hip, knee and ankle joints in three planes while walking at a self-selected speed. Intraclass correlation coefficients (ICCs) were used to evaluate as well as compare the test-retest reliability of the 3D-WCRS and standard motion analysis system. Standard error of measurement (SEM) was also analyzed for the purposes of the study. The results exhibited excellent test-retest reliability for the 3D-WCRS (ICCs ranged between 0.93 and 0.99, p = 0.001) in the three joints and planes. The standard motion analysis system demonstrated excellent reliability for all joints and planes (ICCs ranged between 0.99 and 1.00, p = 0.001). Minimal SEM values were observed in both the 3D-WCRS and standard motion analysis systems. Therefore, the developed low-cost 3D-WCRS exhibits good to excellent test-retest reliability. The test-retest reliability of the 3D-WCRS is likely to be comparable to a standard motion analysis system.

Changes in Gait Variables in Patients with Intermittent Claudication

Objective

Intermittent claudication (IC) is a pathological symptom with a particular effect on human gait patterns. Therefore, analyzing these patterns can facilitate rehabilitation or treatment through comparison of the values of kinematic and kinetic variables of patients with the normal values of healthy people. Therefore, the aim of this study was to find differences in the values of gait variables between patients with IC and healthy people.

Methods

The study included 98 patients diagnosed with peripheral arterial disease with IC. The patients traveled a distance of 6 m at a voluntary gait velocity. Ground reaction forces while the foot contacted the ground and kinematic variables of lower limb movements were recorded. The values of normal gait variables were computed based on the results obtained in a group of 30 healthy people.

Results

Patients used a gait velocity below the norm for healthy people. The velocity during the lower limb swing and the step and stride length in patients with IC were below the norm. Differences were also found in the ranges of motion between patients with IC and healthy people for the pelvic obliquity, pelvic rotation, hip flexion-extension, hip abduction-adduction, hip internal-external rotation, knee flexion-extension, ankle dorsi-plantar flexion, and foot progression angles.

Conclusions

The presented kinematic and kinetic characteristics measured by gait variables suggest differences between patients with IC and healthy people. Considering kinematic and kinetic gait variables during the rehabilitation process would facilitate the development of a more economic gait technique (with increased stride length and range of motion in the lower limb joints) to obtain the desired rehabilitation effects. Patients with IC should receive rehabilitation oriented towards improving mobility and increasing muscle strength in selected lower limb joints to increase gait velocity and stride length.

Down Syndrome: Gait Pattern Alterations in Posture Space Kinematics

Gait characteristics in Down syndrome (DS) are documented in terms of discrete kinematic variables. However, such features are strictly interrelated and reflect neurological and developmental delays. A phenotypical, quantitative assessment of how multi-joint walking patterns are activated and controlled during gait would enhance the understanding of locomotor mechanisms in such patients. We adopted an analysis framework based on principal component analysis: the gait kinematics of 221 patients aged 6-45 were expressed in terms of a reduced set of one-dimensional movement components. Their time course during the gait cycle was described by score vectors, here called principal positions; its second time derivative, called principal acceleration, characterized the activity of the neuromuscular controller on each component. Outcomes were compared to an age-matched group of 49 healthy individuals. After controlling for the effect of walking speed, we observed that the main alterations in gait patterns emerged in the fourth component which is mostly devoted to stability management (group differences, p < 0.001). Rather, the main sagittal-plane locomotor patterns showed only subtle differences from the control group. Using statistical parametrical mapping, we found when (step-to-step transitions) and how (interrelated joints motion) the fourth movement deviated from normal: in particular, an excessive hip adduction and trunk inclination during the transition between single and double support phases. These findings match the neurological and sensorimotor trait of DS and suggest the promotion of targeted rehabilitative interventions. Furthermore, this paper opens to the adoption of principal positions and principal accelerations to investigate the neuromuscular control of movement patterns during locomotion.

Effects of walking speed on gait biomechanics in healthy participants: a systematic review and meta-analysis

BACKGROUND

Understanding the effects of gait speed on biomechanical variables is fundamental for a proper evaluation of alterations in gait, since pathological individuals tend to walk slower than healthy controls. Therefore, the aim of the study was to perform a systematic review of the effects of gait speed on spatiotemporal parameters, joint kinematics, joint kinetics, and ground reaction forces in healthy children, young adults, and older adults.

METHODS

A systematic electronic search was performed on PubMed, Embase, and Web of Science databases to identify studies published between 1980 and 2019. A modified Quality Index was applied to assess methodological quality, and effect sizes with 95% confidence intervals were calculated as the standardized mean differences. For the meta-analyses, a fixed or random effect model and the statistical heterogeneity were calculated using the I² index.

RESULTS

Twenty original full-length studies were included in the final analyses with a total of 587 healthy individuals evaluated, of which four studies analyzed the gait pattern of 227 children, 16 studies of 310 young adults, and three studies of 59 older adults. In general, gait speed affected the amplitude of spatiotemporal gait parameters, joint kinematics, joint kinetics, and ground reaction forces with a decrease at slow speeds and increase at fast speeds in relation to the comfortable speed. Specifically, moderate-to-large effect sizes were found for each age group and speed: children (slow, - 3.61 to 0.59; fast, - 1.05 to 2.97), young adults (slow, - 3.56 to 4.06; fast, - 4.28 to 4.38), and older adults (slow, - 1.76 to 0.52; fast, - 0.29 to 1.43).

CONCLUSIONS

This review identified that speed affected the gait patterns of different populations with respect to the amplitude of spatiotemporal parameters, joint kinematics, joint kinetics, and ground reaction forces. Specifically, most of the values analyzed decreased at slower speeds and increased at faster speeds. Therefore, the effects of speed on gait patterns should also be considered when comparing the gait analysis of pathological individuals with normal or control ones.

Development of an Ankle-Foot Orthosis That Provides Support for Flaccid Paretic Plantarflexor and Dorsiflexor Muscles

ADJUST, a novel ankle-foot orthosis (AFO) that we have developed, allows the ankle a normal range of motion (ROM) while providing support for flaccid ankle-muscle paresis. It consists of two leaf-spring hinges that independently control plantarflexion and dorsiflexion stiffness. To evaluate whether ADJUST meets the minimum mechanical requirements, we quantified its ankle ROM and stiffness. To evaluate whether it meets the minimum ankle kinematic and kinetic goals for normal gait, a patient with both plantarflexor and dorsiflexor paralysis used it, and his own AFO, to walk. When fitted with stiff springs, ADJUST met all requirements and goals. During the stance and the swing phases, ankle ROM was within the normal range when ADJUST was fitted with stiff springs. Ankle ROM during stance was outside the normal range both with the patient's own AFO and with ADJUST when it was fitted with flexible springs. Power at the ankle met the minimum goal but was lower with ADJUST than with the patient's own AFO. The optimal stiffness configuration that would result in a higher power at the ankle with a normal ankle ROM was not reached for this patient. Walking with ADJUST seems feasible and could be profitable in patients with flaccid ankle muscle paresis.

Motor strategy for rapid gait initiation under conditions of limited center of pressure control

[Purpose] The general motor strategy for gait initiation is achieved by the difference between the center of gravity and center of pressure; it be as bigger under speed optimization. This study aimed to investigate the motor pattern in rapid gait initiation under conditions of limited backward displacement of center of pressure. [Participants and Methods] The participants were 30 healthy young males (mean age, 19.7 ± 1.0 years). They performed a gait initiation task at three center of pressure start positions (anterior, middle, and posterior) and two speed conditions (normal and rapid). The gait initiation motion was measured using a video camera and motor pattern in the images was classified. The center of pressure position was continuously monitored using a pressure distribution measurement system. [Results] Forward tilt pattern was the most common under no limited center of pressure control and normal speed. The backward tilt pattern was the most preferred in the posterior position under limited center of pressure control and rapid speed. Displacement of the center of pressure showed a significant decline when the center of pressure start position was displaced backward. [Conclusion] The backward tilt pattern is the most effective motor strategy to increase the forward speed of the center of gravity.

Three-Dimensional Human Gait Pattern: Reference Data for Young, Active Women Walking with Low, Preferred, and High Speeds

Normal gait pattern is the key component in the investigation of pathological gait patterns. In computer motion analysis there is a need to include data from participants with different somatic structures to develop a normative database or to limit the database results to a specific population. The aim of this study was to determine kinematic gait patterns for young, active women walking with low, preferred, and self-selected speeds with regard to their somatic characteristics. Laboratory-based gait analysis was performed on 1320 gait cycles taken from 20 young, active women walking with three different speeds. Comprehensive anthropometric measurements and descriptive statistics were used to describe spatiotemporal and angular variables at each walking condition. The results demonstrated some significant differences in young, active women walking between different speeds and compared to the literature. This suggests that there is a need to include data from participants with different somatic structures to develop a normative database or limit the database results to a specific population. Detailed linear and angular kinematic variables allow for proper adjustment of parameters depending on the gait speed of people with locomotion disorders.

Critical review of the use and scientific basis of forensic gait analysis

This review summarizes the scientific basis of forensic gait analysis and evaluates its use in the Netherlands, United Kingdom and Denmark, following recent critique on the admission of gait evidence in Canada. A useful forensic feature is (1) measurable, (2) consistent within and (3) different between individuals. Reviewing the academic literature, this article found that (1) forensic gait features can be quantified or observed from surveillance video, but research into accuracy, validity and reliability of these methods is needed; (2) gait is variable within individuals under differing and constant circumstances, with speed having major influence; (3) the discriminative strength of gait features needs more research, although clearly variation exists between individuals. Nevertheless, forensic gait analysis has contributed to several criminal trials in Europe in the past 15 years. The admission of gait evidence differs between courts. The methods are mainly observer-based: multiple gait analysts (independently) assess gait features on video footage of a perpetrator and suspect. Using gait feature databases, likelihood ratios of the hypotheses that the observed individuals have the same or another identity can be calculated. Automated gait recognition algorithms calculate a difference measure between video clips, which is compared with a threshold value derived from a video gait recognition database to indicate likelihood. However, only partly automated algorithms have been used in practice. We argue that the scientific basis of forensic gait analysis is limited. However, gait feature databases enable its use in court for supportive evidence with relatively low evidential value. The recommendations made in this review are (1) to expand knowledge on inter- and intra-subject gait variabilities, discriminative strength and interdependency of gait features, method accuracies, gait feature databases and likelihood ratio estimations; (2) to compare automated and observer-based gait recognition methods; to design (3) an international standard method with known validity, reliability and proficiency tests for analysts; (4) an international standard gait feature data collection method resulting in database(s); (5) (inter)national guidelines for the admission of gait evidence in court; and (6) to decrease the risk for cognitive and contextual bias in forensic gait analysis. This is expected to improve admission of gait evidence in court and judgment of its evidential value. Several ongoing research projects focus on parts of these recommendations.

Systematic Experimental Assessment of a 2D-Motion Sensor to Detect Relative Movement between Residual Limb and Prosthetic Socket

A sensor system for measuring the relative movement between prosthetic socket and residual limb based on a 2D-motion sensor is introduced and thoroughly tested experimentally. The quantitative analysis of test rig evaluation is used to identify advantageous sensor settings and liner configurations. Considering these favorable settings, sensor functionality is quantified to errrel=0.52±1.78%. Advancing to convex measurement surfaces, the sensor shows absolute errors of errabs≤1 mm in an observable measurement scenario. The feasibility of measuring gait-induced relative movement with the proposed 2D-motion sensor is shown via a biomechanical plausibility study. Overall, the findings suggest that the proposed sensor system is suitable for investigating the relative movement between residual limb and prosthetic socket in dynamic gait situations.

Age-related differences in muscle activity patterns during walking in healthy individuals

OBJECTIVE

To examine how muscle activity over the entire gait cycle changes with increasing age.

METHODS

Electromyography data of the erector spinae, rectus femoris, vastus lateralis, biceps femoris, tibialis anterior and gastrocnemius muscles were collected by an instrumented gait analysis during over ground walking in healthy adults aged between 20 and 89 years. Participants were categorized per decade (n = 105, 15 per decade, decades 3-9). Normalized integrated linear envelopes of the electromyographic signal were calculated for one stride. A one way ANOVA using spm1d statistics explored the differences between age groups, followed by a post hoc analysis.

RESULTS

While initiation of decline commenced at the age of 60 for erector spinae and tibialis anterior, age-related changes are most pronounced after the age of 80. Concerning timing of muscle activity, subjects in decade 7-9 had prolonged activity and/or early activity of the erector spinae, vastus lateralis, biceps femoris, tibialis anterior and gastrocnemius compared to other decades. Regarding amplitude of muscle activity, decreased peak amplitudes of the erector spinae, rectus femoris, vastus lateralis and gastrocnemius were observed in decades 7-9 compared to other decades.

CONCLUSION

Both timing and amplitude of muscle activation patterns need to be considered to understand the aging process. Regarding the erector spinae, tibialis anterior and vastus lateralis, a decrease in muscle activation coincides with prolonged activity, compared to the gastrocnemius where decreased muscle activation is associated with early activation.

Influence of normative data's walking speed on the computation of conventional gait indices

The pathology's impact on gait pattern may be overestimated by conventional gait indices (Gillette Gait Index - GGI, Gait Deviation Index - GDI, Gait Profile Score - GPS), since impairments' consequences on kinematics may be amplified by a change in walking speed. The objectives of this study were to evaluate the influence of walking speed on the computation of gait indices and to propose a corrective method to cancel the effects of walking speed. Spatiotemporal parameters and kinematics of fifty-four asymptomatic participants (30 M/24 W, 37.9 ± 13.7 years, 72.8 ± 13.3 kg, 1.74 ± 0.10 m) were collected at four speed conditions (C₁:[0,0.4] m s^-1, C₂:[0.4,0.8] m s^-1, C₃:[0.8,1.2] m s^-1, C₄:spontaneous). Four values of each index were computed for each trial using successively the four conditions as normative data repository. Mean values over all participants were statistically compared (paired t-tests, 95% confidence level). Indices values computed with normative at equivalent walking speed were not statistically different from reference values. Meanwhile, deviations appeared when the walking speed discrepancy between conditions and normative increased. These drifts related to walking speed mismatch have been quantified and fitting functions proposed. A correction was applied to indices. GGI was efficiently adjusted while GDI and GPS remain different from their reference values for C₁ and C₂. Gait indices must be interpreted cautiously in function of the normative data repository's walking speed used for computation. Furthermore, a coupled use of conventional and corrected gait indices could lead to a better comprehension of the contribution of impairments and walking speed on gait deviations and overall gait quality.

Comparison in three dimensional gait kinematics between young and older adults on land and in shallow water

This study investigated in three-dimensional space, firstly whether the aquatic medium and secondly ageing, had any effect on the lower limb's joint angles during aquatic-based gait. Three-dimensional joint kinematics of the lower limb of 51 healthy male participants [25 young group (24.6±4.9 years, 172.1±5.5cm, 69.8±10.3kg) and 26 older group (58.5±5.1 years, 167.9±5.1cm, 70.8±12.1kg)] were quantified during land and shallow water walking. Participants walked at their self-selected comfortable speed in both mediums. The results suggested that the properties of water - hydrodynamic drag, and buoyancy - affected the gait kinematics for both groups. Both age groups used more of their hip flexion in the aquatic environment to help them propel forward instead of using the ankle plantarflexion. The effect of age during the aquatic-based gait was identified in ankle adduction angle and knee abduction/adduction angle at initial contact. Only the older group elicited a significantly smaller ankle adduction angle during the aquatic-based gait when compared to the land-based gait. Only the young group elicited a significantly larger knee abduction/adduction angle at initial contact during the aquatic-based gait when compared to the land-based gait. These findings can facilitate professionals in the area of aquatic rehabilitation to better customise aquatic-based walking exercise programmes to suit their client's specific needs.

Congenital fiber-type disproportion in an ambulatory rehabilitation setting : A case report

Congenital fiber-type disproportion is a rare condition, histologically characterized by a relative type 1 fiber hypotrophy. The main clinical feature is mild-to-severe muscle weakness. In this report, we present the case of a 21-year-old patient with congenital fiber-type disproportion in an outpatient rehabilitative setting to evaluate the feasibility and results of an assessment battery, including bioimpedance analysis (BIA), dynamometry, 3D gait analysis, 6‑min walk test (6MWT), and the timed up and go test (TUG). The patient had a notable decrease in all functional scores. BIA: lean body mass, 38.4 kg (50.2 ± 5.3), body fat, 1.6% (12.4 ± 4.4); hand dynamometry: 18.5 kg left/20.0 kg right (44.8 ± 6.6); walking speed, 58 cm/s (122.7 ± 11.1), step length, 43.0 cm (61.6 ± 3.5); 6MWT: 478.5 m (638 ± 44); TUG: 9.4 s (8.1 ± 1.0). No adverse events were reported. The tests used were easily applicable in clinical routine and well tolerated by our patient.

Effect of Yang-Style Tai Chi on Gait Parameters and Musculoskeletal Flexibility in Healthy Chinese Older Women

The purpose of the present study was to examine the effect of Yang-style Tai chi (TC) on gait parameters and musculoskeletal flexibility in healthy Chinese female adults. Sixty-six female adults aged >65 years were randomly assigned to either an experimental group (67.9 ± 3.2 years of age) receiving three 90-min simplified 24-form TC sessions for eight weeks, or a control group (67.4 ± 2.9 years of age) who maintained their daily lifestyles. All study participants were instructed to perform a selected pace walking for recording gait parameters (stride length, gait speed, swing cycle time, stance phase, and double support times) at both baseline and after the experiment. Low-limb flexibility and range of motion at specific musculoskeletal regions (hip flexion, hip extension, and plantar flexion, as well as anterior and lateral pelvic tilts, pelvic rotation, and joint range of motion (hip, knee, and ankle)) were also assessed in the present study. Multiple separate 2 × 2 Factorial Analysis of Variance (ANOVA) with repeated measures were used to examine the effects of TC on the abovementioned outcomes between baseline and posttest in the two groups. When compared to those in the control group, older female adults who experienced the 8-week Tai chi intervention demonstrated significant improvements in most of the outcome measures. More specifically, positive changes in the TC group were found, including gait parameter (p < 0.001 for all; stride length (1.12 to 1.24, +8.6%), gait speed (1.06 to 1.21, +13.9%), stance phase (66.3 to 61.8, −5.5%), swing phase (33.7 to 38.4, +10.1%), double support time (0.33 to 0.26, −21.1%)), flexibility-related outcomes (hip flexion (90.0 to 91.9, 22.6%, p < 0.0001), single hip flexor (6.0 to 2.0, −61.5%, p = 0.0386), and plantar flexion (41.6 to 49.7, +17.5%, p < 0.0001)), and range of motion (anterior pelvic tilt (9.5 to 6.2, −34.7%, p < 0.0001), lateral pelvic tilt (6.6 to 8.3, +23.8%, p = 0.0102), pelvic rotation (10.3 to 14.7, 28.2%, p < 0.0001), hip range of motion (29.8 to 32.9, +13.5%, p = 0.001), and ankle range of motion (28.0 to 32.6, +11.1%, p < 0.0001)). The present study supports the notion that the practice of TC has a positive effect on healthy older female adults in improving gait parameters and flexibility, counteracting the normal functional degeneration due to age.

Ischiofemoral impingement: defining the lesser trochanter-ischial space

PURPOSE

The purpose of this study was to define changes in the ischial-lesser trochanteric space associated with medial and lateral hip rotation in neutral and 10° of extension and adduction.

METHODS

Twenty-five hip joints from 14 embalmed cadavers (7 males and 7 females) were used for this study. The pelvic region of each cadaver was skeletonized, and the hip capsule released distally. With the hip joint in 0° flexion-extension/abduction-adduction, the distance between the lesser trochanter and ischium was measured in: neutral rotation, 40° medial rotation, and 60° lateral rotation. A one-way ANOVA with post hoc analysis determined the difference in the ischiofemoral space in these three positions. An additional position was then tested by laterally rotating the femur with the hip joint positioned in 10° extension and adduction.

RESULTS

The average distance between the lesser trochanter and ischium was different (p < .0005) in neutral rotation, 40° medial rotation, and 60° lateral rotation at 2.8 cm (SD 1.1), 4.3 cm (SD 1.2), and 1.4 cm (SD 0.7), respectively. With the hip joint laterally rotated from a starting position of 10° extension and adduction, 21 of 25 (84 %) hips made contact between the lesser trochanter and ischium at an average position of 29° (SD 20) of lateral rotation.

CONCLUSIONS

The lesser trochanter is closest to the ischium in lateral rotation and is furthest away in medial rotation when the hip is in neutral flexion-extension/abduction-adduction. The lesser trochanter approximates the ischium when the hip is laterally rotated in 10° extension and adduction. The information gained through this investigation helps to define the pathomechanics associated with ischiofemoral impingement and validate clinical tests to diagnose ischiofemoral impingement.

Validity and test-retest reliability of the Stride Analyzer in people with knee osteoarthritis

INTRODUCTION

Subjects with knee osteoarthritis walk differently compared to healthy subjects. Managing these gait alterations has been proven effective for reducing pain and increasing function. The Stride Analyzer is a low cost gait analysis tool but its clinimetric properties have not been investigated yet in subjects with symptomatic knee osteoarthritis. The aim of this study was to investigate the reliability and validity of the SA compared with the Gold standard (Vicon) in persons with knee OA.

METHODS

Fifteen subjects with symptomatic knee osteoarthritis were instructed to walk at a self-selected speed in a gait laboratory. Temporospatial (TS) gait parameters were recorded simultaneously by the Stride Analyzer and by a 16-camera-infrared optoelectronic motion capturing system (Vicon). Validity and test-retest reliability of the Stride Analyzer were examined by Bland-Altman plots, intra-class correlation coefficients (ICC) and the standard error of measurement (SEM).

RESULTS

Test-retest analyses showed good agreement for all TS parameters with ICC values ranging from 0.805 (single limb support right) to 0.949 (velocity) and SEM% values ranging from 0.78% (stance phase right (% of gait cycle)) to 4.52% (double limb support right (% of gait cycle)). Good agreement between Stride Analyzer and Vicon was found for the following TS parameters: velocity (z=1.01), cadence (z=-0.85), stride length (z=1.63) and gait cycle (z=0.86). All other gait parameters showed lower ICC values (<0.689).

INTERPRETATION

Our results suggest that the Stride Analyzer can be used in the clinical field to perform gait analysis in subjects with symptomatic knee osteoarthritis.

A pilot study of biomechanical assessment before and after an integrative training program for adolescents with juvenile fibromyalgia

BACKGROUND

Adolescents with juvenile fibromyalgia (JFM) tend to be very sedentary and avoid participation in physical activity. A prior study suggested that JFM patients show altered biomechanics compared to healthy adolescents which may make them more prone to pain/injury during exercise. A new intervention combining well established cognitive behavioral therapy (CBT) techniques with specialized neuromuscular exercise -Fibromyalgia Integrative Training for Teens (FIT Teens) was developed and shown to be promising in improving functioning in adolescents with JFM. In contrast to traditional exercise programs such as aerobic or resistance training, neuromuscular training is a tailored approach which targets gait, posture, balance and movement mechanics which form the foundation for safe exercise participation with reduced risk for injury or pain (and hence more tolerable by JFM patients). The aim of this pilot feasibility study was to establish whether objective biomechanical assessment including sophisticated 3-D motion analysis would be useful in measuring improvements in strength, balance, gait, and functional performance after participation in the 8-week FIT Teens program.

METHODS

Eleven female participants with JFM (ages 12-18 years) completed pre- and post-treatment assessments of biomechanics, including walking gait analysis, lower extremity strength assessment, functional performance, and dynamic postural stability.

RESULTS

Descriptive data indicated that mechanics of walking gait and functional performance appeared to improve after treatment. Hip abduction strength and dynamic postural control also demonstrated improvements bilaterally.

CONCLUSIONS

Overall, the results of this pilot study offer initial evidence for the utility of biomechanical assessment to objectively demonstrate observable changes in biomechanical performance after an integrated training intervention for youth with JFM. If replicated in larger controlled studies, findings would suggest that through the FIT Teens intervention, adolescents with JFM can progress towards normalized strength and biomechanics, which may enhance their ability to engage in physical exercise.

Quantitative assessment of retropulsion of the hip, excessive hip external rotation, and excessive lateral shift of the trunk over the unaffected side in hemiplegia using three-dimensional treadmill gait analysis

BACKGROUND

Gait assessment is important to determine the most effective strategy to regain gait function during stroke rehabilitation. To understand the mechanisms that cause abnormal gait patterns, it is useful to objectively identify and quantify the abnormal gait patterns. Objective assessment also helps evaluate the efficacy of treatments and can be used to provide suggestions for treatment.

OBJECTIVE

To evaluate the validity of quantitative indices for retropulsion of the hip, excessive hip external rotation, and excessive lateral shift of the trunk over the unaffected side in hemiplegic patients.

METHODS

Forty-six healthy control subjects and 112 hemiplegic patients participated. From the 112 patients, 50 patients were selected into each abnormal gait pattern with some overlap. Participants were instructed to walk on a treadmill and were recorded using a three-dimensional motion analysis system. An index to quantify each of the three abnormal gait patterns was calculated from the three-dimensional coordinate data. The index values of patients were compared with those of healthy subjects and with the results of observational gait assessment by three physical therapists with expertise in gait analysis.

RESULTS

Strong correlation was observed between the index value and the median observational rating for all three abnormal gait patterns (-0.56 to -0.74). Most of the patients with an abnormal gait pattern had a higher index value than the healthy subjects.

CONCLUSIONS

The proposed indices are useful for clinical gait analysis. Our results encourage a more detailed analysis of hemiplegic gait using a motion analysis system.

The effects of the length of rain boots on balance during treadmill walking

[Purpose] Effects of muscle fatigue on lower-extremity balance were evaluated in 12 healthy young women in their 20s while they walked on a treadmill wearing rain boots of different lengths. [Methods] The rain boots were divided into three groups based on the shaft length (Long, Middle, Short). Romberg's test was applied and limits of stability were measured before and after treadmill walking. [Results] Romberg's test showed a significant main effect for time. There were significant differences between the center of gravity area, length, and velocity when the eyes were open and the center of gravity length, velocity, and length/cm(2) when the eyes were closed. Changes in the limits of stability also showed a significant main effect of time. There were significant differences in pre-test and post-test values in the left, right, forward, and total directions. [Conclusion] It was found that muscle fatigue in the lower extremities generated by walking in rain boots affected the joints and the adjuster muscles, depending on shaft lengths. Compensation due to visual feedback and the length of the boot shaft affected movement of the distal joints, resulting in a reduced ability to balance.