The etiology of osteochondritis dissecans is hypothesized as repetitive microtrauma, resulting in an interruption of blood supply. Due to the location of the most common lesions on the medial femoral condyle, impingement of either the medial tibial spine or inferior pole of the patella against the adjacent medial femur may be responsible. It is much more common in athletic males than other groups. This article reviews the current treatment options for lesions around the knee.
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Simon M. Thompson, Mary Jones, Jonathon R. Lavelle, and Andy Williams
Alun Williams, Lucy Whitman, Yve Le Page, Colin Le Page, Graham Chester, and Simon J. Sebire
Non-Eleri Thomas, Stephen-Mark Cooper, Simon P. Williams, Julien S. Baker, and Bruce Davies
The purpose of this study was to examine relationships between aerobic fitness (AF), fatness, and coronary-heart-disease (CHD) risk factors in 12- to 13-year-olds. The data were obtained from 208 schoolchildren (100 boys; 108 girls) ages 12.9 ± 0.3 years. Measurements included AF, indices of obesity, blood pressure, blood lipids and lipoproteins, fibrinogen, homocysteine, and C-reactive protein. An inverse relationship was found between AF and fatness (p < .05). Fatness was related to a greater number of CHD risk factors than fitness was (p < .05). Further analysis revealed fatness to be an independent predictor of triglyceride and blood-pressure levels (p < .05). Our findings indicate that, for young people, fatness rather than fitness is independently related to CHD risk factors.
Sean Williams, Grant Trewartha, Matthew J. Cross, Simon P.T. Kemp, and Keith A. Stokes
Purpose:
Numerous derivative measures can be calculated from the simple session rating of perceived exertion (sRPE), a tool for monitoring training loads (eg, acute:chronic workload and cumulative loads). The challenge from a practitioner’s perspective is to decide which measures to calculate and monitor in athletes for injury-prevention purposes. The aim of the current study was to outline a systematic process of data reduction and variable selection for such training-load measures.
Methods:
Training loads were collected from 173 professional rugby union players during the 2013–14 English Premiership season, using the sRPE method, with injuries reported via an established surveillance system. Ten derivative measures of sRPE training load were identified from existing literature and subjected to principal-component analysis. A representative measure from each component was selected by identifying the variable that explained the largest amount of variance in injury risk from univariate generalized linear mixed-effects models.
Results:
Three principal components were extracted, explaining 57%, 24%, and 9% of the variance. The training-load measures that were highly loaded on component 1 represented measures of the cumulative load placed on players, component 2 was associated with measures of changes in load, and component 3 represented a measure of acute load. Four-week cumulative load, acute:chronic workload, and daily training load were selected as the representative measures for each component.
Conclusions:
The process outlined in the current study enables practitioners to monitor the most parsimonious set of variables while still retaining the variation and distinct aspects of “load” in the data.
Matthew J. Cross, Sean Williams, Grant Trewartha, Simon P.T. Kemp, and Keith A. Stokes
Purpose:
To explore the association between in-season training-load (TL) measures and injury risk in professional rugby union players.
Methods:
This was a 1-season prospective cohort study of 173 professional rugby union players from 4 English Premiership teams. TL (duration × session-RPE) and time-loss injuries were recorded for all players for all pitch- and gym-based sessions. Generalized estimating equations were used to model the association between in-season TL measures and injury in the subsequent week.
Results:
Injury risk increased linearly with 1-wk loads and week-to-week changes in loads, with a 2-SD increase in these variables (1245 AU and 1069 AU, respectively) associated with odds ratios of 1.68 (95% CI 1.05–2.68) and 1.58 (95% CI 0.98–2.54). When compared with the reference group (<3684 AU), a significant nonlinear effect was evident for 4-wk cumulative loads, with a likely beneficial reduction in injury risk associated with intermediate loads of 5932–8651 AU (OR 0.55, 95% CI 0.22–1.38) (this range equates to around 4 wk of average in-season TL) and a likely harmful effect evident for higher loads of >8651 AU (OR 1.39, 95% CI 0.98–1.98).
Conclusions:
Players had an increased risk of injury if they had high 1-wk cumulative loads (1245 AU) or large week-to-week changes in TL (1069 AU). In addition, a U-shaped relationship was observed for 4-wk cumulative loads, with an apparent increase in risk associated with higher loads (>8651 AU). These measures should therefore be monitored to inform injury-risk-reduction strategies.
Richard Tyler, Marianne Mannello, Rebecca Mattingley, Chris Roberts, Robert Sage, Suzan R Taylor, Malcolm Ward, Simon Williams, and Gareth Stratton
Background:
This is the second Active Healthy Kids Wales Report Card. The 2016 version consolidates and translates research related to physical activity (PA) among children and youth in Wales, and aims to raise the awareness of children’s engagement in PA and sedentary behaviors.
Methods:
Ten PA indicators were graded using the Active Healthy Kids—Canada Report Card methodology involving a synthesis and expert consensus of the best available evidence.
Results:
Grades were assigned as follows: Overall PA, D+; Organized Sport Participation, C; Active and Outdoor Play, C; Active Transportation, C; Sedentary Behaviors, D-; Physical Literacy, INC; Family and Peer Influences, D+; School, B; Community and the Built Environment, C; and National Government Policy, Strategies, and Investments, B-.
Conclusions:
Despite the existence of sound policies, programs, and infrastructure, PA levels of children and youth in Wales are one of the lowest and sedentary behavior one of the highest globally. From the 2014 Report Card, the Family and Peer Influences grade improved from D to D+, whereas Community and the Built Environment dropped from B to C. These results indicate that a concerted effort is required to increase PA and decrease sedentary time in children and young people in Wales.
