Ankle instability effects on joint position sense when stepping across the active movement extent discrimination apparatus

CONTEXT: Individuals with and without functional ankle instability have been tested for deficits in lower limb proprioception with varied results. OBJECTIVE: To determine whether a new protocol for testing participants' joint position sense during stepping is reliable and can detect differences between participants with unstable and stable ankles. DESIGN: Descriptive laboratory study. SETTING: University clinical laboratory. PATIENTS OR OTHER PARTICIPANTS: Sample of convenience involving 21 young adult university students and staff. Ankle stability was categorized by score on the Cumberland Ankle Instability Tool; 13 had functional ankle instability, 8 had healthy ankles. INTERVENTION(S): Test-retest of ankle joint position sense when stepping onto and across the Active Movement Extent Discrimination Apparatus twice, separated by an interim test, standing still on the apparatus and moving only 1 ankle into inversion. MAIN OUTCOME MEASURE(S): Difference in scores between groups with stable and unstable ankles and between test repeats. RESULTS: Participants with unstable ankles were worse at differentiating between inversion angles underfoot in both testing protocols. On repeated testing with the stepping protocol, performance of the group with unstable ankles was improved (Cohen d = 1.06, P = .006), whereas scores in the stable ankle group did not change in the second test (Cohen d = 0.04, P = .899). Despite this improvement, the unstable group remained worse at differentiating inversion angles on the stepping retest (Cohen d = 0.99, P = .020). CONCLUSIONS: The deficits on proprioceptive tests shown by individuals with functional ankle instability improved with repeated exposure to the test situation. The learning effect may be the result of systematic exposure to ankle-angle variation that led to movement-specific learning or increased confidence when stepping across the apparatus

Altered movement patterns but not muscle recruitment in moderately trained triathletes during running after cycling

Previous studies have shown that cycling can directly influence neuromuscular control during subsequent running in some highly trained triathletes, despite these triathletes\u27 years of practice of the cycle-run transition. The aim of this study was to determine whether cycling has the same direct influence on neuromuscular control during running in moderately trained triathletes. Fifteen moderately trained triathletes participated. Kinematics of the pelvis and lower limbs and recruitment of 11 leg and thigh muscles were compared between a control run (no prior exercise) and a 30 min run that was preceded by a 15 min cycle (transition run). Muscle recruitment was different between control and transition runs in only one of 15 triathletes (&lt;7%). Changes in joint position (mean difference of 3&deg;) were evident in five triathletes, which persisted beyond 5 min of running in one triathlete. Our findings suggest that some moderately trained triathletes have difficulty reproducing their pre-cycling movement patterns for running initially after cycling, but cycling appears to have little influence on running muscle recruitment in moderately trained triathletes. <br /

REPEATABILlTY OF INTRAMUSCULAR ELECTROMYOGRAPHIC RECORDINGS DURING CYCLING

Fine-wire electromyographic (fEMG) techniques are indicated for the study of distal lower limb muscle recruitment during cycling, but evidence to support the repeatability of fEMG recordings is contradictory. This study investigated the repeatability of fEMG recordings from tibialis anterior (TA), tibialis posterior (TP), peroneus longus (PL), gastrocnemius lateralis (GL) and soleus (SOL) during cycling. The repeatability of fEMG recordings normalised to maximum measured EMG amplitude was high, with mean coefficients of multiple correlation (CMC) ranging from .82 .15 (GL) to .89 .09 (TA). The repeatability of fEMG recordings increased with greater test-retest intervals (p < .008). Data normalised to maximal or submaximal contractions were less repeatable (p < .001). These findings support the use of fEMG techniques to investigate distal lower limb muscle recruitment during cycling

MULTIDISCIPLlNE TRAINING DEMANDS MAY IMPAIR ADAPTATION OF THE NEUROMUSCULAR SYSTEM IN TRIATHLETES

Muscle recruitment during cycling is highly consistent and constrained in trained cyclists relative to novice cyclists (Chapman et aI., 2004). This is consistent with previous evidence that adaptation of the neuromuscular system occurs with repeated performance of a motor task. Muscle recruitment in triathletes has not been investigated. Triathletes undertake similar cycling training loads to specialist cyclists, but must also undertake very high running and swimming training loads. The influence of these multidiscipline training demands on muscle recruitment remains unknown. This study compared patterns of distal lower limb muscle recruitment during cycling in triathletes, trained cyclists and novice cyclists

Neuromuscular control and running economy is preserved in elite international triathletes after cycling

Running is the most important discipline for Olympic triathlon success. However, cycling impairs running muscle recruitment and performance in some highly trained triathletes; though it is not known if this occurs in elite international triathletes. The purpose of this study was to investigate the effect of cycling in two different protocols on running economy and neuromuscular control in elite international triathletes. Muscle recruitment and sagittal plane joint angles of the left lower extremity and running economy were compared between control (no preceding cycle) and transition (preceded by cycling) runs for two different cycle protocols (20-minute low-intensity and 50-minute high-intensity cycles) in seven elite international triathletes. Muscle recruitment and joint angles were not different between control and transition runs for either cycle protocols. Running economy was also not different between control and transition runs for the ow-intensity (62.4 ^ 4.5 vs. 62.1 ^ 4.0 ml/min/kg, p . 0.05) and high-intensity (63.4 ^ 3.5 vs. 63.3 ^ 4.3 ml/min/kg, p . 0.05) cycle protocols. The results of this study demonstrate that both low- and high-intensity cycles do not adversely influence neuromuscular control and running economy in elite international triathletes.<br /

The UK paediatric ocular trauma study 2 (POTS2):Demographics and mechanisms of injuries

Freda Sii,1,2 Robert J Barry,1 Joseph Abbott,3 Richard J Blanch,1,4 Caroline J MacEwen,5 Peter Shah1,2,6,7 1Department of Ophthalmology, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham NHS Foundation Trust, Birmingham, 2Birmingham Institute for Glaucoma Research, Institute of Translational Medicine, University Hospitals Birmingham NHS Foundation Trust, Birmingham, 3Department of Ophthalmology, Birmingham Children&rsquo;s Hospital NHS Foundation Trust, Birmingham, 4Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Birmingham, 5Department of Ophthalmology, Ninewells Hospital and Medical School, Dundee, 6National Institute of Health Research Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, 7Centre for Health and Social Care Improvement, School of Health and Wellbeing, University of Wolverhampton, Wolverhampton, UK Purpose: Pediatric ocular trauma is an important cause of visual morbidity worldwide, accounting for up to one-third of all ocular trauma admissions. It has long-term implications for those affected and significant economic consequences for healthcare providers. It has been estimated that 90% of all ocular trauma is preventable. Targeted strategies are required to reduce the incidence and the severity of pediatric ocular trauma; this requires an understanding of the epidemiology and characteristics of these injuries and the children involved. Methods: Prospective, observational study of pediatric ocular trauma cases presenting to UK-based ophthalmologists over a 1-year period; reporting cards were distributed by the British Ophthalmological Surveillance Unit, and clinicians were asked to report incidents of acute orbital and ocular trauma in children aged &le;16 years requiring inpatient or day-case admission. A validated, standardized questionnaire was sent to reporting ophthalmologists to collect data on the demographics and circumstances of injury. Results: Median age at presentation was 7.7 years, with boys more than twice as likely to be affected than girls (M:F =2.1:1.0). Almost 50% of injuries occurred at home, with 25% occurring in school or nursery. A total of 67% of injuries occurred during play, and 31% involved a sharp implement. Conclusion: Pediatric ocular trauma remains an important public health problem. At least three-quarters of all injuries are preventable through measures, including education of children and responsible adults, restricting access to sharp implements, improving adult supervision, and appropriate use of eye protection. Keywords: etiology, childhood eye injury, epidemiology, penetrating eye injury, perforating eye injury, preventio

The UK Paediatric Ocular Trauma Study 1 (POTS1):development of a global standardized protocol for prospective data collection in pediatric ocular trauma

Freda Sii,1,2 Robert J Barry,1 Richard J Blanch,1 Joseph Abbott,3 Caroline J MacEwen,4 Peter Shah1,2,5,6 1Department of Ophthalmology, Queen Elizabeth Hospital Birmingham, 2Birmingham Institute for Glaucoma Research, Institute of Translational Medicine, University Hospitals Birmingham NHS Foundation Trust, 3Department of Ophthalmology, Birmingham Children&rsquo;s Hospital NHS Foundation Trust, Birmingham, 4Department of Ophthalmology, Ninewells Hospital and Medical School, Dundee, 5National Institute of Health Research Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, 6Centre for Health and Social Care Improvement, School of Health and Wellbeing, University of Wolverhampton, Wolverhampton, UK Background: Ocular trauma is an important cause of visual morbidity in children worldwide. Pediatric ocular trauma accounts for up to one third of all ocular trauma admissions, with significant economic implications for health care providers. It is estimated that 90% of all ocular trauma is preventable. Development of strategies to reduce the incidence and severity of pediatric ocular trauma requires an understanding of the epidemiology of these injuries and their characteristics. This will enable appropriate targeting of resources toward prevention and allow effective service planning. At present, there is no standardized methodology for the collection of global cross-sectional data in pediatric ocular trauma, and the ability to undertake detailed epidemiological and health-economic analyses is limited. Furthermore, it is difficult to draw international comparisons in incidence, etiology, and outcomes of pediatric ocular trauma due to the range of published reporting criteria. This study describes two novel questionnaires for standardized data collection in pediatric ocular trauma, which can be adopted across a range of health care settings internationally.Methods: Two standardized data collection questionnaires have been developed from previously reported templates. The first enables collection of demographic and incident data on serious pediatric ocular trauma requiring hospitalization, and the second enables follow-up outcome data collection. Both the questionnaires are designed to collect primarily categorical data in order to increase ease of completion and facilitate quantitative analysis. These questionnaires enable acquisition of standardized data on the incidence, etiology, and outcomes of pediatric ocular trauma.Discussion: These questionnaires enable collection of standardized data and are designed for global use across all health care settings. Through prospective data collection, epidemiological trends can be determined, allowing health care providers to develop collaborative global preventive strategies. Furthermore, the same questionnaires may be used in future studies to draw comparisons with baseline data, allowing assessment of the efficacy of targeted preventative interventions. Keywords: childhood eye injury, epidemiology, health economic analyses, international standardization, penetrating eye injury, perforating eye injury, preventio

Match high-speed running distances are often suppressed following return from hamstring strain injury in professional footballers

Background: High-speed running is commonly implicated in the genesis of hamstring injury. The success of hamstring injury management is typically quantified by the duration of time loss or reinjury rate. These metrics do not consider any loss in performance after returning to play from hamstring injury. It is not known to what extent high-speed running is altered on return to play after such injury. Hypothesis: Match high-speed running distance will change after returning from hamstring injury. Study Design: Non-randomized cohort. Level of Evidence: Level 3. Methods: Match high-speed running distance in highest level professional football (soccer, Rugby League, Rugby Union, and Australian Rules) were examined for a minimum of 5 games prior and subsequent to hamstring strain injury for individual differences using a linear regression models approach. A total of 22 injuries in 15 players were available for analysis. Results: Preinjury cumulative high-speed running distances were strongly correlated for each individual (r2 = 0.92-1.0; P < 0.0001). Pre- and postinjury high-speed running data were available for a median of 15 matches (range, 6-15). Variance from the preinjury high-speed running distance was significantly less (P = 0.0005) than the post injury values suggesting a suppression of high-speed running distance after returning from injury. On return to play, 7 of the 15 players showed a sustained absolute reduction in preinjury high-speed running distance, 7 showed no change, and 1 player (only) showed an increase. Analysis of subsequent (second and third injury) return to play showed no differences to return from the index injury. Conclusion: Return to play was not associated with return to high-speed running performance for nearly half of the players examined, although the same number showed no difference. Persisting deficits in match high-speed running may exist for many players after hamstring strain injury. Clinical Relevance: Returning to play does not mean returning to (high-speed running) performance for nearly half of the high-level professional football players examined in this study. This suggests that successful return to play metrics should be expanded from simple time taken and recurrence to include performance

The relationship between variables in wearable microtechnology devices and cricket fast-bowling intensity

To date, the monitoring of fast-bowling workloads across training and competition environments has been limited to counting total balls bowled. However, bowling at faster velocities is likely to require greater effort while also placing greater load on the bowler. This study investigated the relationship between prescribed effort and microtechnology outputs in fast bowlers to ascertain whether the technology could provide a more refined measure of workload. Twelve high-performing fast bowlers (mean ± SD age 20.3 ± 2.2 y) participated in the study. Each bowler bowled 6 balls at prescribed bowling intensities of 60%, 70%, 85%, and 100%. The relationships between microtechnology outputs, prescribed intensity, and ball velocity were determined using polynomial regression. Very large relationships were observed between prescribed effort and ball velocity for peak PlayerLoad™ (R = .83 ± .19 and .82 ± .20). The PlayerLoad across lower ranges of prescribed effort exhibited a higher coefficient of variation (CV) (60% = 19.0% [17.0–23.0%]), while the CV at higher ranges of prescribed effort was lower (100% = 7.3% [6.4–8.5%]). Routinely used wearable microtechnology devices offer opportunities to examine workload and intensity in cricket fast bowlers outside the normal metrics reported. They offer a useful tool for prescribing and monitoring bowling intensity and workload in elite fast bowlers