Similar prevalence of acetabular labral tear in professional ballet dancers and sporting participants

OBJECTIVE: To compare the prevalence of acetabular labral tear in male and female professional ballet dancers with age-matched and sex-matched sporting participants and to determine the relationship to clinical findings and cartilage defects. DESIGN: Case-control study. SETTING: Clinical and radiology practices. PARTICIPANTS: Forty-nine (98 hips) male and female professional ballet dancers (current and retired) with median age 30 years (range: 19-64 years) and 49 (98 hips) age-matched and sex-matched sporting participants. INDEPENDENT VARIABLES: Group (ballet or sports), sex, age, hip cartilage defects, history of hip pain, Hip and Groin Outcome Score, passive hip internal rotation (IR), and external rotation range of movement (ROM). MAIN OUTCOME MEASURES: Labral tear identified with 3T magnetic resonance imaging (MRI). RESULTS: Labral tears were identified in 51% of all 196 hips. The prevalence did not differ significantly between the ballet and sporting participants (P = 0.41) or between sexes (P = 0.34). Labral tear was not significantly associated with clinical measures, such as pain and function scores or rotation ROM (P > 0.01 for all). Pain provocation test using IR at 90° of hip flexion had excellent specificity [96%, 95% confidence intervals (CIs), 0.77%-0.998%] but poor sensitivity (50%, 95% CI, 0.26%-0.74%) for identifying labral tear in participants reporting hip pain. Older age and cartilage defect presence were independently associated with an increased risk of labral tear (both P < 0.001). CONCLUSIONS: The prevalence of labral tear in male and female professional ballet dancers was similar to a sporting population. Labral tears were not associated with clinical findings but were related to cartilage defects, independent of aging. CLINICAL RELEVANCE: Caution is required when interpreting MRI findings as labral tear may not be the source of the ballet dancer's symptoms.

Minimising impairment: protocol for a multicentre randomised controlled trial of upper limb orthoses for children with cerebral palsy

BACKGROUND: Upper limb orthoses are frequently prescribed for children with cerebral palsy (CP) who have muscle overactivity predominantly due to spasticity, with little evidence of long-term effectiveness. Clinical consensus is that orthoses help to preserve range of movement: nevertheless, they can be complex to construct, expensive, uncomfortable and require commitment from parents and children to wear. This protocol paper describes a randomised controlled trial to evaluate whether long-term use of rigid wrist/hand orthoses (WHO) in children with CP, combined with usual multidisciplinary care, can prevent or reduce musculoskeletal impairments, including muscle stiffness/tone and loss of movement range, compared to usual multidisciplinary care alone.

METHODS/DESIGN: This pragmatic, multicentre, assessor-blinded randomised controlled trial with economic analysis will recruit 194 children with CP, aged 5-15 years, who present with flexor muscle stiffness of the wrist and/or fingers/thumb (Modified Ashworth Scale score ≥1). Children, recruited from treatment centres in Victoria, New South Wales and Western Australia, will be randomised to groups (1:1 allocation) using concealed procedures. All children will receive care typically provided by their treating organisation. The treatment group will receive a custom-made serially adjustable rigid WHO, prescribed for 6 h nightly (or daily) to wear for 3 years. An application developed for mobile devices will monitor WHO wearing time and adverse events. The control group will not receive a WHO, and will cease wearing one if previously prescribed. Outcomes will be measured 6 monthly over a period of 3 years. The primary outcome is passive range of wrist extension, measured with fingers extended using a goniometer at 3 years. Secondary outcomes include muscle stiffness, spasticity, pain, grip strength and hand deformity. Activity, participation, quality of life, cost and cost-effectiveness will also be assessed.

DISCUSSION: This study will provide evidence to inform clinicians, services, funding agencies and parents/carers of children with CP whether the provision of a rigid WHO to reduce upper limb impairment, in combination with usual multidisciplinary care, is worth the effort and costs.

The centrality of the Australian suburb: mobility challenges and responses by outer suburban residents of Melbourne

Living in the suburbs is founded on mobility, as residents move to the periphery of the city, commute to work and travel for shops, schools and leisure. While there have been numerous studies raising critical questions on the vulnerability of outer suburban residents to loneliness, financial and mortgage stress, the actual experiences and challenges posed by the dependence of suburban life on mobility is rarely singled out for attention. Through purposive sampling and then snowballing, eight outer suburban residents participated in photo-elicited interviewing to detail their lifeworlds and mobility experiences. Problems ranged from getting to work to accessing schools, shops and even neighbourhood services as the suburban car culture was embraced but also constrained patterns of movement. However, there was also an array of positive experiences and alternatives to these patterns, including the pleasures to be found in traffic jams and the suburban environment and local actions to establish new pathways and means of movement as well as set up local employment options. Mobility constraint thereby generated a range of unexpected strategies, as residents exercised their agency to shape their experiences, create alternatives and to build suburban centred lives.

Key questions in marine megafauna movement ecology

It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology.

Look down, look up : Barbara Bolt's art beyond representation

I review the thinking of Barbara Bolt in her recent book, which is informed by Martin Heidegger’s theory of art. Bolt argues that it is in the flux of art practice, where the artist responds bodily, with hands and eyes, to the encounter with the materials of practice, that visual art produces real material effects. That is, through the praxical encounter, art does not merely represent, it performs radically. Bolt thus argues for a materialist ontology of the work of visual art. I examine what Bolt means by ‘real material effects’ and ‘radical performativity’.

In developing my own project on the poetic response to visual art, particularly portraiture, I have freely adapted Heidegger’s theory of art to propose that the poet responds to the visual encounter in a manner similar to that of Heidegger’s preserver, by restraining usual knowing and looking. In this way the poet facilitates the emergence from the work of visual art of truth about being and earth, as defined by Heidegger. In my forthcoming article ‘Ekphrasis and illumination of painting’, I argue that the poet, like the artist, restrains seeing-as and operates in a mode approximating mere seeing, as these terms are defined by Heidegger and Wittgenstein.

In the present article I propose to examine the role of looking down and looking up in non-representational art, and in particular Bolt’s ‘oil stain paintings’ exhibited in the Forty-five Downstairs gallery in Melbourne in conjunction with the launch of her book.

I propose to expose some blind spots in the thinking which underpins theories derived from Heidegger. I will examine the way ‘representation’ has been constructed in twentieth-century thought, and will argue that Heideggerian truth and Bolt’s ‘real material effects’ result from the privileging of perception over knowledge. I will examine, with particular reference to portraiture, Bolt’s assertion that the referent can be rehabilitated in Western thought and traced in ‘real material effects’. I will argue that ‘representation’ is an unstable process occurring within and outside signification, and that this very instability enables us to confidently predict that all art produces ‘real material effects’, or in other words, Heideggerian truth.

Learning to minimize energy costs and maximize mechanical work in a bimanual coordination task

The authors addressed the hypothesis that economy in motor coordination is a learning phenomenon realized by both reduced energy cost for a given workload and more external work at the same prepractice metabolic and attentional energy expenditure. "Self-optimization" of movement parameters has been proposed to reflect learned motor adaptations that minimize energy costs. Twelve men aged 22.3 [+ or -] 3.9 years practiced a 90[degrees] relative phase, upper limb, independent ergometer cycling task at 60 rpm, followed by a transfer test of unpracticed (45 and 75 rpm) and self-paced cadences. Performance in all conditions was initially unstable, inaccurate, and relatively high in both metabolic and attentional energy costs. With practice, coordinative stability increased, more work was performed for the same metabolic and attentional costs, and the same work was done at a reduced energy cost. Self-paced cycling was initially below the metabolically optimal, but following practice at 60 rpm was closer to optimal cadence. Given the many behavioral options of the motor system in meeting a variety of everyday movement task goals, optimal metabolic and attentional energy criteria may provide a solution to the problem of selecting the most adaptive coordination and control parameters.

What drives long-distance movements in the nomadic Grey Teal Anas gracilis in Australia?

In contrast to northern temperate environments, where day length and temperature changes are obvious proximate cues for movement to resource-rich breeding habitats, the cues for movement used by birds in an often resource-poor, stochastic environment are less obvious. We recorded long-distance movements of 23 Grey Teal Anas gracilis using satellite telemetry for up to 879 days and examined the relationship between those movements and environmental factors, such as heavy rainfall and flooding, at the destination site. We identified 32 long-distance [> 150 km) movements that met our criterion for minimally interrupted flight between origin and destination. Thirteen of these flights coincided with rainfall and/or flooding events up to 1050 km from the origin. However, some ducks moved without any clear beneficial conditions at the destination onto small wetlands in regions with little surface water. The data suggest that there are two types of long-distance movement - ranging and directed. These flights occurred over distances up to 1200 km across the arid inland. The rates and distances of movement suggest that long-distance movements of Grey Teal entail high energy costs as in waterfowl elsewhere. We conclude that the proximate controls of directIn contrast to northern temperate environments, where day length and temperature changes are obvious proximate cues for movement to resource-rich breeding habitats, the cues for movement used by birds in an often resource-poor, stochastic environment are less obvious. We recorded long-distance movements of 23 Grey Teal Anas gracilis using satellite telemetry for up to 879 days and examined the relationship between those movements and environmental factors, such as heavy rainfall and flooding, at the destination site. We identified 32 long-distance (> 150 km) movements that met our criterion for minimally interrupted flight between origin and destination. Thirteen of these flights coincided with rainfall and/or flooding events up to 1050 km from the origin. However, some ducks moved without any clear beneficial conditions at the destination onto small wetlands in regions with little surface water. The data suggest that there are two types of long-distance movement – ranging and directed. These flights occurred over distances up to 1200 km across the arid inland. The rates and distances of movement suggest that long-distance movements of Grey Teal entail high energy costs as in waterfowl elsewhere. We conclude that the proximate controls of directed movements need not be very different from those of their temperate counterparts.ed movements need not be very different from those of their temperate counterparts.

On animal distributions in dynamic landscapes

Few landscapes are static and patterns of resource distribution can vary markedly in time and space. Patterns of movement and dispersal in response to environmental change are equally diverse and occur on a broad range of temporal scales. For patterns of movement and dispersal that vary spatially and temporally throughout the life-time of an individual, the concepts of home range and geographic range alone do not adequately describe the observed patterns of distribution of individuals, populations or species. Here we further simplify Gauthreaux (1982) classification of movement types into a simple bipartite system and link movements (or lack thereof) to a similarly simple classification of ranges. In addition, we introduce two new indices that describe the relationship of an individual's life-time movements to its distribution as described by home and geographic range. Our interest in this subject arose from endeavouring to interpret local changes in waterbird abundance in the arid interior of the Australian continent and to understand these changes in relation to patterns of resource distribution and movement. In this discussion we focus on terrestrial vertebrates capable of multiple breeding events throughout an extended life-time.

Polyhedral : recycling boundary ecologies

Foregrounding the extent to which 'place' remains resistant to the politics and poetics of 'network culture', this essay approaches place as a boundary ecology rather than as an instance of cultural invariance. It calls on readers to think about attempts to actively recycle cultural 'debris' or 'waste' through an ethics of passage instead of the kind of instrumentalist statics that prevents the development of an ontology of mobility. Con-tending that such a capacity to inhabit passage is compromised by the eschatological language used to communicate the implications of environmental disaster, as well as by languages of consultation that (con-ceptually) empty place of any creative power to incubate alternatives – events, modes of relation –, the essay stresses the mythopoetic techniques that produce places as knots or nodal points within a network of pas-sage. The designer's task is to create the hinge mechanisms that render such boundary ecologies inhabitable imaginatively, and by materialising the nexus between creativity and change to alter our position vis-a-vis our ethical responsibilities as citizens of a shared biosphere.

Invertebrate larval dynamics in seasonally closed estuaries

Estuarine benthic assemblages are often numerically dominated by polychaetes. The limits of these populations are determined by larval, and probably to a lesser extent adult movement. A previous study (Newton 1996), indicated that planktonic polychaete larvae were very abundant over the summer months in the Hopkins River; however, the identification and source of these larvae was not known. Defining the extent of a population, and therefore the likelihood of that population recovering following a perturbation, is crucial for effective estuarine management. This study investigated both the likely source of the larvae, (i.e. estuarine or marine) and the extent of larval dispersal within and between estuaries by addressing the following questions: Which taxa produced the planktonic larvae? Are these taxa resident estuarine species? Are the larvae of different taxa evenly distributed within the estuary or do physicochemical parameters or other factors influence their abundance? Are the same larvae found in other estuaries along the coast? and Is there exchange of these larval taxa with the marine environment and other estuaries? Larvae were identified and described by culturing commonly occurring planktonic larvae until adult characteristics appeared. The spionids, Carazziella victoriensis and Prionospio Tatura, numerically dominated the plankton in the Hopkins and the spionid, Orthoprionospio cirriformia was recorded from the Hopkins, Curdies and Gellibrand estuaries. Two spionids, Carazziella sp. and Polydora sp. were identified from tidal waters. Mouth status and physicochemical conditions (salinity, temperature and dissolved oxygen) were monitored in each estuary. Whereas the Merri and Gellibrand estuaries were predominantly stratified over the sampling period, the Curdies was more often well mixed and the Hopkins varied from well mixed to stratified. The duration of mouth opening and hence the opportunity for larval exchange also varied in each estuary. The Merri River was closed for 13.5% of days over the study period, the Gellibrand River for 18.4%, the Hopkins River for 49% and the Curdies River for 71.0%. The distributions of larvae at spatial scales of metres, 100s of metres and kilometres were investigated within a single estuary. While the same larvae, C. victoriensis, P. Tatura and bivalve larvae, were found along the length of the Hopkins estuary the abundances varied at different spatial scales suggesting different processes were influencing the distribution of P. Tatura larvae, and C. victoriensis and bivalve larvae. The distribution of larvae between several estuaries was investigated by monitoring meroplankton at two sites at the mouth of each of the four estuaries approximately monthly (except for winter months). Different meroplanktonic assemblages were found to distinguish each estuary. Further, C. victoriensis and P. Tatura larvae were only recorded in the Hopkins but larvae of the spionid, Orthoprionopio cirriformia were detected in the Hopkins, Curdies and Gellibrand estuaries. The extent of larval exchange with other estuaries and the marine environment was determined by monitoring tidal waters. Settlement trays were also deployed to determine if larvae were moving into estuaries and settling but not recruiting. P. tatura larvae were not detected in the tidal waters of any estuary and while C. victoriensis and O. cirriformia were found in both flood and ebb tides there was no evidence of movement of theses taxa to other estuaries. Larvae of the spionids, Carazziella sp. and Polydora sp., were found in tidal waters of each estuary but were rarely detected in the plankton within the estuaries. Neither species was found as an adult in background cores from any estuary, nor with the exception of a few individuals in the Merri, were they detected in settlement trays in any estuary. I conclude that the source of the larvae of C. victoriensis, P. Tatura and O. cirriformia is estuarine and while C. victoriensis, and O. cirriformia move in and outh of the source estuary in tidal waters there was no evidence for movement to other estuaries. The spionids, Carazziella sp. and Polydora sp were considered to be marine and while they moved in and out of estuaries in tidal waters they did not usually settle in the estuaries. The results of this study are a crucial first step in the development of ecological models to better understand dispersal in seasonally closed estuaries that are typical of southern Australia. This study emphasises the unique physicochemical characteristics and biological assemblages within these estuaries and the need for estuarine management to reflect these differences.

Capturing dance and choroetopography : analyzing and visualizing complexity

 Motion capture provides 'snapshots' of the complexity of movement patterning.  This presentation explores how this complexity can be mapped to specific variables for analysis, and what such analyses both reveal and mask in relation to the choreographic practices involved, drawing on my three-year collaboration with mathematician Vicky Mak-Hau and biomechanist Richard Smith at the Deakin Motion.Lab in Melbourne, Australia.  The paper explores how these analyses can potentially drive creative processes in dance, and, through a discussion of performance project Choreotopography, how real-time motion capture can visualize and enhance spatial pathways using 3D stereoscopic projection.

Tuning fork: Shopfront

The audience of this performance got to view actions and installations building and evolving over time, and a projected time-lapse video.
In this iteration of Tuning Fork, James Cunningham & Joncli Keane continue the development of their two pronged approach to finding the watering hole of stillness and action, collabora tion and orientation.Originating from a showing in the Bell Tower II series, in the Judy's new Shopfrontspaoe, Tuning Fork will Fuks accentuate the durational aspect of movement through time-lapse video, heighten the trans formative potential of objects using three-metre long carbon rods as instruments of sense, sound and support and alter the space through the numerous tape measures which take on a life of their own. James Cunningham and Jondi Keane inhabit the Shopfront from Friday 7 November, eJqJioring, measuring, filming and projecting, in order to fine tune their interactions for the performance season commencing 19 November.

Detecting deviations from known paths and speeds in a surveillance situation

This paper presents techniques for analysing human behaviour via video surveillance. In known scenes under surveillance, common paths of movement between entry and exit points are obtained and classified. These are used, together with a priori velocity data, to serve as a model of normal traffic flow in the scene. Surveillance sequences are then processed to extract and track the movement of people in the scene, which is compared with the models to enable detection of abnormal movement

The performing frame

This project explores the ways that creative practices—improvised movement, choreographed dance, and digital video—produce new knowledge about the sociability of public space. In other words, it uses various theoretical concepts and practical strategies to document and analyse the ways people inhabit and sometimes subvert public spaces — such as plazas, malls and piazzas — as part of their everyday experience. Drawing on concepts developed within the fields of performance theory, spatial history, cultural geography and social theory, the project will build a methodological toolbox for understanding the relationships between the diverse groups that use public spaces in Melbourne, Australia. This ‘toolbox’ will subsequently be used to understand analogous public spaces in other parts of the world to generate comparative data about spatial sociability. The research will enable an innovative way of mapping social, civic and political relations in space through a series of creative interventions, and will reveal the politics of everyday movement while exposing tensions between the spaces of public culture — those framed and legitimated by state institutions — and what Michael Warner calls ‘Counter-Publics.’ That is, those oppositional groups who actively seek to use public space in subversive or unauthorised ways.

This project documents a series of performative interventions designed to harness the untapped potential of various forms of street performance genres to function as tools that can produce new ways of understanding the politics of movement in public space. These ‘interventions’ will be generated through a series of practical performance and movement workshops that will draw on street theatre techniques, contact improvisation, Laban movement analysis and contemporary dance choreography. The project will focus on a series of dyadic relationships: self and other, inside and outside, centre and periphery that are relevant to human interaction in public space.
Street performers — musicians, acrobats, jugglers, magicians, mimes and so on — seek public spaces with high volumes of pedestrian traffic in order to maximise their ability to draw an audience and make a living. These performers who create temporary performance zones alter the flow and intensity of movement around them, thereby transforming the plazas, piazzas, town squares and subways favoured by buskers. Some of these performers interact with their audience more than others, and are potentially capable of telling us something about the politics of space. The practice of ‘shadowing’ the movements of passers-by is an increasingly popular form of public entertainment around the world.

Orbiting data: inciting centrifugal questions about embodied learning in science

In this paper we explore how reanimating a video data sequence with editing and creative software provided an opportunity for the data to speak and to demand new and surprising responses from us. Our data-ing brought new lines and spaces to the fore, through a process of refraction and re-animation which forced a focus on embodied inter-relationships and impeded precipitous analytical thought on the part of the researcher. We note how the aesthetic of the new images evoked awareness of our own part in the production of the object of our research. In particular, our own collegial interchange, punctuated by time and distance due to our respective locations on opposite sides of the globe, opened up a space for data-lingering in the intervening silences and pauses. Our choice of images engenders and reflects our sense of movement between the `I’ and the `we’ in their depiction of students’ learning about space.