Side to side kinematic gait differences within patients and spatiotemporal and kinematic gait differences between patients with severe knee osteoarthritis and controls measured with inertial sensors

BackgroundKinematic changes associated with knee osteoarthritis (OA) have been traditionally measured with camera-based gait analysis. Lately, inertial sensors have become popular for gait analysis with the advantage of being less time consuming and not requiring a dedicated laboratory.Research questionDo spatiotemporal and discrete kinematic gait parameters measured with the inertial sensor system RehaGait® differ between the affected and unaffected side in patients with unilateral knee OA and between patients with severe knee OA and asymptomatic control subjects? Do these differences have a similar magnitude as those reported in the literature?MethodsTwenty-two patients with unilateral knee OA scheduled for total knee replacement and 46 age matched control subjects were included in this study. Spatiotemporal parameters and sagittal kinematics at the hip, knee, and ankle joint were measured using the RehaGait® system while walking at a self-selected speed for a distance of 20 m and compared between groups.ResultsPatients with knee OA had slower walking speed, longer stride duration, shorter stride length and lower cadence (P < 0.001). Peak knee flexion during stance and swing was lower in the affected than the unaffected leg (-4.8° and -6.1°; P < 0.01). Peak knee flexion during stance and swing (-5.2° and -8.8°; P < 0.01) and knee range of motion during loading response and swing (-3.6° and -4.4°; P < 0.01) were lower than in the control group.SignificanceThese side to side differences within patients and differences between patients with knee OA and control subjects agree with known gait alterations measured with camera-based systems. The RehaGait® inertial sensor system can detect gait alterations in patients with knee OA and is suitable for gait analysis in a clinical environment.     

The effect of a dual task on gait speed in community dwelling older adults: A systematic review and meta-analysis

Background and purposeReduced walking speed in older adults is associated with adverse health outcomes. This review aims to examine the effect of a cognitive dual-task on the gait speed of community-dwelling older adults with no significant pathology affecting gait.Data sources and study selectionElectronic database searches were performed in, Web of Science, PubMed, SCOPUS, Embase and psychINFO. Eligibility and methodological quality was assessed by two independent reviewers. The effect size on gait speed was measured as the raw mean difference (95% confidence interval) between single and dual-task performance. Pooled estimates of the overall effect were computed using a random effects method and forest plots generated.Data extraction and data synthesis22 studies (27 data sets) with a population of 3728 were reviewed and pooled for meta-analysis. The mean walking speed of participants included in all studies was >1.0 m/s and all studies reported the effect of a cognitive dual-task on gait speed. Sub-analysis examined the effect of type of cognitive task (mental-tracking vs. verbal-fluency). Mean single-task gait speed was 1.21 (0.13) m/s, the addition of a dual-task reduced speed by 0.19 m/s to 1.02 (0.16) m/s (p < 0.00001), both mental-tracking and verbal-fluency tasks resulted in significant reduction in gait speed.Limitations and conclusionThe cross-sectional design of the studies made quality assessment difficult. Despite efforts, high heterogeneity remained, possibly due to participant characteristics and testing protocols. This meta-analysis shows that in community-dwelling older adults, the addition of a dual-task significantly reduces gait speed and may indicate the value of including dual-task walking as part of the standard clinical assessment of older people.     

Reliability of inertial sensor based spatiotemporal gait parameters for short walking bouts in community dwelling older adults

BackgroundWhen performing quantitative analysis of gait in older adults we need to strike a balance between capturing sufficient data for reliable measurement and avoiding issues such as fatigue. The optimal bout duration is that which contains sufficient gait cycles to enable a reliable and representative estimate of gait performance.Research questionHow does the number of gait cycles in a walking bout influence reliability of spatiotemporal gait parameters measured using body-worn inertial sensors in a cohort of community dwelling older adults?MethodsOne hundred and fifteen (115) community dwelling older adults executed three 30-metre walk trials in a single measurement session. Bilateral gait data were collected using two inertial sensors attached to each participant’s right and left shank, and gait events detected from the medio-lateral angular velocity signal. The number of gait cycles selected from each walking trial was varied from 3 to 16. Intraclass correlation coefficients (ICC(2,k)) were calculated to evaluate the reliability of each spatiotemporal gait parameter according to the number of gait cycles included in the analysis.ResultsThe specified algorithm and the clipping procedure for extracting short bouts of gait data seem appropriate for assessing older adults, providing reliable spatiotemporal measures from three gait cycles (three strides per leg) and good reliability for most parameters describing gait variability and gait asymmetry after six gait cycles (six strides per leg).SignificanceA combination of using bilateral sensor data and adaptive thresholds for gait event detection enable reliable measures of spatiotemporal gait parameters over short walking bouts (minimum six gait cycles) in community dwelling older adults. This opens new possibilities in the use of wearable sensors in gait assessment based on short walking tasks. We recommend the number of gait cycles should be reported along with the calculated measures as reference values.     

Trunk sway during walking among older adults: Norms and correlation with gait velocity

The aim of this study was to establish quantitative norms for trunk sway during walking for older male and female ambulatory adults at different age groups (65–70, 71–75, 76–80, ≥81). We also assessed the relationship between dynamic trunk sway and gait velocity in older individuals with clinically normal or abnormal gaits. Trunk sway in medio-lateral (roll) and antero-posterior (pitch) planes was measured using a body-mounted gyroscope (SwayStar) during walking on a 4.5 m long instrumented walkway. Of the 284 older adults (mean age 76.8, 54.6% women) in this sample, the mean ± SD value of roll and pitch angles were 6.0 ± 2.0° and 6.7 ± 2.2° respectively. Older women showed significantly greater trunk sway in both roll and pitch angles than older men (p < 0.01). In both men and women, there was no significant association of roll angle with age although gait velocity decreased with increasing age. The relationship between roll angle and gait velocity was U-shaped for the overall sample. Among the subgroup with clinically normal gait, increased roll angle was associated with increased gait velocity (p < 0.001). However, there was no significant relationship between roll angle and gait velocity among the subgroup with abnormal gait. Therefore, the relationship between medio-lateral trunk sway and gait velocity differs depending on whether gait is clinically normal.We conclude that trunk sway during walking should be interpreted with consideration of both gait velocity and presence of gait abnormality in older adults.     

Trunk sway during walking among older adults: Norms and correlation with gait velocity

The aim of this study was to establish quantitative norms for trunk sway during walking for older male and female ambulatory adults at different age groups (65–70, 71–75, 76–80, ≥81). We also assessed the relationship between dynamic trunk sway and gait velocity in older individuals with clinically normal or abnormal gaits. Trunk sway in medio-lateral (roll) and antero-posterior (pitch) planes was measured using a body-mounted gyroscope (SwayStar) during walking on a 4.5 m long instrumented walkway. Of the 284 older adults (mean age 76.8, 54.6% women) in this sample, the mean ± SD value of roll and pitch angles were 6.0 ± 2.0° and 6.7 ± 2.2° respectively. Older women showed significantly greater trunk sway in both roll and pitch angles than older men (p < 0.01). In both men and women, there was no significant association of roll angle with age although gait velocity decreased with increasing age. The relationship between roll angle and gait velocity was U-shaped for the overall sample. Among the subgroup with clinically normal gait, increased roll angle was associated with increased gait velocity (p < 0.001). However, there was no significant relationship between roll angle and gait velocity among the subgroup with abnormal gait. Therefore, the relationship between medio-lateral trunk sway and gait velocity differs depending on whether gait is clinically normal.We conclude that trunk sway during walking should be interpreted with consideration of both gait velocity and presence of gait abnormality in older adults.     

Benefits of multi-session balance and gait training with multi-modal biofeedback in healthy older adults

Real-time balance-relevant biofeedback from a wearable sensor can improve balance in many patient populations, however, it is unknown if balance training with biofeedback has lasting benefits for healthy older adults once training is completed and biofeedback removed. This study was designed to determine if multi-session balance training with and without biofeedback leads to changes in balance performance in healthy older adults; and if changes persist after training. 36 participants (age 60–88) were randomly divided into two groups. Both groups trained on seven stance and gait tasks for 2 consecutive weeks (3×/week) while trunk angular sway and task duration were monitored. One group received real-time multi-modal biofeedback of trunk sway and a control group trained without biofeedback. Training effects were assessed at the last training session, with biofeedback available to the feedback group. Post-training effects (without biofeedback) were assessed immediately after, 1-week, and 1-month post-training. Both groups demonstrated training effects; participants swayed less when standing on foam with eyes closed (EC), maintained tandem-stance EC longer, and completed 8 tandem-steps EC faster and with less sway at the last training session. Changes in sway and duration, indicative of faster walking, were also observed after training for other gait tasks. While changes in walking speed persisted post-training, few other post-training effects were observed. These data suggest there is little added benefit to balance training with biofeedback, beyond training without, in healthy older adults. However, transient use of wearable balance biofeedback systems as balance aides remains beneficial for challenging balance situations and some clinical populations.     

A consensus guide to using functional near-infrared spectroscopy in posture and gait research

BackgroundFunctional near-infrared spectroscopy (fNIRS) is increasingly used in the field of posture and gait to investigate patterns of cortical brain activation while people move freely. fNIRS methods, analysis and reporting of data vary greatly across studies which in turn can limit the replication of research, interpretation of findings and comparison across works.Research question and methodsConsidering these issues, we propose a set of practical recommendations for the conduct and reporting of fNIRS studies in posture and gait, acknowledging specific challenges related to clinical groups with posture and gait disorders.ResultsOur paper is organized around three main sections: 1) hardware set up and study protocols, 2) artefact removal and data processing and, 3) outcome measures, validity and reliability; it is supplemented with a detailed checklist.SignificanceThis paper was written by a core group of members of the International Society for Posture and Gait Research and posture and gait researchers, all experienced in fNIRS research, with the intent of assisting the research community to lead innovative and impactful fNIRS studies in the field of posture and gait, whilst ensuring standardization of research.     

Agreement and consistency of five different clinical gait analysis systems in the assessment of spatiotemporal gait parameters

BackgroundMeasuring gait function has become an essential tool in the assessment of mobility in aging populations for both, clinicians and researchers. A variety of systems exist that assess gait parameters such as gait cycle time, gait speed or duration of relative gait phases. Due to different measurement principles such as inertial or pressure sensors, accurate detection of spatiotemporal events may vary between systems.Research questionTo compare the absolute agreement and consistency in spatiotemporal gait parameters among five different clinical gait analysis systems using different sensor technologies.MethodsWe compared two devices using inertial sensors (GaitUp & Mobility Lab), two devices using pressure sensor systems (GAITRite & Zebris) as well as one optical system (OptoGait). Twelve older adults walked at self-selected speed through a walkway integrating all of the above systems. Basic spatiotemporal parameters (gait cycle time, cadence, gait speed and stride length) as well as measures of relative phase (stance phase, swing phase, double stance phase, single limb support) were extracted from all systems. We used Intraclass Correlation Coefficients as measures of agreement and consistency.ResultsHigh agreement and consistency between all systems was found for basic spatiotemporal parameters, whereas parameters of relative phase showed poorer agreement and consistency. Overground measurement (GAITRite & OptoGait) showed generally higher agreement with each other as compared to inertial sensor-based systems.SignificanceOur results indicate that accurate detection of both, the heel-strike and toe-off event are crucial for reliable results. Systematic errors in the detection of one or both events may only have a small impact on basic spatiotemporal outcomes as errors remain consistent from step to step. Relative phase parameters on the other hand may be affected to a much larger extent as these differences lead to a systematic increase or reduction of relative phase durations.     

25 years of lower limb joint kinematics by using inertial and magnetic sensors: A review of methodological approaches

Joint kinematics is typically limited to the laboratory environment, and the restricted volume of capture may vitiate the execution of the motor tasks under analysis. Conversely, clinicians often require the analysis of motor acts in non-standard environments and for long periods of time, such as in ambulatory settings or during daily life activities. The miniaturisation of motion sensors and electronic components, generally associated with wireless communications technology, has opened up a new perspective: movement analysis can be carried out outside the laboratory and at a relatively lower cost. Wearable inertial measurement units (embedding 3D accelerometers and gyroscopes), eventually associated with magnetometers, allow one to estimate segment orientation and joint angular kinematics by exploiting the laws governing the motion of a rotating rigid body. The first study which formalised the problem of the estimate of joint kinematics using inertial sensors dates back to 1990. Since then, a variety of methods have been presented over the past 25 years for the estimate of 2D and 3D joint kinematics by using inertial and magnetic sensors. The aim of the present review is to describe these approaches from a purely methodological point of view to provide the reader with a comprehensive understanding of all the instrumental, computational and methodological issues related to the estimate of joint kinematics when using such sensor technology.     

Manipulating walking path configuration influences gait variability and six-minute walk test outcomes in older and younger adults

This study determined whether manipulations to walking path configuration influenced six-minute walk test (6MWT) outcomes and assessed how gait variability changes over the duration of the 6MWT in different walking path configurations. Healthy older (ODR) and younger (YNG) (n = 24) adults completed familiarisation trials and five randomly ordered experimental trials of the 6MWT with walking configurations of; 5, 10 and 15 m straight lines, a 6 m by 3 m rectangle (RECT), and a figure of eight (FIG8). Six-minute walk distance (6MWD) and walking speed (m.s⁻¹) were recorded for all trials and the stride count recorded for experimental trials. Reflective markers were attached to the sacrum and feet with kinematic data recorded at 100 Hz by a nine-camera motion capture system for 5 m, 15 m and FIG8 trials, in order to calculate variability in stride and step length, stride width, stride and step time and double limb support time. Walking speeds and 6MWD were greatest in the 15 m and FIG8 experimental trials in both groups (p < 0.01). Step length and stride width variability were consistent over the 6MWT duration but greater in the 5 m trial vs. the 15 m and FIG8 trials (p < 0.05). Stride and step time and double limb support time variability all reduced between 10 and 30 strides (p < 0.01). Stride and step time variability were greater in the 5 m vs. 15 m and FIG8 trials (p < 0.01). Increasing uninterrupted gait and walking path length results in improved 6MWT outcomes and decreased gait variability in older and younger adults.     

A systematic review of gait analysis methods based on inertial sensors and adaptive algorithms

The conventional methods to assess human gait are either expensive or complex to be applied regularly in clinical practice. To reduce the cost and simplify the evaluation, inertial sensors and adaptive algorithms have been utilized, respectively. This paper aims to summarize studies that applied adaptive also called artificial intelligence (AI) algorithms to gait analysis based on inertial sensor data, verifying if they can support the clinical evaluation. Articles were identified through searches of the main databases, which were encompassed from 1968 to October 2016. We have identified 22 studies that met the inclusion criteria. The included papers were analyzed due to their data acquisition and processing methods with specific questionnaires. Concerning the data acquisition, the mean score is 6.1 ± 1.62, what implies that 13 of 22 papers failed to report relevant outcomes. The quality assessment of AI algorithms presents an above-average rating (8.2 ± 1.84). Therefore, AI algorithms seem to be able to support gait analysis based on inertial sensor data. Further research, however, is necessary to enhance and standardize the application in patients, since most of the studies used distinct methods to evaluate healthy subjects.     

Utility of an obstacle-crossing test to classify future fallers and non-fallers at hospital discharge after stroke: A pilot study

BackgroundExisting clinical assessments of balance and functional mobility have poor predictive accuracy for prospectively identifying post-stroke fallers, which may be due to a lack of ecological complexity that is typical of community-based fall incidents.Research questionDoes an obstacle-crossing test at hospital discharge predict fall status of ambulatory stroke survivors 3 months after discharge?MethodsAmbulatory stroke survivors being discharged home completed an obstacle-crossing test at hospital discharge. Falls were tracked prospectively for 3 months after discharge. Logistic regression examined the relationship between obstacle-crossing at discharge (pass/fail) and fall status (faller/non-faller) at 3 months post discharge.Results45 participants had discharge obstacle test and 3-month fall data. 21 (47 %) participants experienced at least one fall during follow-up, with 52 % of the falls occurring within the first month after discharge. Of the 21 fallers, 14 failed the obstacle-crossing test (67 % sensitivity). Among the 24 non-fallers, 20 passed the obstacle-crossing test (83 % specificity). The area under the receiver operating characteristic curve was 0.75 (95 % CI 0.60–0.90). Individuals who failed the obstacle-crossing test were 10.00 (95 % CI: 2.45–40.78) times more likely to fall in the first 3 months after discharge. The unadjusted logistic regression model correctly classified 76 % of the subjects. After adjusting for age, sex, days post stroke, and post-stroke disability, the odds ratio remained significant at 6.93 (95 % CI: 1.01–47.52) and correctly classified 79.5% of the participants.SignificanceThe obstacle-crossing test may be a useful discharge assessment to identify ambulatory stroke survivors being discharged home who are likely to fall in the first 3 months post discharge. Modifications to improve the obstacle-crossing test sensitivity should be explored further.     

Comparable walking gait performance during executive and non-executive cognitive dual-tasks in chronic stroke: A pilot study

BackgroundFalls are a serious problem among stroke survivors due to subsequent injuries, recovery setbacks, dependence, and mortality. A growing body of dual-task (DT) studies suggests a role of executive functions in gait control and falls, particularly in subacute stroke. However, few studies have compared distinct executive and non-executive tasks, nor their effects on chronic stroke gait. Research question: The purpose of this cross-sectional study was to compare the effects of distinct working memory (2-back) and inhibition (Stroop) tasks on walking gait performance in chronic stroke survivors.MethodsA pilot sample of chronic stroke survivors (n = 11, 8 males, mean age = 70.91, 6-12months post-stroke event) and age-matched healthy controls (n = 13, 4 male; mean age = 68.46) were tested. Gait performance (speed, stride time, stride time variability, stride length and stride length variability) was measured using 2 wireless inertial measurement sensors under 4 walking conditions: 1) preferred walking (single-task: ST), 2) walking with a 2-back DT, 3) walking with a Stroop DT, and 4) walking with a non-executive motor response DT. The secondary tasks were also carried out in both ST (seated) and DT conditions, to examine bidirectional effects.ResultsWhile the stroke survivor sample had a slower gait speed across conditions and tasks, there were no significant differences between the groups [F(1, 22) = 1.13, p =.299, η²p = .049] on the spatial or temporal gait characteristics recorded: gait performance was maintained during executive and non-executive DTs. In addition, we did not find a significant effect of group on cognitive task performance (all p > .052). However, we observed a cost in accuracy on the 2-back DT for both groups, suggesting resource overlap and greater cognitive load (all t > 19.72, all p < .001).SignificanceOur gait data contradict previous studies evidencing impaired gait post-stroke, suggesting functional recovery in this chronic stroke sample.     

A pilot study of physical activity and sedentary behavior distribution patterns in older women

The study aims were to investigate free-living physical activity and sedentary behavior distribution patterns in a group of older women, and assess the cross-sectional associations with body mass index (BMI).Eleven older women (mean (SD) age: 77 (9) yrs) wore custom-built activity monitors, each containing a tri-axial accelerometer (±16 g, 100 Hz), on the waist and ankle for lab-based walking trials and 4 days in free-living. Daily active time, step counts, cadence, and sedentary break number were estimated from acceleration data. The sedentary bout length distribution and sedentary time accumulation pattern, using the Gini index, were investigated. Associations of the parameters’ total daily values and coefficients of variation (CVs) of their hourly values with BMI were assessed using linear regression.The algorithm demonstrated median sensitivity, positive predictive value, and agreement values >98% and <1% mean error in cadence calculations with video identification during lab trials. Participants’ sedentary bouts were found to be power law distributed with 56% of their sedentary time occurring in 20 min bouts or longer. Meaningful associations were detectable in the relationships of total active time, step count, sedentary break number and their CVs with BMI. Active time and step counts had moderate negative associations with BMI while sedentary break number had a strong negative association. Active time, step count and sedentary break number CVs also had strong positive associations with BMI.The results highlight the importance of measuring sedentary behavior and suggest a more even distribution of physical activity throughout the day is associated with lower BMI.     

Foot and ankle biomechanics during walking in older adults: A systematic review and meta-analysis of observational studies

BackgroundThe foot and ankle complex undergoes significant structural and functional changes with advancing age.Research questionThe objective of this systematic review and meta-analysis was to synthesize and critique the research literature pertaining to foot and ankle biomechanics while walking in young and older adults.MethodsElectronic databases (Web of Science, PubMed, Scopus and Embase) were searched from inception to April 2019 for cross-sectional studies which compared kinematics, kinetics and plantar pressure differences between young and older adults. Screening and data extraction were performed by two independent assessors, with disagreements resolved by consensus.ResultsA total of 39 articles underwent full-text screening, and 19 articles met the inclusion criteria and were included. Meta-analysis showed that older adults had less ankle joint plantar flexion (5 studies; weighted mean difference [WMD]: −5.15; 95 %CI: −6.47 to −3.83; P < 0.001) and less ankle joint power generation (6 studies; standardized mean difference [SMD]: −0.62; 95 %CI: −0.82 to −0.41; P < 0.001) during propulsion compared to young adults. These differences persisted in subgroup analyses comparing different walking speeds. Plantar pressure findings were highly variable due to differences in data collection protocols and meta-analysis was not possible.SignificanceOlder adults have unique foot and ankle kinematics and kinetics during walking characterized by reduced ankle joint plantarflexion and power generation during propulsion.     

Plantarflexor passive-elastic properties related to BMI and walking performance in older women

The objective of this study was to examine the influence of BMI on the passive-elastic properties of the ankle plantarflexors in older women. Twenty-three women, 65–80 yr, were separated into normal weight (NW, BMI < 25.0 kg m⁻², n = 11) and overweight-obese (OW, BMI ≥ 25.0 kg m⁻², n = 12) groups. Resistive torque of the ankle plantarflexors was recorded on an isokinetic dynamometer by passively moving the ankle into dorsiflexion. Stiffness, work absorption, and hysteresis were calculated across an ankle dorsiflexion angle of 10–15°. Maximal plantarflexor strength was assessed, then participants walked at maximal speed on an instrumented gait analysis treadmill while muscle activation (EMG) was recorded. Plantarflexor stiffness was 34% lower in OW (26.4 ± 12.7 Nm rad⁻¹) than NW (40.0 ± 15.7 Nm rad⁻¹, p = 0.032). Neither work absorption nor hysteresis were different between OW and NW. Stiffness per kg was positively correlated to strength (r = 0.66, p < 0.001), peak vertical ground reaction force during walking (r = 0.72, p < 0.001), weight acceptance rate of force (r = 0.51, p = 0.007), push-off rate of force (r = 0.41, p = 0.026), maximal speed (r = 0.61, p = 0.001), and inversely correlated to BMI (r = −0.61, p = 0.001), and peak plantarflexor EMG (r = −0.40, p = 0.046). Older women who are OW have low plantarflexor stiffness, which may limit propulsive forces during walking and necessitate greater muscle activation for active force generation.     

Quantification of the validity and reliability of sprint performance metrics computed using inertial sensors: A systematic review

BackgroundWearable inertial sensors enable sprinting to be biomechanically evaluated in a simple and time efficient manner outside of a laboratory setting.Research Question: Are wearable inertial sensors a valid and reliable method for collecting and measuring sprint performance variables compared to referenced systems?MethodsPubMed, SPORTDiscus, and Web of Science were searched using the Boolean phrases: ((run* OR sprinting OR sprint*) AND (IMU OR inertial sensor OR wearable sensor OR accelerometer OR gyroscope) AND (valid* OR reliabil*)). Articles with injury-free subjects of any age, sex or activity level were included.ResultsFifteen studies met the inclusion criteria and were retained for analysis. In summary, higher Intra-class correlation [ICC] or Pearson correlation coefficients (r) were observed for contact time (ICC ≥ 0.80, r ≥ 0.99), trunk angular displacement (r ≥ 0.99), vertical and horizontal force (ICC ≥ 0.88), and theoretical measures of force, velocity and power (r ≥ 0.81). Low coefficient of variation (CV) were found in peak velocity (≤ 1%), average velocity (≤ 3%), and contact time (≤ 3%,). Average and peak velocity, and resultant forces, were found to have a wide range of r (0.32-0.92) and CVs (0.78–20.2%). The lowest r (-0.24 to 0.49) and highest CVs (15–22.4%) were noted for average acceleration, crania-caudal force, instantaneous forces, medio-lateral ground reaction forces, and rate of decrease in ratio of forces.SignificanceDue to a wide range of methodological differences, a clear understanding of the validity and reliability of different inertial sensors for the analysis of sprinting has yet to be established. Future research into the sensor’s placement, attachment method and sampling frequency are among several factors that need further investigation.     

The relationship between forward head posture,postural control and gait: A systematic review

BackgroundForward head posture (FHP) is a common postural deviation. An increasing number of studies have reported that people with FHP present with impaired postural control and gait; however, there is conflicting evidence. A systematic review focusing on these relationships has been unavailable to date.Research questionIs there a relationship between FHP, postural control and gait?MethodsThis systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement (PROSPERO ID: CRD42021231908). Web of Science, PubMed, Scopus, and CINAHL Plus (via EBSCO) were systematically searched, and a manual search was performed using the reference lists of included studies. Eligible studies included observational studies addressing the relationship between FHP, postural control and/or gait. Quality assessment was conducted using the Joanna Briggs Institute Critical Appraisal Checklist for Cross-Sectional Studies.ResultsNineteen studies were selected for this review. Consistent evidence supported that people with FHP had significant alterations in limits of stability (n = 3), performance-based balance (n = 3), and cervical proprioception (n = 4). Controversial evidence existed for a relationship of FHP with static balance (n = 4) and postural stability control (n = 4). Limited evidence existed to support an alteration in gait and vestibular function. Three studies on induced FHP consistently identified no reduced postural control.SignificanceCurrent evidence supports an association between FHP and a detrimental alteration in limits of stability, performance-based balance, and cervical proprioception. Instead of simply indicating impaired overall balance, the findings of this review indicate that a reduction in specific aspects of the postural control requires to be clarified in clinical evaluation for individuals with FHP, which would facilitate the planning and application of appropriate interventions to prevent dysfunctions and disability.     

Lower limb muscle activation in response to balance-perturbed tasks during walking in older adults: A systematic review

BackgroundDeclines in muscular function may hinder our ability to properly respond balance perturbations during walking. Examining age-related differences in muscle activation during balance-perturbed walking could be an important summary of literature to guide future clinical or scientific research.Research questionAre there differences in lower limb muscle activation between young and older adults when responding to balance perturbations during walking?MethodsA literature search was conducted in October 2020 to identify relevant articles using Pubmed, Scopus, Web of Science, Ovid EMBASE, and CINAHL. Inclusion criteria were defined to identify studies investigating lower limb muscle activation in healthy older adults during balance-perturbed walking. Data extraction was independently performed by both authors. Outcome measures included key findings of lower limb muscle activations during walking and balance-related tasks (e.g. multidirectional perturbations, different speeds, cognitive tasks, slippery/slopes, and obstacles).ResultsThis article reviewed fourteen studies including 230 older adults (age: 70 ± 4.5, females: 124 [53.9%]) and 230 young adults (age: 23 ± 2.0, females: 113 [49.1%]). The overall quality of included studies was fair, with a mean score of 76%. Twelve lower limb muscles were assessed during balance-perturbed walking. All studies reported electromyographic measurements, including magnitude, timing, co-contraction indices, and variability of activation.SignificanceCompared to young adults, older adults demonstrated different adaptations in lower limb muscle activation during balance-perturbed walking. Co-contraction of ankle and knee joint muscles had more conclusive results, with the majority reporting an increased co-contraction in older adults, especially when balance is perturbed by a physical task. These data suggest that coordination between agonist and antagonist muscles is important to provide necessary stabilization during balance-perturbed walking.