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Although breast pain has been related to vertical breast displacement and velocity, the influence of breast support on multi-planar breast kinematics and breast comfort has yet to be ascertained. The aims of this study were to investigate multi-planar breast displacement, velocity, and acceleration with and without breast support during running and to establish the correlation with breast comfort. Fifteen females ran at 2.8 m · s-1 in no bra, an everyday bra, and a sports bra. Three-dimensional coordinates of breast and body markers were tracked during ten gait cycles and following each trial the participants rated their breast comfort. Relative breast displacement was calculated and derived for velocity and acceleration. Vertical breast displacement, velocity, and acceleration peaked at, before, and after mid-stance, respectively. The patterns of displacement and velocity trajectories were unaffected by increasing breast support, though the magnitudes were significantly reduced. The magnitude and trajectory of breast acceleration was unaffected by increasing breast support and showed no correlation with comfort. Breast velocity displayed the strongest relationship to comfort (r = 0.61). Considerable mediolateral and anteroposterior breast kinematics were identified, suggesting that future studies and bra design may benefit from three-dimensional analysis. In conclusion, improvements in breast support may be defined by reductions in breast velocity and displacement. [ABSTRACT FROM AUTHOR]

Background: Advances in the management of Achilles tendon rupture have led to the development of immediate weightbearing protocols. These vary regarding which ankle-foot orthoses (AFOs) are used and the number of inserted heel wedges used within them.Purpose: This study was conducted to evaluate plantar pressure measurements and temporal gait parameters within different AFOs, using different numbers of heel wedges.Study Design: Controlled laboratory study.Methods: Fifteen healthy participants were evaluated using 3 different AFOs, with 4 different levels of inserted heel wedges. Therefore, a total of 12 conditions were evaluated, in a sequence that was randomly allocated to each participant. Pressure and temporal gait parameters were measured using an in-shoe F-Scan pressure system, and range of movement was measured using an electrogoniometer.Results: Ankle-foot orthoses that were restrictive in design, combined with a higher number of inserted heel wedges, reduced forefoot pressures, increased heel pressures, and decreased the amount of time spent in the terminal stance and preswing phase of the gait cycle (P = .029, .002, and .001).Conclusion: The choice of AFO design and the number of inserted heel wedges have a significant effect on plantar pressure measurements and temporal gait parameters. The implications of these changes need to be applied to the clinical management of acute Achilles tendon ruptures. This clinical management requires a balance between protected weightbearing and functional loading, requiring further research within a clinical context.Clinical Relevance: The biomechanical data from this research imply that a carbon-fiber AFO, with 1 heel raise, protects against excessive dorsiflexion while facilitating the restoration of near-normal gait parameters. This could lead to an accelerated return to function, avoiding the effects of disuse atrophy. This is in contrast to the rigid rocker-bottom AFO design with a greater number of heel-wedge inserts. However, research within a clinical context would be required to ascertain if these biomechanical advantages translate into a functional benefit for patients. The results should also be considered in relation to the amount of force a healing Achilles tendon can withstand. [ABSTRACT FROM AUTHOR]

Objectives To determine whether digital gait biomarkers captured by a wrist-worn device can predict injurious falls in older people and to develop a multivariable injurious fall prediction model. Design Population-based longitudinal cohort study. Setting and participants Community-dwelling participants of the UK Biobank study aged 65 and older (n  = 32,619) in the United Kingdom. Methods Participants were assessed at baseline on daily-life walking speed, quality, quantity and distribution using wrist-worn accelerometers for up to 7 days. Univariable and multivariable Cox proportional hazard regression models were used to analyse the associations between these parameters and injurious falls for up to 9 years. Results Five percent of the participants (n  = 1,627) experienced at least one fall requiring medical attention over a mean of 7.0 ± 1.1 years. Daily-life walking speed, gait quality, quantity of walking and distribution of daily walking were all significantly associated with the incidence of injurious falls (P  < 0.05). After adjusting for sociodemographics, lifestyle factors, comorbidities, handgrip strength and reaction time; running duration, total step counts and usual walking speed were identified as independent and significant predictors of falls (P  < 0.01). These associations were consistent in those without a history of previous fall injuries. In contrast, step regularity was the only risk factor for those with a previous fall history after adjusting for covariates. Conclusions Daily-life gait speed, quantity and quality, derived from wrist-worn sensors, are significant predictors of injurious falls in older people. These digital gait biomarkers could potentially be used to identify fall risk in screening programs and integrated into fall prevention strategies. [ABSTRACT FROM AUTHOR]

Appropriate breast support is recommended in sport; however, what constitutes appropriate support is complex, individual and often sports specific, particularly in elite sport given the wear duration. This intervention educated, assessed and advised elite British female athletes on breasts and bras; those with unresolved issues engaged in bespoke bra interventions. Following educational workshops (n = 80), breast/bra surveys (n = 60), individual bra assessments (n = 37); a rower, shooter, and hockey player participated in the bespoke bra intervention. Eighty-three per cent of athletes rated their breast/bra knowledge as ≤average. Fifty-one per cent experienced breast pain, affecting performance for 29%; seven used medication and one surgery to relieve symptoms. In individual bra assessments most wore ill-fitting, unsupportive bras and wanted bra advice. Bespoke bra interventions eliminated breast pain: for the rower, improved breast position and spine rotation; for the shooter, repositioned tissue and improved performance; and for the hockey player, accommodated smart devices. Whilst bespoke bra development is challenging, most elite athlete breast/bra issues are resolved via education, advice and fitting. [ABSTRACT FROM AUTHOR]

Due to basal ganglia dysfunction, short step length is a common gait impairment in Parkinson's disease (PD), especially in a dual-task walking. Here, we use electroencephalography (EEG) functional connectivity to investigate neural mechanisms of a stride awareness strategy that could improve dual-task walking in PD. Eighteen individuals with PD who had mild gait impairment walked at self-paced speed while keeping two interlocking rings from touching each other. During the dual-task walking trial, the participants received or did not receive awareness instruction to take big steps. Gait parameters, ring-touching time, and EEG connectivity in the alpha and beta bands were analyzed. With stride awareness, individuals with PD exhibited greater gait velocity and step length, along with a significantly lower mean EEG connectivity strength in the beta band. The awareness-related changes in the EEG connectivity strength of the beta band positively correlated with the awareness-related changes in gait velocity, cadence, and step length, but negatively correlated with the awareness-related change in step-length variability. The smaller reduction in beta connectivity strength was associated with greater improvement in locomotion control with stride awareness. This study is the first to reveal that a stride awareness strategy modulates the beta band oscillatory network and is related to walking efficacy in individuals with PD in a dual-task condition. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare postural sway during a series of static balancing tasks and during five chair rises between healthy young (mean [SEM], age 26 [1] years), healthy old (age 67 [1] years) and master athlete runners (age 67 [1] years; competing and training for the previous 51 [5] years) using the Microsoft Kinect One. The healthy old had more sway than the healthy young in all balance tasks. The master athletes had similar sway to young athletes during two-leg balancing and one-leg standing with eyes open. When balancing on one leg with eyes closed, both the healthy old and the master athletes had around 17-fold more sway than the young athletes. The healthy old and master athletes also had less anterio-posterior movement during chair rising compared with young athletes. These results suggest that masters runners are not spared from the age-associated decline in postural stability and may benefit from specific balance training. [ABSTRACT FROM AUTHOR]

CONTEXT: Hamstring injury-risk assessment has primarily been investigated using isokinetic dynamometry. However, practical issues such as cost and availability limit the widespread application of isokinetics for injury-risk assessment; thus, field-based alternatives for assessing eccentric hamstring strength are needed. OBJECTIVE: The aim of this study was to investigate the validity of the angle achieved during Nordic hamstring lowers (break-point angle) as a field-based test for eccentric hamstring strength. DESIGN: Exploratory study. SETTING: Laboratory. PARTICIPANTS: Sixteen male (n = 7) and female (n = 9) soccer players (mean ± SD age 24 ± 6 y, height 1.77 ± 0.12 m, and body mass 68.5 ± 16.5 kg) acted as subjects for the study. MAIN OUTCOME MEASURES: The authors explored relationships between the Nordic break-point angle (the point at which the subject can no longer resist the increasing gravitational moment during a Nordic hamstring lower) measured from video and isokinetic peak torque and angle of peak torque of right- and left-knee flexors. RESULTS: The results revealed a meaningful relationship between eccentric knee-flexor peak torque (average of right and left limbs) and the Nordic break-point angle (r = -.808, r2 = 65%, P < .00001). However, there was a weak relationship observed (r = .480, r2 = 23%, P = .06) between break-point angle and the angle of peak torque (average of right and left limbs). CONCLUSIONS: The results suggest that the break-point angle achieved during Nordic hamstring lowers could be used as a field-based assessment of eccentric hamstring strength. [ABSTRACT FROM AUTHOR]

Purpose: Previous research suggests that many active females are not engaging in sports bra use, despite the positive health benefits. The aim of this study was to establish and compare sports bra use, preferences and bra fit issues for exercising females in some of the largest and most diverse global underwear markets (the US, the UK and China). Design/methodology/approach: A survey covering activity levels, sports bra use and preferences, bra issues and demographics was administered via Qualtrics and completed by 3,147 physically active females (aged ≥ 18 years) from the US (n = 1,060), UK (n = 1,050) and China (n = 1,037). Findings: In general, participants were 25–29 years, 121 to 140 pounds, 34B bra size and pre-menopausal. "I cannot find the right sports bra" was the most frequent breast barrier to exercise (25.4%). Three-quarters of women wore a sports bra during exercise, with significantly higher use in China (83.9%), compared to the UK (67.2%). A third of all participants reported sports bra shoulder straps "digging into the skin". Sports bra preferences were: compression sports bras with a racer back, wide straps and thick straps in the US and the UK; thin straps in China and adjustable straps and underband, no wire and maximum breast coverage in the US and the UK, including nipple concealment and with padded/moulded cups. Originality/value: Information provided on differences in sports bra use, preferences and bra issues across three major global markets could be utilised by brands and manufacturers to optimise bra marketing and fit education initiatives and inform future sports bra design and distribution strategies. [ABSTRACT FROM AUTHOR]

Purpose: A potential method to relieve the pain from medial osteoarthritis of the knee is to offload the medial compartment. The Latella™ Knee Implant is a novel device designed to offload the medial compartment. The objective of the Cotera-1 study was to evaluate the preliminary safety and feasibility of the Latella implant to treat patients with medial OA of the knee, by a 2-year follow-up of a prospective multicenter feasibility study (Cotera-1) performed in the Netherlands and UK Methods: In this first-in-man study, 11 participants received the Latella implant and were followed for 2 years, documenting physician assessment, Patient-Reported Outcome (PRO) scoring (KOOS, IKDC, Kujala, SF-36); Patient Global Assessment (PGA), radiographic analysis and MRI analysis, complications, reoperation rate and hip–knee–ankle axis. Results: The Latella Knee Implant system proved to be well tolerated and demonstrated a low-risk safety profile up to 24 months post-treatment. A responder analysis was performed of the subjects who still had the Latella implanted at 24-month time point (n = 9). Based on a MCID of eight for KOOS pain sub-scale, 78% of the subjects at the 24 month time point would be considered as responders. Similarly, based on improvement in the medial knee pain compared to baseline using the NRS scale of 1–10, 89% of the subjects at the 24-month time point would be considered as responders. Two patients were revised during follow-up: one for arthrofibrosis and one converted to TKA for progression of OA. Conclusions: The early clinical experience with the Latella Knee Implant in this pilot feasibility study has been encouraging. It appears to be a safe implant with possible effect on medial OA. Additional studies need to be performed to assess the safety and efficacy of the procedure in a larger patient population. Level of evidence: II [ABSTRACT FROM AUTHOR]

Drop-Foot is a common problem resulting from a range of neurological conditions, and prevents normal leg swing during gait, leading to abnormal, inefficient motion with an increased risk of falling. It damages the quality of life of over 122,000 people in the US and 11,400 people in the UK every year. Functional electrical stimulation (FES) addresses drop-foot by artificially contracting the tibialis anterior, and has had considerable success both clinically and commercially. However current commercial controllers are open loop and have long set-up times. The few controllers in the research domain are predominantly open-loop, lack accuracy, and struggle with muscle delays, non-linearities and the onset of fatigue. More advanced controllers require extensive sensor data and/or are highly dependent on an identified model. Recent developments have shown model based controllers combined with learning can facilitate higher accuracy, however previous attempts employed batch-wise learning, and led to disjointed control signals. This paper applies repetitive control (RC) to drop-foot for the first time, facilitating a continuous, smooth process of learning with no resetting. To maximise performance, a comprehensive extension to the traditional RC framework is undertaken to enable only isolated time points to be tracked, improving robustness and reducing memory and communication requirements. Experimental data confirms that RC can achieve normal gait when applied to FES-assisted gait with no voluntary effort. The new 'point-to-point' RC framework outperformed traditional RC, while using only 5 data points per gait cycle and minimal control effort. [ABSTRACT FROM AUTHOR]

There is increasing evidence that neuroplastic changes can occur even years after spinal cord injury, leading to reduced disability and better health which should reduce the cost of healthcare. In motor-incomplete spinal cord injury, recovery of leg function may occur if repetitive training causes afferent input to the lumbar spinal cord. The afferent input may be due to activity-based therapy without electrical stimulation but we present evidence that it is faster with electrical stimulation. This may be spinal cord stimulation or peripheral nerve stimulation. Recovery is faster if the stimulation is phasic and that the patient is trying to use their legs during the training. All the published studies are small, so all conclusions are provisional, but it appears that patients with more disability (AIS A and B) may need to continue using stimulation and for them, an implanted stimulator is likely to be convenient. Patients with less disability (AIS C and D) may make useful recovery and improve their quality of life from a course of therapy. This might be locomotion therapy but we argue that cycling with electrical stimulation, which uses biofeedback to encourage descending drive, causes rapid recovery and might be used with little supervision at home, making it much less expensive. Such an electrical therapy followed by conventional physiotherapy might be affordable for the many people living with chronic SCI. To put this in perspective, we present some information about what treatments are funded in the UK and the US. [ABSTRACT FROM AUTHOR]

Background: Osteoarthritis is a major cause of pain and disability worldwide, therefore ways of treating this condition are paramount to a successful health system. The purpose of the study was to investigate the changes in spatial-temporal gait parameters and clinical measurements following treatment with a non-invasive foot-worn biomechanical device on patients with knee osteoarthritis within the UK.Methods: A retrospective analysis was carried out on 455 patients with knee osteoarthritis. All patients were evaluated using a computerized gait test and two self-assessment questionnaires (WOMAC and SF-36) at baseline and after 3 and 6 months of treatment. The biomechanical device is a shoe-like device with convex pods under the sole that have the capability of changing foot centre of pressure and training neuromuscular control. The device was individually calibrated for each patient to minimise symptoms whilst walking and train neuromuscular control. Patients used the device for short periods during activities of daily living. Repeated measures statistical analyses were performed to compare differences over time.Results: After 6 months of treatment significant improvements were seen in all gait parameters (p < 0.01). Specifically, gait velocity, step length and single limb support of the more symptomatic knee improved by 13, 7.8 and 3%, respectively. These were supported by significant improvements in pain, function and quality of life (48.6, 45.7 and 22% respectively; p < 0.001). A sub-group analysis revealed no baseline differences between those who were recommended joint replacement and those who were not. Both groups improved significantly over time (p < 0.05 for all).Conclusions: Our results suggest that the personalised biomechanical treatment can improve gait patterns, pain, function and quality of life. It may provide an additional solution to managing UK patients suffering from knee osteoarthritis but needs to be tested in a controlled setting first. [ABSTRACT FROM AUTHOR]

Spinal cord injury is a debilitating condition associated with significant physical and emotional burden for the patients and families involved. Despite advances in care of patients following spinal cord injury, rehabilitation following injury remains an underfunded area of research that is in need of significant change. Although bed rest has been suggested to improve spinal cord perfusion after acute cord injury, there is no data to suggest that long periods of bed rest following spinal cord injury (in the absence of haemodynamic or biomechanical instability) leads to better outcome. Despite paucity of evidence, prolonged flat bed rest is still practiced in many spinal cord injury rehabilitation units across United Kingdom with no consensus on timing of mobilisation. Here we review some of the controversies on mobilisation and rehabilitation following spinal cord injury with the aim to emphasise on the benefits of early mobilisation following spinal cord injury and to challenge the old practice of long periods of flat bed rest. [ABSTRACT FROM AUTHOR]

High rates of occupational training-related lower-limb musculoskeletal (MSK) overuse injuries are reported for British Army recruits during basic training. Foot drill is a repetitive impact loading occupational activity and involves striking the ground violently with an extended-knee (straight-leg) landing. Foot drill produces vertical ground reaction force (vGRF) equal to or greater than those reported for high-level plyometric exercises/activities. Shock absorbing footwear aid in the attenuation of the magnitude of vGRF, resulting in a reduced risk of lower-limb MSK overuse injury when running. The potential shock absorbing characteristics of standard issue British Army footwear on the magnitude of vGRF and temporal parameters of foot drill are scant. Therefore, this study sought to determine the magnitude of and examine changes in vGRF and temporal parameters of foot drill across 3 types of British Army footwear. Sampled at 1,000 Hz, the mean of 8 trials from 15 recreationally active men were collected from 4 foot drills; stand-at-ease, stand-at-attention, quick-march (QM), and halt. Analysis of a normal walk was included to act as a comparison with QM. Significant main effects (P ≤ 0.05) were observed between footwear and foot drill. The training shoe (TR) demonstrated significantly greater shock absorbing capabilities when compared with the combat boot and ammunition boot. Foot drill produced peak vGRF and peak vertical rate of force development in excess of 5 bw, and 350 bw·s, respectively. Time to peak vGRF ranged from 0.016 to 0.036 ms across foot drills, indicating that passive vGRF may not be under neuromuscular control. The marginal reductions in the magnitude of vGRF and temporal parameters in foot drill associated with the TR may act to reduce the accumulative impact loading forces experienced by recruits, subsequently minimizing the severity and rates of lower-limb MSK overuse injuries and recruit medical discharges during basic training. [ABSTRACT FROM AUTHOR]

Trabecular bone structure in adulthood is a product of a process of modelling during ontogeny and remodelling throughout life. Insight into ontogeny is essential to understand the functional significance of trabecular bone structural variation observed in adults. The complex shape and loading of the human calcaneus provides a natural experiment to test the relationship between trabecular morphology and locomotor development. We investigated the relationship between calcaneal trabecular bone structure and predicted changes in loading related to development of gait and body size in growing children. We sampled three main trabecular regions of the calcanei using micro‐computed tomography scans of 35 individuals aged between neonate to adult from the Norris Farms #36 site (1300 AD, USA) and from Cambridge (1200–1500 AD, UK). Trabecular properties were calculated in volumes of interest placed beneath the calcaneocuboid joint, plantar ligaments, and posterior talar facet. At birth, thin trabecular struts are arranged in a dense and relatively isotropic structure. Bone volume fraction strongly decreases in the first year of life, whereas anisotropy and mean trabecular thickness increase. Dorsal compressive trabecular bands appear around the onset of bipedal walking, although plantar tensile bands develop prior to predicted propulsive toe‐off. Bone volume fraction and anisotropy increase until the age of 8, when gait has largely matured. Connectivity density gradually reduces, whereas trabeculae gradually thicken from birth until adulthood. This study demonstrates that three different regions of the calcaneus develop into distinct adult morphologies through varying developmental trajectories. These results are similar to previous reports of ontogeny in human long bones and are suggestive of a relationship between the mechanical environment and trabecular bone architecture in the human calcaneus during growth. However, controlled experiments combined with more detailed biomechanical models of gait maturation are necessary to establish skeletal markers linking growth to loading. This has the potential to be a novel source of information for understanding loading levels, activity patterns, and perhaps life history in the fossil record. [ABSTRACT FROM AUTHOR]

Background: The plantaris tendon (PT) has been thought to contribute to symptoms in a proportion of patients with Achilles midportion tendinopathy, with symptoms improving after PT excision. Hypothesis: There is compression and differential movement between the PT and Achilles tendon (AT) during ankle plantarflexion and dorsiflexion. Study Design: Descriptive laboratory study. Methods: Eighteen fresh-frozen cadaveric ankles (mean ± SD age: 35 ± 7 years, range = 27-48 years; men, n = 9) were mounted in a customized testing rig, where the tibia was fixed but the forefoot could be moved freely. A Steinmann pin was drilled through the calcaneus, enabling a valgus torque to be applied. The soleus, gastrocnemius, and plantaris muscles were loaded with 63 N with a weighted pulley system. The test area was 40 to 80 mm above the os calcis, corresponding to where the injury is observed clinically. Medially, the AT and PT were exposed, and a calibrated flexible pressure sensor was inserted between the tendons. Pressure readings were recorded with the ankle in full dorsiflexion, full plantarflexion, and plantargrade and repeated in these positions with a 5 N·m torque, simulating increased hindfoot valgus. The pressure sensor was removed and the PT and AT marked with ink at the same level, with the foot held in neutral rotation and plantargrade. Videos and photographs were taken to assess differential motion between the tendons. After testing, specimens were dissected to identify the PT insertion. One-way analysis of variance and paired t tests were performed to make comparisons. Results: The PT tendons with an insertion separate from the AT demonstrated greater differential motion through range (14 ± 4 mm) when compared with those directly adherent to the AT (2 ± 2 mm) (P < .001). Mean pressure between the PT and AT rose in terminal plantarflexion for all specimens (P < .001) and was more pronounced with hindfoot valgus (P < .001). Conclusion: The PT inserting directly into the calcaneus resulted in significantly greater differential motion as compared with the AT. Tendon compression was elevated in terminal plantarflexion, suggesting that adapting rehabilitation tendon-loading programs to avoid this position may be beneficial. Clinical Relevance: The insertion pattern of the PT may be a factor in plantaris-related midportion Achilles tendinopathy. Terminal range plantarflexion and hindfoot valgus both increased AT and PT compression, suggesting that these should be avoided in this patient population. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse lower limb work patterns in world-class race walkers. Seventeen male and female athletes race walked at competitive pace. Ground reaction forces (1000 Hz) and highspeed videos (100 Hz) were recorded and normalised joint moments, work and power, stride length, stride frequency and speed estimated. The hip flexors and extensors were the main generators of energy (24.5 J (±6.9) and 40.3 J (±8.3), respectively), with the ankle plantarflexors (16.3 J (±4.3)) contributing to the energy generated during late stance. The knee generated little energy but performed considerable negative work during swing (-49.1 J (±8.7)); the energy absorbed by the knee extensors was associated with smaller changes in velocity during stance (r = .783, P < .001), as was the energy generated by the hip flexors (r = -.689, P = .002). The knee flexors did most negative work (-38.6 J (±5.8)) and the frequent injuries to the hamstrings are probably due to this considerable negative work. Coaches should note the important contributions of the hip and ankle muscles to energy generation and the need to develop knee flexor strength in reducing the risk of injury. [ABSTRACT FROM AUTHOR]

Slip-induced falls are among the most common cause of major occupational injuries in the UK as well as being a major public health concern in the elderly population. This study aimed to determine the optimal fall indicators for fall detection models which could be used to reduce the detrimental consequences of falls. A total of 264 kinematic variables covering three-dimensional full body model translation and rotational measures were analysed during normal walking, successful recovery from slips and falls on a cross-slope. Large effect sizes were found for three kinematic variables which were able to distinguish falls from normal walking and successful recovery. Further work should consider other types of daily living activities as results show that the optimal kinematic fall indicators can vary considerably between movement types. Practitioner Summary: Fall detection models are used to minimise the adverse consequences of slip-induced falls, a major public health concern. Optimal fall indicators were derived from a comprehensive set of kinematic variables for slips on a cross-slope. Results suggest robust detection of falls is possible on a cross-slope but may be more difficult than level walking. [ABSTRACT FROM AUTHOR]

Cyclic and noncyclic breast pain effect up to 60% of women, decreasing the quality of life. In addition, exercise-induced breast pain (thought to be caused by tension on breast skin and fascia during breast motion) is reported in up to 72% of exercising females. These forms of breast pain may be experienced concurrently; therefore, it is hypothesized that this compound effect may cause higher breast pain prevalence and severity in active populations. This study investigated the prevalence and severity of breast pain in an active cohort, compared to a random cohort. A random sample of 234 UK females completed a self-administered survey reporting physical activity history, prevalence, severity and frequency of breast pain, breast support habits, bra satisfaction, occurrence of bra-related issues, and demographics. This sample was age-matched to a sample of active females ( n = 234) from a cross-sectional survey of 1,285 female marathon runners who completed a similar survey. Breast pain prevalence was significantly lower in the active cohort (32.1%) compared to the random cohort (43.6%), however, the severity and frequency of breast pain was similar in both cohorts. Females in the active cohort undertook significantly more physical activity, were lighter, had greater nulliparous rates, greater adherence to sports bra use, but less adherence to professional bra fitting. With lower breast pain rates in the active cohort the hypothesis of a compound effect of multiple forms of breast pain causing an increase in prevalence and severity is rejected. The lower prevalence may be related to increased physical activity, reduced body mass, and increased sports bra use. Sports bra use is already recommended in the literature for symptomatic women, however, this is the first study to report that increased physical activity and weight loss may be an appropriate life style choice to reduce the prevalence of breast pain. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the age-based, lower limb kinetics of running performances of endurance athletes. Six running trials were performed by 24 male athletes, who were distinguished by three age groupings (S35: 26–32 years, M50: 50–54 years, M60+: 60–68 years). Lower limb coordinate and ground reaction force data were collected using a nine camera infra-red system synchronised with a force plate. A slower anteroposterior (M ± SD S35 = 4.13 ± 0.54 m/s: M60+ = 3.34 ± 0.40 m/s,p < 0.05) running velocity was associated with significant (p < 0.05) decreases in step length and discrete vertical ground contact force between M60+and S35 athletes. The M60+athletes simultaneously generated a 32% and 42% reduction (p < 0.05) in ankle joint moment when compared to the M50 and S35 athletes and 72% (p < 0.05) reduction in knee joint stiffness when compared to S35 athletes. Age-based declines in running performance were associated with reduced stance phase force tolerance and generation that may be accounted for due to an inhibited force–velocity muscular function of the lower limb. Joint-specific coaching strategies customised to athlete age are warranted to maintain/enhance athletes' dynamic performance. [ABSTRACT FROM PUBLISHER]

Breast asymmetry is common in females, despite a similar driving force; dynamic activity may result in asymmetrical breast motion. This preliminary study investigated how breast categorisation (left/right or dominant/non-dominant) may affect breast support recommendations and its relationship with breast pain. Ten females ran on a treadmill at 10 kph in three breast supports (no bra, everyday bra, sports bra). Five reflective markers on the thorax and nipples were tracked using infrared cameras (200 Hz) during five running gait cycles in each breast support. Multiplanar displacements of both breasts were calculated relative to the thorax. Although the maximum individual participant difference was 2.4 cm (mediolaterally) between the left and right breast, no left/right differences were found in any direction or support condition. Notably, correlations between breast pain and anterioposterior breast displacement were stronger with the left breast (r = 0.614) and moderate with the right breast (r = 0.456). Following participant categorisation according to the greatest magnitude of superioinferior breast displacement (dominant breast), results showed significant differences in displacement for all directions across different breast supports. When using breast kinematic data to examine relationships with breast pain or to recommend breast support requirements, data on both breasts should be collected. [ABSTRACT FROM AUTHOR]

Background and purpose - Ceramic-on-ceramic (CoC) bearings have been in use in total hip replacement (THR) for more than 40 years, with excellent long-term survivorship. Although there have been several simulator studies describing the performance of these joints, there have only been a few retrieval analyses. The aim of this study was to investigate the wear patterns, the surface properties, and friction and lubrication regimes of explanted first-generation alumina bearings. Materials and methods - We studied 9 explanted CoC bearings from Autophor THRs that were revised for aseptic loosening after a mean of 16 (range 7-19) years. The 3D surface roughness profiles of the femoral heads and acetabular cups (Srms, Sa, and Ssk) were measured to determine the microscopic wear. The bearings were imaged using an atomic-force microscope in contact mode, to produce a topographical map of the surfaces of the femoral heads. Friction tests were performed on the bearing couples to determine the lubrication regime under which they were operating during the walking cycle. The diametral clearances were also measured. Results - 3 femoral heads showed stripe wear and the remaining 6 bearings showed minimal wear. The femoral heads with stripe wear had significantly higher surface roughness than the minimally worn bearings (0.645 vs. 0.289, p = 0.04). High diametral clearances, higher than expected friction, and mixed/boundary lubrication regimes prevailed in these retrieved bearings. Interpretation - Despite the less than ideal tribological factors, these first-generation CoC bearings still showed minimal wear in the long term compared to previous retrieval analyses. [ABSTRACT FROM AUTHOR]

The treadmill is an attractive device for the investigation of human locomotion, yet the extent to which lower limb kinematics differ from overground running remains a controversial topic. This study aimed to provide an extensive three-dimensional kinematic comparison of the lower extremities during overground and treadmill running. Twelve participants ran at 4.0 m/s ( ± 5%) in both treadmill and overground conditions. Angular kinematic parameters of the lower extremities during the stance phase were collected at 250 Hz using an eight-camera motion analysis system. Hip, knee, and ankle joint kinematics were quantified in the sagittal, coronal, and transverse planes, and contrasted using pairedt-tests. Of the analysed parameters hip flexion at footstrike and ankle excursion to peak angle were found to be significantly reduced during treadmill running by 12° (p = 0.001) and 6.6° (p = 0.010), respectively. Treadmill running was found to be associated with significantly greater peak ankle eversion (by 6.3°,p = 0.006). It was concluded that the mechanics of treadmill running cannot be generalized to overground running. [ABSTRACT FROM PUBLISHER]

Cardan/Euler and helical angles are the popular methods of quantifying angular kinematics. Cardan angles are sequence dependent and crosstalk can influence the kinematic calculations. The International Society of Biomechanics (ISB) recommends a sagittal, coronal, and then transverse (XYZ) sequence of rotations, although it has been proposed that when calculating rotations outside of the sagittal plane, this may not be the most appropriate method. This study investigated the influence of the helical and six available Cardan sequences on three-dimensional (3D) ankle joint kinematics. Kinematic data were obtained using an eight-camera motion analysis system as participants ran at 4.0 m/s ± 5%. Repeated measures ANOVAs were used to compare kinematic parameters, and intra-class correlations were employed to identify evidence of crosstalk across planes. The results indicate that in the transverse and coronal planes, peak angle and range of motion values using the YXZ and ZXY sequences were significantly greater than the other sequences. Furthermore, utilization of YXZ and ZXY sequences was associated with the strongest correlations from the sagittal plane, and the XYZ sequence was found to be associated with the lowest correlations. It appears that for the representation of 3D ankle joint kinematics, the XYZ sequence is associated with minimal planar crosstalk and as such its use is encouraged. [ABSTRACT FROM AUTHOR]

Background and Purpose Despite the finding that 40% to 60% of stroke patients suffer from knee joint hyperextension during gait, there is a lack of agreement of the possible causes of this problem. The aim of this study was to determine whether there is a relationship between lower limb muscle weakness and knee joint hyperextension in hemiparetic stroke patients. Methods This is a cross-sectional observational comparison study. Twenty patients (mean age 66 years) who had suffered a single hemiparetic stroke and were ambulant with no major lower limb joint pathology participated. Muscle strength of the hip extensors, hip flexors, hip abductors, knee extensors, knee flexors, ankle plantarflexors and ankle dorsiflexors of both limbs was measured using a hand-held dynamometer. Computerized and visual gait analysis identified subjects with and without knee hyperextension in loading response and midstance. Subjects were categorized as having weakness of a particular muscle group if the difference in strength between the paretic and non-paretic muscle was greater than 50%. The Pearson's chi-squared test was used to evaluate the association between weakness and knee hyperextension. Results A strong relationship was found between ankle plantarflexor weakness and knee hyperextension during midstance ( p = 0.044). No relationship was found between lower limb muscle weakness and knee hyperextension during loading response ( p > 0.05). No relationship was found between any other lower limb muscle groups and knee hyperextension in midstance ( p > 0.05). Conclusions Weak ankle plantarflexors, in particular gastrocnemius, may have an important role in the presence of knee hyperextension. The results of this study did not support a role for weak hamstrings or quadriceps in knee hyperextension during gait. Further research is needed to clarify the role of gastrocnemius during the stance phase and to determine if strengthening weak gastrocnemius reduces knee hyperextension. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the important kinematic variables in elite men's and women's 20 km race walking. Thirty men and 30 women were analysed from video data recorded during the World Race Walking Cup. Video data were also recorded at four points during the European Cup Race Walking and 12 men and 12 women analysed from these data. Two camcorders operating at 50 Hz recorded at each race for 3D analysis. The two main performance determinants of speed were step length and cadence. Men were faster than women because of their greater step lengths but there was no difference in cadence. A reduction in step length was the initial cause of slowing down with later decreases in speed caused by reductions in cadence. Shorter contact times were important in optimising both step length and cadence, and faster athletes tended to have longer flight times than slower athletes. It was less clear which other kinematic variables were critical for successful walking, particularly with regard to joint angles. Different associations were found for some key variables in men and women, suggesting that their techniques may differ due to differences in height and mass. [ABSTRACT FROM AUTHOR]

Lymphoedema is a chronic progressive condition of the lymphatic system. It occurs because of poor lymphatic drainage of an area of the body leading to an increase in interstitial volume secondary to a build up of lymphatic fluid, and chronic oedema (Lymphoedema Framework, 2006; Tiwari A, et al 2003). Lymphoedema may affect any part of the body but the arms and legs are the most common sites. It is estimated that there are at least 100 000 sufferers in the UK alone (Moffat C et al, 2003). This article seeks to look at the importance of appropriate footwear in patients with chronic swelling caused by lymphoedema and takes a look at some of the practical problems encountered with footwear in clinical practice. [ABSTRACT FROM AUTHOR]

This article presents abstracts of the papers presented at the 2006 Annual Conference of the British Association of Sport and Exercise Sciences, held at the University of Wolverhampton in Great Britain. The paper "Joint power and work in an elite sprinter at maximum velocity," by I. N. Bezodis, A. I. T. Salo and D. G. Kerwin, is summarized. The article "Relationships between kinetic and kinematic variables during distance running," by B. Hanley and A. Mohan, is also abstracted. The article "Test-retest stability of mood measures," by A.M. Lane and A. Nevill, is also summarized.

Objective: To assess the effect of different aids on the amount of support hemiplegic subjects took from them. The relationship between the amount of support, severity of hemiplegia and walking ability were also assessed. Design: Hemiplegic subjects’ gait and the amount of support they took from the aid were measured as they walked with a normal height stick, a high stick and a tripod. Subjects: Fifteen subjects with a hemiplegia of more than three months’ duration who could walk independently were recruited. Outcome measures: Velocity, the gross function section of the Rivermead Motor Assessment, percentage bodyweight taken through the aid, the aid contact time, the placement of the aid, and the lateral shift of the pelvis when weight bearing were assessed. Results: No differences in the amount of support or walking ability were found with the different aids. There was a significant relationship between severity of hemiplegia and the percentage of bodyweight taken through the aid (r &equals; -0.67), between aid contact time and severity of hemiplegia (-0.53) and between aid contact time and walking ability (-0.53). No relationship between walking ability and other measures of the amount of support was found. Conclusions: Different types of aid did not influence the amount of support taken by hemiplegic subjects. These results contradict the beliefs of many neurological physiotherapists in Britain and the clinical implications are discussed. [ABSTRACT FROM AUTHOR]

This article presents several studies related to rheumatology in children. Musculoskeletal problems are common in children and adolescents. In many cases symptoms are not volunteered. Performance of a competent musculoskeletol examination, with recognition of age-related variation, is essential for all clinicians caring for children and adolescents to facilitate prompt referral, diagnosis and management. Pediatric musculoskeletal examination is not a core requirement in most Great Britain medical schools and so clinicians may need to seek information from textbooks. There are no previously published large studies of childhood peripheral bone mineral density (BMD). This study was designed to produce data which could be used as a reference For children who have conditions known to alter BMD.

Background: Visual information comprises one of the most salient sources of information used to control walking and the dependence on vision to maintain dynamic stability increases following a stroke. We hypothesize, therefore, that rehabilitation efforts incorporating visual cues may be effective in triggering recovery and adaptability of gait following stroke. This feasibility trial aims to estimate probable recruitment rate, effect size, treatment adherence and response to gait training with visual cues in contrast to conventional overground walking practice following stroke.Methods/design: A 3-arm, parallel group, multi-centre, single blind, randomised control feasibility trial will compare overground visual cue training (O-VCT), treadmill visual cue training (T-VCT), and usual care (UC). Participants (n = 60) will be randomly assigned to one of three treatments by a central randomisation centre using computer generated tables to allocate treatment groups. The research assessor will remain blind to allocation. Treatment, delivered by physiotherapists, will be twice weekly for 8 weeks at participating outpatient hospital sites for the O-VCT or UC and in a University setting for T-VCT participants.Individuals with gait impairment due to stroke, with restricted community ambulation (gait speed <0.8m/s), residual lower limb paresis and who are able to take part in repetitive walking practice involving visual cues (i.e., no severe visual impairments, able to walk with minimal assistance and no comorbid medical contraindications for walking practice) will be included.The primary outcomes concerning participant enrolment, recruitment, retention, and health and social care resource use data will be recorded over a recruitment period of 18 months. Secondary outcome measures will be undertaken before randomisation (baseline), after the eight-week intervention (outcome), and at three months (follow-up). Outcome measures will include gait speed and step length symmetry; time and steps taken to complete a 180° turn; assessment of gait adaptability (success rate in target stepping); timed up and go; Fugl-Meyer lower limb motor assessment; Berg balance scale; falls efficacy scale; SF-12; and functional ambulation category.Discussion: Participation and compliance measured by treatment logs, accrual rate, attrition, and response variation will determine sample sizes for an early phase randomised controlled trial and indicate whether a definitive late phase efficacy trial is justified.Trial Registration: Clinicaltrials.gov, NCT01600391. [ABSTRACT FROM AUTHOR]