Mohammad Al-Amri | Cardiff University (original) (raw)

Papers by Mohammad Al-Amri

Introduction and Objectives: Negotiating obstacles is a complex motor-control task that is descri... more Introduction and Objectives: Negotiating obstacles is a complex motor-control task that is described as the most common cause of falling during walking [1-2]. Successful obstacle negotiation may be compromised in individuals with gait problems [3]. Understanding how individuals negotiate obstacles while maintaining a stable and safe walking pattern is therefore important for development of interventions based on motor learning. Virtual reality can provide controlled stimuli in a meaningful, safe environment for rehabilitation and motor-control assessment [4]. This study aimed to explore how healthy individuals respond to different presentations of virtual obstacles (VOs). The expectation was that the similar changes would occur in their motor-control as seen for real-world obstacle clearance. Changes in average values of gait parameters were used as performance indicators whereas changes in variability of these parameters were used to indicate altered motor-control. Methods: Twenty ...

Gait analysis can be used to predict health status in the elderly (1). Gait is no longer postulat... more Gait analysis can be used to predict health status in the elderly (1). Gait is no longer postulated as a totally automated motor task. It requires multiple executive function processes to utilise safe and efficient gait (2). With advanced age, executive function declines, which is linked to an increase in gait variability and fall-risk. Dual-task paradigms have been introduced to explore the automaticity of gait by challenging inhibition and/or attention (i.e. executive function). The utility of using dual-tasking has become more evident (2). However, the great variability of the dual-tasking paradigms limits its use in clinical gait assessment. There is also a lack of evidence for the consistency of dual-task effects upon gait performance. This may be due to the limited number of consecutive strides included during over-ground walking and effects of treadmill’s speed on gait patterns (3). The aim of this study was, therefore, to explore the effect of an inhibition response task on ...

The aim of this preliminary study was to explore the effects of two types of augmented feedback o... more The aim of this preliminary study was to explore the effects of two types of augmented feedback on the strategy used by healthy participants and patients with knee osteoarthritis (OA) to perform a double-leg squat. Seven patients with knee OA and seven healthy participants performed three sets of eight double-leg squats: one without feedback, one with real-time kinematic feedback and one with real-time kinetic feedback. Kinematic and kinetic outcome measures (peak knee flexion angle, peak knee extensor moment, and symmetry of the support knee moment between the injured and non-injured knees) demonstrate the potential influence of real-time kinetic feedback on the motor strategy used to perform a double-leg squat in both groups. This feedback could be used to develop more efficient and effective motor strategies for squatting in patients with knee OA and further evaluation is warranted.

Alterations in knee adduction moment (KAM) has been suggested as a surrogate measure of medial co... more Alterations in knee adduction moment (KAM) has been suggested as a surrogate measure of medial compartment (1). It has two peaks; the first peak has been correlated with the progress of knee osteoarthritis (OA) that is more common in elderly population (2). Individuals with OA suffer to the limit of functional mobility including walking. Walking involves cognitive processes related to planning and performing actions. With advancing age, reduction in the cognitive functions related to walking has been noted (3). As OA is an age-related condition, it is therefore, necessary to consider OA gait assessment whilst individuals performing additional cognitively engaging tasks. There is, to the best of our knowledge, no published research examining the effects of concurrent cognitive tasks during walking on KAM. The aim of this study is to explore whether introducing cognitively engaging task during walking would affect the first peak of the KAM in healthy individuals.

Low back pain (LBP) is a major health problem that has now become leading cause of disability wor... more Low back pain (LBP) is a major health problem that has now become leading cause of disability worldwide. The majority of LBP has no specific pathological cause. Classification of non-specific LBP (NSLBP) into subgroups corresponding to the reported symptoms has been identified as an essential step towards the provision of personalised management and rehabilitation plans. Currently, clinicians classify low back pain patients into clinical subgroups based on clinical judgement and expertise, which is a time-consuming process open to human error. This paper introduces a novel approach for automatic classification of NSLBP patients into clinical subgroups on the basis of the MTw2 inertial measurement unit (MTw2 IMU tracker) motion data, which are portable units and thus desirable for clinical use. Four MTw2 IMU trackers tracking movement during a number of physical assessment tests were investigated in their ability to distinguish between clinically recognized NSLBP subgroups. Simple mo...

Journal of Clinical Medicine, 2020

Dual-task paradigms have been increasingly used to assess the interaction between cognitive deman... more Dual-task paradigms have been increasingly used to assess the interaction between cognitive demands and the control of balance and gait. The interaction between functional and cognitive demands can alter movement patterns and increase knee instability in individuals with knee conditions, such as knee anterior cruciate ligament (ACL) injury or osteoarthritis (OA). However, there is no consensus on the effects of dual-task on gait mechanics and balance in those individuals. This systematic scoping review aims to examine the impact of dual-task gait and standing balance on motor and cognitive performance in individuals with knee OA or ACL injury. A comprehensive search of MEDLINE, PubMed, Web of Science, and EMBASE electronic databases up until December 2019 was carried out. Inclusion criteria was limited to include dual-task studies that combined cognitive tasks performed simultaneously with gait or standing balance in individuals with knee OA or ACL injuries. In total, fifteen studie...

JMIR mHealth and uHealth, 2020

Background Movement analysis in a clinical setting is frequently restricted to observational meth... more Background Movement analysis in a clinical setting is frequently restricted to observational methods to inform clinical decision making, which has limited accuracy. Fixed-site, optical, expensive movement analysis laboratories provide gold standard kinematic measurements; however, they are rarely accessed for routine clinical use. Wearable inertial measurement units (IMUs) have been demonstrated as comparable, inexpensive, and portable movement analysis toolkits. MoJoXlab has therefore been developed to work with generic wearable IMUs. However, before using MoJoXlab in clinical practice, there is a need to establish its validity in participants with and without knee conditions across a range of tasks with varying complexity. Objective This paper aimed to present the validation of MoJoXlab software for using generic wearable IMUs for calculating hip, knee, and ankle joint angle measurements in the sagittal, frontal, and transverse planes for walking, squatting, and jumping in healthy...

Orthopedic Research and Reviews, 2019

Objective: To examine functional performance differences using kinematic and kinetic analysis bet... more Objective: To examine functional performance differences using kinematic and kinetic analysis between participants with and without knee osteoarthritis (OA) to determine which outcomes best characterize persons with and without knee OA. Methods: Participants with unilateral moderate knee OA (Kellgren-Lawrence grades 2 or 3) and controls without knee pain were matched for age, gender, and body mass index. Primary outcomes included temporal parameters, joint rotations and moments, and ground reaction forces assessed via 3D motion capture during walking and ascending/descending stairs. Secondary outcomes included timed functional activities (sit to stand; tying shoelaces), 48 hrs lower limb activity monitoring, and patient-reported outcome measures (Knee Injury and Osteoarthritis Outcome Score, Western Ontario and McMaster Universities Osteoarthritis Index, European Quality of Life-5 Dimensions). Results: Eight matched pairs were analyzed. Compared with controls, OA participants exhibited significant reductions in peak frontal hip and sagittal knee moments, and decreased peak anterior ground reaction force with the affected limb while walking. Ascending stairs, OA participants had slower speed, fewer strides per minute, longer cycle and stance times, and increased trunk range of motion (ROM) in assessments of both limbs; longer swing time and reduced ankle ROM in the affected limb; and increased knee frontal ROM in the unaffected limb. Descending stairs, OA participants had fewer strides per minute and decreased trunk transverse ROM in assessments of both limbs; increased knee frontal ROM in the affected limb; and longer strides, shorter stance and cycle times, increased trunk sagittal and decreased knee transverse ROMs in the unaffected limbs vs controls. Compared with controls, OA participants had slower walking cadence (120-130 vs 100-110 steps/min, respectively), took significantly longer on timed functional measures, and had significantly worse scores in patient-reported outcomes. Conclusion: Several objectives and patient-reported measures examined in this study could potentially be considered as outcomes in pharmacologic or physical therapy OA trials.

Journal of Rehabilitation and Assistive Technologies Engineering, 2019

Introduction Visual feedback is an effective method to enhance postural and balance control in cl... more Introduction Visual feedback is an effective method to enhance postural and balance control in clinical and sports training. The aim of this study was to explore the effect of real-time visual feedback provided by a video camera on the performance of a dynamic balance test, which is the star excursion balance test in healthy subjects. Methods We compared the performance of the star excursion balance test using the maximum reach distance in 20 healthy participants (10 male and 10 female, 26.8 ± 3.7 years) under two conditions: without feedback and whilst they viewed their movements in real-time on a screen in front of them via a video camera. Results The results showed that real-time visual feedback had a significant effect on maximum reach distance of the star excursion balance test in the posterolateral direction (P

Computer Methods in Biomechanics and Biomedical Engineering, 2017

Self-paced treadmill walking is becoming increasingly popular for the gait assessment and reeduca... more Self-paced treadmill walking is becoming increasingly popular for the gait assessment and reeducation, in both research and clinical settings. Its day-today repeatability is yet to be established. This study scrutinised the test-retest repeatability of key gait parameters, obtained from the Gait Real-time Analysis Interactive Lab (GRAIL) system. Twenty-three male able-bodied adults (age: 34.56 ± 5.12 years) completed two separate gait assessments on the GRAIL system, separated by 5 ± 3 days. Key gait kinematic, kinetic, and spatial-temporal parameters were analysed. The Intraclass-Correlation Coefficients (ICC), Standard Error Measurement (SEM), Minimum Detectable Change (MDC), and the 95% limits of agreements were calculated to evaluate the repeatability of these gait parameters. Day-today agreements were excellent (ICCs > 0.87) for spatial-temporal parameters with low MDC and SEM values, <0.153 and <0.055, respectively. The repeatability was higher for joint kinetic than kinematic parameters, as reflected in small values of SEM (<0.13 Nm/kg and <3.4°) and MDC (<0.335 Nm/kg and <9.44°). The obtained values of all parameters fell within the 95% limits of agreement. Our findings demonstrate the repeatability of the GRAIL system available in our laboratory. The SEM and MDC values can be used to assist researchers and clinicians to distinguish 'real' changes in gait performance over time.

Journal of Head Trauma Rehabilitation, 2018

Objective: The aim of this study was to evaluate current evidence for the effectiveness of virtua... more Objective: The aim of this study was to evaluate current evidence for the effectiveness of virtual reality (VR) interventions in improving neurocognitive performance in individuals who have sustained a traumatic brain injury (TBI). Methods: A systematic literature search was performed across multiple databases (PubMed, EMBASE, Web of Science) for articles of relevance. Studies were evaluated according to study design, patient cohort, VR intervention, neurocognitive parameters assessed, and outcome. VR interventions were evaluated qualitatively, with respect to methodology and extent of immersion, and quantitatively with respect to intervention duration. Outcomes: Our search yielded 324 articles, of which only 13 studies including 132 patients with TBI met inclusion criteria. A wide range of VR interventions and cognitive outcome measures were reported. Cognitive measures included learning and memory, attention, executive function, community skills, problem solving, route learning, and driving attitude. Several studies (n=10) reported statistically significant improvements in outcome, and two studies demonstrated successful translation into real-life performance. Conclusions: VR interventions hold significant potential for improving neuro-cognitive performance in patients with TBI. Whilst there is some evidence for translation into activities of daily living, further studies are required to confirm the validity of cognitive measures and reliable translation into real-life performance.

Sensors (Basel, Switzerland), Jan 28, 2018

The aim of this study was to investigate the reliability and concurrent validity of a commerciall... more The aim of this study was to investigate the reliability and concurrent validity of a commercially available Xsens MVN BIOMECH inertial-sensor-based motion capture system during clinically relevant functional activities. A clinician with no prior experience of motion capture technologies and an experienced clinical movement scientist each assessed 26 healthy participants within each of two sessions using a camera-based motion capture system and the MVN BIOMECH system. Participants performed overground walking, squatting, and jumping. Sessions were separated by 4 ± 3 days. Reliability was evaluated using intraclass correlation coefficient and standard error of measurement, and validity was evaluated using the coefficient of multiple correlation and the linear fit method. Day-to-day reliability was generally fair-to-excellent in all three planes for hip, knee, and ankle joint angles in all three tasks. Within-day (between-rater) reliability was fair-to-excellent in all three planes du...

2013 International Conference on Virtual Rehabilitation (ICVR), 2013

The study sought to explore the following: Analysis of Symmetry of the Support Moment between bot... more The study sought to explore the following: Analysis of Symmetry of the Support Moment between both legs. Collective feedback through responses to three closed-ended questions relating to safety, enjoyment, and ease of controlling the virtual object. Results and Discussion The preliminary results (see Table 1) indicate that controlling the virtual target can aid volunteers to equally distribute the support moment over both legs with least variation. Although the majority of the volunteers believed that their virtual stickfigure helped to squat with a better posture, the results demonstrate higher variation in symmetry of the support moment during this condition compared to the first and third condition. VR based on kinetic feedback is usually inaccessible to subjects in conventional approaches. This double leg squat exercise allowed them to succeed in using a biomechanically constrained strategy. The majority safely and easily controlled the virtual target with an adequate level of enjoyment.

Journal of Clinical Medicine, 2021

With the growing number of people affected by osteoarthritis, wearable technology may enable the ... more With the growing number of people affected by osteoarthritis, wearable technology may enable the provision of care outside a traditional clinical setting and thus transform how healthcare is delivered for this patient group. Here, we mapped the available empirical evidence on the utilization of wearable technology in a real-world setting in people with knee osteoarthritis. From an analysis of 68 studies, we found that the use of accelerometers for physical activity assessment is the most prevalent mode of use of wearable technology in this population. We identify low technical complexity and cost, ability to connect with a healthcare professional, and consistency in the analysis of the data as the most critical facilitators for the feasibility of using wearable technology in a real-world setting. To fully realize the clinical potential of wearable technology for people with knee osteoarthritis, this review highlights the need for more research employing wearables for information sha...

There is a need to consider a new framework for the development of virtual rehabilitation systems... more There is a need to consider a new framework for the development of virtual rehabilitation systems that are suitable for routine clinical use. With this in mind, a three-dimensional virtual reality (VR) system -the Surrey Virtual Reality System (SVRS) - that has been developed at the Centre for Biomedical Engineering , with the aim to be used as part of a rehabilitation programme for children with cerebral palsy (CP). Prior to the use of the SVRS with children with CP, opinions on the SVRS were gathered from 13 young adults aged between 19 and 25. The young adults were invited to review static 3D images and then to interact with two VR scenarios. They were then asked to walk on a treadmill at a number of self-selected and self-controlled walking speeds. During the tests, each participant answered a questionnaire that provided feedback on the SVRS and its practicality. The analysis of their opinions shows that the young adults were satisfied with the quality of the SVRS presentation. The results also show the feasibility of an algorithm for a self-controlled treadmill speed based on kinematic marker data with minimal encumbrance to the subject. All the users who used the SVRS were satisfied with the performance and the safety of the SVRS. In conclusion, the SVRS appears to provide a safe and visually acceptable virtual training environment.