Avoidance behaviours while circumventing to the left or right of someone with different shoulder widths and facing directions: How do side, width, or orientation matter?

BACKGROUND: Collision avoidance during locomotion is influenced by a variety of situational factors. When circumventing around an inanimate object, the amount of clearance is dependent on the side of avoidance. When avoiding other pedestrians, individuals most often choose to walk behind a moving pedestrian, and avoid people differently depending on their body size. However, side of avoidance has not been evaluated with human obstacles, nor facing direction of a stationary pedestrian, nor the size of a single pedestrian. Therefore, the aim of this study is to evaluate these knowledge gaps concurrently. RESEARCH QUESTION: How do people avoid a collision to the left-side or right-side of a single stationary pedestrian (interferer) of varying shoulder width and orientation? METHODS: Participants (n = 11) walked along a 10 m pathway towards a goal, while a stationary interferer stood 6.5 m from the start. The interferer faced one of three directions relative to the participant (orientation); forward, leftward, or rightward, with either their normal shoulder width or enlarged width created by wearing football shoulder pads. Participants were explicitly instructed as to which side of the interferer to avoid (forced-left vs forced-right). Each participant completed 32 randomized avoidance trials. Centre of Mass separation at the time of crossing was used to examine individual's avoidance behaviours. RESULTS: Results revealed no effect of interferer width, but a significant side of avoidance effect, where the centre of mass separation between the participant and interferer at the time of crossing was smallest when participants avoided to their left. SIGNIFICANCE: Findings suggest that changing the facing direction or artificially increasing the shoulder width of a stationary interferer will not affect one's avoidance behaviours. However, an asymmetry in side of avoidance is maintained similar to that observed in obstacle avoidance behaviours.

Collision avoidance behaviours between older adult and young adult walkers.

BACKGROUND: Collision avoidance between two walkers requires a mutual adaptation based on visual information in order to be successful. Age-related changes to visuomotor processing, kinesthetic input, and intersegmental dynamics increases the risk of collision and falls in older adults. However, few studies examine behavioural strategies in older adults during collision avoidance tasks with another pedestrian. RESEARCH QUESTION: Is there a difference between older adults' and young adults' collision avoidance behaviours with another pedestrian? METHODS: Seventeen older adults (x¯ = 68 ± 3 years) and seventeen young adults (x¯ = 23 ± 2 years) walked at a comfortable walking speed along a 12.6 m pathway while avoiding another walker. Trials were randomized equally to include 20 interactions with the same age group and 21 interactions with the opposite age group. Minimum predicted distance (mpd) was used to characterize collision avoidance behaviours between older adults and young adults. RESULTS: Older adults had riskier avoidance behaviours, passing closer to the other pedestrian (0.79 m ± 0.18 m) compared to when two young adults were on a collision course (0.93 m ± 0.17 m) (χ²(3) = 35.94, p < .0001). Whenever an older adult was on a collision course with a young adult, the young adult contributed more to the avoidance regardless of passing order. SIGNIFICANCE: The results from the current study highlight age-related effects during a collision avoidance task in older adults resulting in risky behaviour and a potential collision. Future studies should further investigate age-related visuomotor deficits during collision avoidance tasks in cluttered environments using virtual reality in order to tease out factors that contribute most to avoidance behaviours in older adults.

Collision avoidance behaviours when circumventing people of different sizes in various positions and locations.

The current study examined whether young adults' avoidance behaviours differed when circumventing a larger versus smaller interferer. It was expected that avoidance behaviours (repulsion) would be affected by the interferer's size (i.e., greater repulsion for larger body size). Participants (n = 20) walked along an 8 m pathway towards a goal while avoiding either a larger or smaller sized male interferer who stood stationary facing forward, backward, left, or right and were located 2, 4, or 6 m from the participants' starting position. Results revealed that there was an effect of interferer body size (personal-characteristics) and orientation (situational-characteristics) on M-L clearance between the interferer and participant at the time of crossing, suggesting that repulsion magnitudes are scaled to an interferer's closest body surface.

Fibromyalgia and myofascial pain syndrome: Two sides of the same coin? A scoping review to determine the lexicon of the current diagnostic criteria.

OBJECTIVE: Consistent terminology to describe the diagnostic criteria for fibromyalgia (FM) and myofascial pain syndrome (MPS) is required to address the reported inadequacies in diagnosis. The present review investigated intervention studies in FM and MPS populations to determine the lexicon of the current diagnostic criteria used to identify chronic musculoskeletal pain patients. METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a scoping review to review systematically the literature obtained from five scientific databases between 1997 and February 2017. Included studies consisted of intervention studies that involved symptomatic musculoskeletal pain patients, of any age or gender, presenting with FM or MPS. Included studies were evaluated for musculoskeletal condition and the diagnostic criteria used to identify patient conditions. Extraction of study criteria focused on whether diagnostic criteria were explicitly stated, the diagnostic criteria used, physical findings, symptomatic duration and the profession of the healthcare provider who confirmed diagnosis. RESULTS: We identified 493 interventions, of which 410 were related to FM and 83 to MPS. The lexicon of the diagnostic criteria used for MPS tended to be less consistent in comparison to FM criteria, with notable differences in all comparative categories. CONCLUSIONS: The current review identified inconsistencies associated with the lexicon of the diagnostic criteria used to diagnose FM and MPS, and showed that there is wide variability in the terminology currently being used. These findings may have important implications for future development of consistent criteria to diagnose FM and MPS patients accurately.

A comparison of the clinical manifestation and pathophysiology of myofascial pain syndrome and fibromyalgia: implications for differential diagnosis and management.

Two prominent forms of chronic musculoskeletal pain disorders are fibromyalgia (FM) and myofascial pain syndrome (MPS). Inconsistent diagnosis of chronic musculoskeletal pain is an important clinical issue, as MPS is often mistaken for FM. Distinction between the two diagnoses depends largely on identification of either tender points or myofascial trigger points in FM and MPS, respectively. However, there currently is no standard diagnostic protocol for MPS. Consequently, this results in a lack of consistency across health care practitioners diagnosing both FM and MPS. Therefore, developing sensitive and reliable mechanism-based diagnostic criteria is imperative to the field of musculoskeletal pain. The focus of this review is to discuss the common and unique features of FM and MPS in the context of their epidemiology, clinical features, and pathophysiology. This review will address inconsistency among health care practitioners' diagnoses, and present alternative diagnostic tools with potential for inclusion into a mechanism-based diagnostic protocol.

La fibromyalgie (FM) et le syndrome de douleur myofasciale (SDM) sont deux formes de douleur musculosquelettique chronique. Le SDM est souvent confondu avec la FM; un manque de cohérence dans l'établissement d'un diagnostic de douleur musculosquelettique constitue un problème clinique grave. La différence entre les deux diagnostics dépend en grande partie de l'identification des points sensibles ou des points déclencheurs de FM et du SDM, respectivement. Mais il n'existe toujours pas de protocole normalisé pour diagnostiquer le SDM, ce qui explique le manque de cohérence observé chez les professionnels de la santé qui posent des diagnostics de FM ou de SDM. Il est donc primordial d'établir des critères diagnostiques fondés sur un mécanisme cohérent et fiable pour ce qui est de la douleur musculosquelettique. La présente revue vise à examiner les caractéristiques communes et particulières de la FM et du SDM en tenant compte de leur épidémiologie, leurs caractéristiques cliniques et leur physiopathologie. Dans la présente revue, nous abordons l'incohérence des diagnostics posés par des professionnels de la santé et présentons d'autres outils diagnostiques permettant l'inclusion d'un protocole fondé sur un mécanisme.