Fixation failure in an isolated tibial eminence ACL traction avulsion fracture in a paratrooper: is there an association with vitamin D deficiency?

Tibial eminence avulsion fracture at the ACL footprint may be caused by high-energy forces such as a fall, in which the ACL ligament proves stronger than the forces that hold the bone together. For reasons of bone maturity however, tibial spine avulsion fractures where the ACL remains intact, typically occur in children but are rare in adults. This case demonstrates a rare type of adult tibial avulsion fracture with intact ACL and subsequent fragment fixation failure in which vitamin D deficiency may have been contributory. Because there is a high rate of inadequate vitamin D levels in patients undergoing orthopaedic surgery and a known impact on bone healing complications, post-operative bone fixation failure may also occur. This case report may therefore prompt further awareness for considering pre-surgical vitamin D deficiency screening in adults presenting with rare avulsion fractures, and may further demonstrate its impact on surgical outcomes

Predictors of shuttle walking test performance in patients with cardiovascular disease

Objective: The incremental shuttle walking test (ISWT) is used to estimate cardiorespiratory fitness, but data from healthy individuals suggest that demographic and anthropometric measures account for much of the variance in test performance. The aim of this study was to determine whether anthropometric, demographic and selected gait measures also predict ISWT performance (i.e. distance walked) in patients with cardiovascular disease. Design: Observational study. Setting: A community-based cardiac rehabilitation centre (Cohort 1) and a hospital outpatient cardiac rehabilitation programme (Cohort 2). Participants: Sixteen patients with clinically stable cardiovascular disease (Cohort 1) and 113 patients undergoing cardiac rehabilitation (Cohort 2). Interventions: Patients in Cohort 1 performed the ISWT on two occasions. Anthropometric data and walking and turning variables were collected. Linear regression analyses were used to identify the predictors of test performance. The authors subsequently attempted to validate the equation created by comparing predicted and actual ISWT values in a larger (n= 113) validation sample (Cohort 2). Main outcome measures: Distance walked during ISWT, step length and height. Results: No gait or turning measures were significantly associated with ISWT performance. Distance walked correlated most strongly with step length (r= 0.83, P< 0.05) and height (r= 0.74, P< 0.05). Given the similarity of these correlations and the rarity of step length assessment in clinical practice, ISWT performance was predicted using patient's height; this explained 55% of the variance in ISWT performance. Height was also the best predictor in Cohort 2, explaining 17% of test variance (P< 0.01). Body mass index explained an additional 3% of variance (P< 0.05) in ISWT performance. Conclusions: Routine clinical measures, particularly patient's height, are predictive of ISWT performance. The findings of the present study are in partial agreement with similar studies performed in healthy individuals, and it remains unclear whether the ISWT performance of patients with cardiovascular disease is influenced by the same factors as the ISWT performance of healthy individuals. © 2013

Are there associations with age and sex in walking stability in healthy older adults?

The variability of the centre of pressure (COP) during walking can provide information in relation to stability when walking. The aim of this study was to investigate if age and sex were associated with COP variability, COP excursions, and COP velocities during walking. One-hundred and fourteen older adults (age 65.1 ± 5.5 yrs.) participated in the study. A Kistler force platform (1000 Hz) recorded the ground reaction forces and COPs during walking at a self-selected walking speed. The stance phase was divided, using the vertical GRF, into four sub-phases: loading response (LR), mid-stance (MSt), terminal stance (TSt), and pre-swing (PSw). The standard deviations of the COP displacement (variability), the COP velocity, and COP excursion in the medial–lateral and anterior–posterior directions, as well as the resultant magnitude were assessed. When controlling for walking speed, a greater age was associated with a higher variability and excursion of the COP during LR only suggesting that stability is maintained during the majority of the stance phase. During LR lower COP velocity was significantly associated for females for anterior-posterior and total COP, which may be a strategy to facilitate stability before, and moving into, MSt and TSt

Caenorhabditis briggsae Recombinant Inbred Line Genotypes Reveal Inter-Strain Incompatibility and the Evolution of Recombination

The nematode Caenorhabditis briggsae is an emerging model organism that allows evolutionary comparisons with C. elegans and exploration of its own unique biological attributes. To produce a high-resolution C. briggsae recombination map, recombinant inbred lines were generated from reciprocal crosses between two strains and genotyped at over 1,000 loci. A second set of recombinant inbred lines involving a third strain was also genotyped at lower resolution. The resulting recombination maps exhibit discrete domains of high and low recombination, as in C. elegans, indicating these are a general feature of Caenorhabditis species. The proportion of a chromosome's physical size occupied by the central, low-recombination domain is highly correlated between species. However, the C. briggsae intra-species comparison reveals striking variation in the distribution of recombination between domains. Hybrid lines made with the more divergent pair of strains also exhibit pervasive marker transmission ratio distortion, evidence of selection acting on hybrid genotypes. The strongest effect, on chromosome III, is explained by a developmental delay phenotype exhibited by some hybrid F2 animals. In addition, on chromosomes IV and V, cross direction-specific biases towards one parental genotype suggest the existence of cytonuclear epistatic interactions. These interactions are discussed in relation to surprising mitochondrial genome polymorphism in C. briggsae, evidence that the two strains diverged in allopatry, the potential for local adaptation, and the evolution of Dobzhansky-Muller incompatibilities. The genetic and genomic resources resulting from this work will support future efforts to understand inter-strain divergence as well as facilitate studies of gene function, natural variation, and the evolution of recombination in Caenorhabditis nematodes

Identifying associations between diabetes and acute respiratory distress syndrome in patients with acute hypoxemic respiratory failure: an analysis of the LUNG SAFE database

Background: Diabetes mellitus is a common co-existing disease in the critically ill. Diabetes mellitus may reduce the risk of acute respiratory distress syndrome (ARDS), but data from previous studies are conflicting. The objective of this study was to evaluate associations between pre-existing diabetes mellitus and ARDS in critically ill patients with acute hypoxemic respiratory failure (AHRF). Methods: An ancillary analysis of a global, multi-centre prospective observational study (LUNG SAFE) was undertaken. LUNG SAFE evaluated all patients admitted to an intensive care unit (ICU) over a 4-week period, that required mechanical ventilation and met AHRF criteria. Patients who had their AHRF fully explained by cardiac failure were excluded. Important clinical characteristics were included in a stepwise selection approach (forward and backward selection combined with a significance level of 0.05) to identify a set of independent variables associated with having ARDS at any time, developing ARDS (defined as ARDS occurring after day 2 from meeting AHRF criteria) and with hospital mortality. Furthermore, propensity score analysis was undertaken to account for the differences in baseline characteristics between patients with and without diabetes mellitus, and the association between diabetes mellitus and outcomes of interest was assessed on matched samples. Results: Of the 4107 patients with AHRF included in this study, 3022 (73.6%) patients fulfilled ARDS criteria at admission or developed ARDS during their ICU stay. Diabetes mellitus was a pre-existing co-morbidity in 913 patients (22.2% of patients with AHRF). In multivariable analysis, there was no association between diabetes mellitus and having ARDS (OR 0.93 (0.78-1.11); p = 0.39), developing ARDS late (OR 0.79 (0.54-1.15); p = 0.22), or hospital mortality in patients with ARDS (1.15 (0.93-1.42); p = 0.19). In a matched sample of patients, there was no association between diabetes mellitus and outcomes of interest. Conclusions: In a large, global observational study of patients with AHRF, no association was found between diabetes mellitus and having ARDS, developing ARDS, or outcomes from ARDS. Trial registration: NCT02010073. Registered on 12 December 2013

Search for W′→tb→qqbbW' \rightarrow tb \rightarrow qqbb W ′ → t b → q q b b decays in pppp p p collisions at s\sqrt{s} s = 8 TeV with the ATLAS detector

A search for a massive W′ gauge boson decaying to a top quark and a bottom quark is performed with the ATLAS detector in pp collisions at the LHC. The dataset was taken at a centre-of-mass energy of s√=8 TeVs=8 TeV and corresponds to 20.3 fb −120.3 fb −1 of integrated luminosity. This analysis is done in the hadronic decay mode of the top quark, where novel jet substructure techniques are used to identify jets from high-momentum top quarks. This allows for a search for high-mass W′ bosons in the range 1.5–3.0 TeV TeV. bb-tagging is used to identify jets originating from bb-quarks. The data are consistent with Standard Model background-only expectations, and upper limits at 95 % confidence level are set on the W′→tbW′→tb cross section times branching ratio ranging from 0.16pb0.16pb to 0.33pb0.33pb for left-handed W′W′ bosons, and ranging from 0.10pb0.10pb to 0.21pb0.21pb for W′ bosons with purely right-handed couplings. Upper limits at 95 % confidence level are set on the W′-boson coupling to tb as a function of the W′ mass using an effective field theory approach, which is independent of details of particular models predicting a W′ boson

The use of gaming technology for rehabilitation in people with multiple sclerosis

Gaming technology – exergaming – is a novel tool to facilitate exercise, improve balance, and encourage rehabilitation training. This review will describe some of the key exergame research to promote physical activity and its use in rehabilitation in other diseases or clinical populations. We will then describe the current state of research in exergaming in people with multiple sclerosis and describe the theories for the mechanism behind some of the improvements in outcomes seen after using exergaming. Lastly, we will identify gaps in the literature and provide directions for future work in this growing area. The current work is contradictory and there is no consensus with regards to training duration/intensity and the outcomes used to assess the clinical effectiveness. This in part is due to the off-the-shelf nature of the games used. A more satisfactory approach would be the development of bespoke games which match a clinical need. Exergames are seen as enjoyable and could be effective in enhancing adherence to rehabilitation. However, the definitive RCT has yet to be carried out comparing exergaming to traditional exercise. </jats:p