Osteochondritis dissecans of the knee: Epidemiology, etiology, and natural history.

Osteochondritis dissecans of the knee is a disease that typically affects skeletally immature patients. Clinically manifested with knee pain, limping, and joint disfunction, this condition has remained misunderstood and undervalued for a long period. Although being a rare condition, its awareness is of utmost clinical interest because of the possible severe consequences it can bring when misrecognized or inadequately treated. Its etiology remains unclear and is still debated. Many theories have been proposed, including inflammation, local ischemia, subchondral ossification abnormalities, genetic factors, and repetitive mechanical microtrauma, with a likely interplay of the same. This review article aims to deliver and discuss current and up-to-date concepts on epidemiology, etiology, and natural history of this pediatric condition. Level of evidence: level V.

FIFA 11+ Kids: Challenges in implementing a prevention program.

Purpose: Soccer is a popular sport among children and adolescents that exposes to a high risk of injury. Several prevention programs, including the FIFA 11+ Kids program have been developed to decrease this injury rate. The aim of the study was to investigate the knowledge and use of the FIFA 11+ Kids program among soccer coaches of skeletally immature soccer players in a Swiss canton and analyze difficulties of implementing such a prevention program. Materials & methods: First, an online survey was sent to all soccer coaches involved in Swiss training programs for male players from 7 to 13 years of age. Coaches were identified through existing Swiss coaching networks. A total of 237 coaches completed the survey. Second, the FIFA 11+ Kids program was implemented in three soccer teams (players from 7 to 13 years of age) during 6 months in the same canton. Utilization of FIFA 11+ Kids program and compliance of coaches were recorded by the research staff. Results: Around 84% of the included coaches in the survey were certified. Of those, 59% had been taught injury prevention during their course(s). Only 14% of the included coaches knew one of the FIFA programs (11, 11+, 11+ Kids), of those, about one-third (10 out of 237) used the FIFA 11+ Kids program. After 6 months, none of the soccer coaches applied the entire FIFA 11+ Kids program twice a week. One coach had completely abandoned the program. The main reasons for their disapproval were the time and surveillance needed and the players' lack of motivation. They stated, however, that the exercises were good if used occasionally. Conclusion: Injury prevention should be integrated in every soccer coach education courses. An adaptation of the FIFA 11+ Kids program should be considered, especially for the youngest players.

[Specialized, global and interdisciplinary care for (young) sportswoman]. / Prise en charge spécialisée, globale et interdisciplinaire de la (jeune) femme sportive.

Women have made a place for themselves in sport, but there are still inequalities and specific characteristics compared to men. Puberty is marked by hormonal changes that give the female athlete advantages and disadvantages. She then goes through various periods of life that condition her relationship to her body and her performance. Anatomical and hormonal factors influence certain injuries. Proper management of the menstrual cycle can optimize performance. She is more at risk of nutritional deficiencies or energy deficit. Moreover, she suffers more from a negative body image, aggravated by the pressure of the perfect sportswoman! All of these aspects should be considered when taking care of her and following up regularly, in order to avoid long-term consequences.

La femme s'est fait une place dans le sport, mais il persiste des inégalités et certaines caractéristiques spécifiques par rapport à l'homme. La puberté est marquée par des modifications hormonales conférant à l'athlète féminine des avantages mais aussi des inconvénients. Elle traverse ensuite diverses périodes de vie qui conditionnent sa relation à son corps et ses performances. Des facteurs anatomiques et hormonaux influencent certaines blessures. Une gestion adaptée du cycle menstruel peut optimiser les performances. Elle est plus à risque de carences nutritionnelles ou de déficit énergétique. De plus, elle souffre davantage d'une image négative de son corps, aggravée par la pression de la femme sportive parfaite ! Tous ces aspects sont à considérer lors de sa prise en charge et de son suivi régulier, afin d'éviter des séquelles à long terme.

SafeSport: Perceptions of Harassment and Abuse From Elite Youth Athletes at the Winter Youth Olympic Games, Lausanne 2020.

OBJECTIVE: To analyze the Winter Youth Olympic Games (YOG) 2020 athletes' understanding and perceptions of harassment and abuse in sport and their knowledge of reporting mechanisms. DESIGN: A cohort study. SETTING: The Winter YOG2020 in Lausanne, Switzerland. PARTICIPANTS: Accredited athletes at the YOG2020. INTERVENTION: An athlete safeguarding educational program was delivered at the YOG2020. Participating athletes were encouraged to answer a survey embedded in the safeguarding educational materials during the YOG. MAIN OUTCOME MEASURES: Perception of occurrence of harassment and abuse as well as knowledge of the term "safe sport" and reporting mechanisms. RESULTS: The survey response rate of athletes attending the Safe Sport Booth was 69%. When asked to define Safe Sport, 10% of athletes at the YOG2020 correctly identified a sport environment free from harassment and abuse, 20% identified fair play/antidoping, and 19% safety. When presented with the definition of harassment and abuse, 30.4% expressed surprise, in contrast to 46% in the summer YOG2018. A third (32%) reported that harassment and abuse was either "likely" or "very likely" present in their sport, which was similar to the YOG2018 (34%). The group of athletes not knowing where to go to report harassment and abuse was greater than in the YOG2018 (26% vs 11%). There were no differences in responses between competitive sex (boys' vs girls' events) or type of sport (team vs individual). CONCLUSIONS: Outcomes of this study, such as the development of youth-friendly terminology and emphasizing mechanisms for reporting of harassment and abuse, should inform the development of safeguarding educational materials for youth athletes.

Geographical heterogeneity of doping-related knowledge, beliefs and attitude among 533 Youth Olympics participants.

OBJECTIVES: Doping-related knowledge, beliefs and attitude influence adolescent athletes' susceptibility to prohibited performance-enhancing substances. They might be modified by different cultural backgrounds. This study's aim was to analyse the geographical heterogeneity of doping-related knowledge, beliefs and attitude among adolescent elite athletes. DESIGN: Cross-sectional study. METHODS: A questionnaire was distributed to athletes participating in the Winter Youth Olympic Games 2020 in Switzerland. Main outcomes ('subjective and actual knowledge', 'beliefs' and 'attitude') were stratified for athletes' region of origin. Geographical heterogeneity was tested with a two-way analysis of variance, and two multiple regression analyses were conducted to assess independent associations of knowledge, age and athletes' geographical region with doping-related beliefs and attitude. RESULTS: 533 athletes (54% females, mean age: 16.0 ±â€¯1.0 years), completed the questionnaire (response rate: 33%). Actual knowledge was moderate-to-good (9.2 ±â€¯2.9 correct answers out of 13), and scores of attitude and beliefs showed favourable patterns. Considerable geographical heterogeneity was found for knowledge (p < 0.001), beliefs (p = 0.004) and attitude (p < 0.001). Higher subjective knowledge and actual knowledge were favourably associated with attitude (ß = -0.096, p = 0.049; ß = -0.316, p < 0.001) and beliefs (ß = 0.120, p = 0.016; ß = 0.212, p < 0.001), independent of age and geographical region. CONCLUSIONS: This study demonstrates considerable geographical heterogeneity of doping-related knowledge, beliefs and attitude, which are three essential target factors of doping prevention in adolescent elite athletes. This evidence should encourage medical doctors and other professionals to change their educative anti-doping approach from teaching knowledge about negative consequences into investigating and forming a young athlete's mind-set.

Sports injuries and illnesses at the Lausanne 2020 Youth Olympic Winter Games: a prospective study of 1783 athletes from 79 countries.

OBJECTIVE: To describe the injury and illness characteristics among participating athletes during the Lausanne 2020 Youth Olympic Winter Games (YOG 2020), 9-22 January 2020. METHODS: The daily number of athlete injuries and illnesses were recorded (1) through the reporting of all National Olympic Committee (NOC) medical teams and (2) in the polyclinic and medical venues by the Lausanne 2020 medical staff. RESULTS: In total, 1783 athletes from 79 NOCs were observed. NOC and Lausanne 2020 medical staff reported 228 injuries and 167 illnesses, equating 11.7 injuries and 8.6 illnesses per 100 athletes over the 14-day period. Injury incidence was highest for snowboard slopestyle (39%), bobsleigh (36%), snowboard big air (29%), ski slopestyle (29%), snowboard cross (24%) and ski cross (21%), and lowest for speed skating, snowboard halfpipe and curling (2%-4%). The highest incidence of illness was recorded for curling (21%), ski mountaineering (15%), snowboard halfpipe (13%), bobsleigh (11%), cross-country skiing (10%) and figure skating (10%). Almost one-third of injuries were expected to result in time loss and 17% of illnesses. Most injuries occurred to the knee (12%) and head (11%), and 64% of illnesses affected the respiratory system. Overall, women suffered more injuries and illness than males. CONCLUSION: Overall, injury and illness rates were similar compared with recent YOG. While the rate and characteristics of injury and illness varied between sports, consistent patterns across YOG are emerging. If addressed, changes in highlighted areas of risk could have a positive impact on the health and well-being of these young athletes.

Impact of early sports specialisation on paediatric ECG.

Athletes of pediatric age are growing in number. They are subject to a number of risks, among them sudden cardiac death (SCD). This study aimed to characterize the pediatric athlete population in Switzerland, to evaluate electrocardiographic findings based on the International Criteria for electrocardiography (ECG) Interpretation in Athletes, and to analyze the association between demographic data, sport type, and ECG changes. Retrospective, observational study of pediatric athletes (less than 18 years old) including medical history, physical examination, and a 12-lead resting ECG. The primary focus was on identification of normal, borderline, and abnormal ECG findings. The secondary observation was the relation between ECG and demographic, anthropometric, sport-related, and clinical data. The 891 athletes (mean 14.8 years, 35% girls) practiced 45 different sports on three different levels, representing all types of static and dynamic composition of the Classification of Sports by Mitchell. There were 75.4% of normal ECG findings, among them most commonly early repolarization, sinus bradycardia, and left ventricular hypertrophy; 4.3% had a borderline finding; 2.1% were abnormal and required further investigations, without SCD-related diagnosis. While the normal ECG findings were related to sex, age, and endurance sports, no such observation was found for borderline or abnormal criteria. Our results in an entirely pediatric population of athletes demonstrate that sex, age, and type of sports correlate with normal ECG findings. Abnormal ECG findings in pediatric athletes are rare. The International Criteria for ECG Interpretation in Athletes are appropriate for this age group.

The chromatin landscape of primary synovial sarcoma organoids is linked to specific epigenetic mechanisms and dependencies.

Synovial sarcoma (SyS) is an aggressive mesenchymal malignancy invariably associated with the chromosomal translocation t(X:18; p11:q11), which results in the in-frame fusion of the BAF complex gene SS18 to one of three SSX genes. Fusion of SS18 to SSX generates an aberrant transcriptional regulator, which, in permissive cells, drives tumor development by initiating major chromatin remodeling events that disrupt the balance between BAF-mediated gene activation and polycomb-dependent repression. Here, we developed SyS organoids and performed genome-wide epigenomic profiling of these models and mesenchymal precursors to define SyS-specific chromatin remodeling mechanisms and dependencies. We show that SS18-SSX induces broad BAF domains at its binding sites, which oppose polycomb repressor complex (PRC) 2 activity, while facilitating recruitment of a non-canonical (nc)PRC1 variant. Along with the uncoupling of polycomb complexes, we observed H3K27me3 eviction, H2AK119ub deposition and the establishment of de novo active regulatory elements that drive SyS identity. These alterations are completely reversible upon SS18-SSX depletion and are associated with vulnerability to USP7 loss, a core member of ncPRC1.1. Using the power of primary tumor organoids, our work helps define the mechanisms of epigenetic dysregulation on which SyS cells are dependent.

Morel-Lavallée Lesion of the Knee in the Young Athlete: About 2 Cases After Sports Trauma.

BACKGROUND: Differential diagnosis of soft tissue swelling on exposed body parts in the young athlete is large and mostly includes benign self-limiting conditions, once underlying lesion to the bone, the cartilage, and the ligaments is excluded. Morel-Lavallée lesion represents a rare soft tissue injury requiring prompt intervention to ensure favorable outcome. CASES: A 10-year-old boy presented with 2-week-old swelling of the medial side of the knee without recent traumatic event. Unawareness of Morel-Lavallée lesion in the differential diagnosis led to delayed diagnosis and treatment. A 16-year-old boy came to our pediatric tertiary care center with a similar presentation and history. Timely intervention allowed for favorable outcome and early return to play. CONCLUSIONS: Morel-Lavallée lesion is a rare entity in the pediatric population, although underreporting due to unfamiliarity with the diagnosis is highly probable. Raising awareness among professionals in charge of young athletes should allow for better reporting as well as for elaboration of a standardized treatment plan, including rapid intervention and early return to play.

[Health for performance†: a concept that must prevail in sports]. / Health for Performance†: un concept à ancrer dans le sport.

Competitive sports demand numerous sacrifices from young adolescent athletes to reach early performance. This comes at a high price: many injuries, sometimes serious, recurrent fatigue, or undue pressure, bordering on abuse definitions. We present a new concept, which seems quite obvious: health for performance. In the presence of complete biopsychosocial health, adolescent athletes can thrive and meet their athletic, social and academic goals. A conducive sports environment, one which integrates interdisciplinarity with healthcare stakeholders, can allow for a complete harmonious positive development, one which is aligned with Public Health goals. Healthy adolescents may become performing athletes, but they will most definitely contribute positively to their wellbeing, as well as society in general.

Le sport de compétition exige des jeunes adolescents de nombreux sacrifices pour la performance dès le plus jeune âge. Ceci n'est pas sans conséquences, comme en témoignent les blessures parfois graves, la fatigue fréquente et les pressions subies, proches des définitions de la maltraitance. Nous présentons ici un concept nouveau, pourtant si évident : la santé pour la performance. En présence d'une santé bio-psycho-sociale complète, les jeunes athlètes se développent harmonieusement et peuvent atteindre leurs objectifs. Un environnement sportif favorable, fonctionnant en interdisciplinarité avec les acteurs de la santé, permet un apprentissage physique complet et favorise un développement positif des adolescents, en accord avec les objectifs de santé publique. Ainsi ils contribueront tant à leur bien-être qu'à celui de la société.

[Adolescent sport medicine : do simple injuries really exist in youth athletes ?] / Médecine du sport chez les adolescents : qui a parlé de simples blessures ?

Offering an interdisciplinary approach to the athletic adolescent helps to expand the evaluation framework when investigating a medical complaint. It is important to use the opportunity of each consultation to take not only a detailed history of the sporting practice, but also to investigate the social and familial context as well as healthy lifestyle of the young athlete. Considering young athletes within the larger picture of their developmental context of adolescence offers an opportunity to better respect the psychological and physical needs of this life phase. These needs are strongly related to the promotion of a good health among young athletes.

L'approche interdisciplinaire de l'adolescent qui pratique du sport permet d'élargir le cadre d'évaluation lors de l'investigation d'une plainte médicale. Il est important de profiter de chaque opportunité de consultation pour faire non seulement une anamnèse détaillée de la pratique sportive, mais également du contexte social et familial ainsi que de l'hygiène de vie du jeune sportif. Replacer le jeune sportif dans le contexte développemental de l'adolescence offre une possibilité de mieux respecter les besoins fondamentaux psychiques et physiques liés à cette phase de vie, éléments qui sont fortement liés à la promotion d'une bonne santé.

[Adolescent and physical activity: addi(c)tive excesses]. / Adolescent et sportif: quand les excès s'addi (c) tionnent.

Benefits of physical activity during adolescence have widely been demonstrated. Yet, raising awareness among young athletes and their surrounding about risks associated with too early specialization or energy deficit--with or without eating disorder--is of outmost importance. Such behaviours can affect adolescents' physical or psychological development as well as compromise their athletic career not to mention the potential negative impact on their athletic performance. Primary care practitioners play an important role in early detection and prevention of overuse injuries as well as psychological distress associated with intense physical activity. Such situations need the intervention of an interdisciplinary team in order to prevent long-term complications.

[Sport medicine consultation for adolescents]. / Pédiatrie. (2.) Consultation de médecine du sport dédiée à l'adolescent.

Sport activity is a determinant of health and well-being for adolescents' psychological and physic development. Early detection of traumatic lesions or pathological condition among sportive adolescent in the light of their developmental stage is of outmost importance and is best done by an interdisciplinary team. This clinical management also aims at preventing consequences of inappropriate training. The CHUV has set-up a specific sports medicine outpatient consultation clinic for adolescents in the order to provide the best integrative management of young athletes.

PROX1 promotes metabolic adaptation and fuels outgrowth of Wnt(high) metastatic colon cancer cells.

The Wnt pathway is abnormally activated in the majority of colorectal cancers, and significant knowledge has been gained in understanding its role in tumor initiation. However, the mechanisms of metastatic outgrowth in colorectal cancer remain a major challenge. We report that autophagy-dependent metabolic adaptation and survival of metastatic colorectal cancer cells is regulated by the target of oncogenic Wnt signaling, homeobox transcription factor PROX1, expressed by a subpopulation of colon cancer progenitor/stem cells. We identify direct PROX1 target genes and show that repression of a pro-apoptotic member of the BCL2 family, BCL2L15, is important for survival of PROX1(+) cells under metabolic stress. PROX1 inactivation after the establishment of metastases prevented further growth of lesions. Furthermore, autophagy inhibition efficiently targeted metastatic PROX1(+) cells, suggesting a potential therapeutic approach. These data identify PROX1 as a key regulator of the transcriptional network contributing to metastases outgrowth in colorectal cancer.

The sphericity deviation score: a quantitative radiologic outcome measure of Legg-Calvé Perthes disease applicable at the stage of healing and at skeletal maturity.

AIM: This study aimed to determine if a new measure of sphericity of the femoral head, the Sphericity Deviation Score (SDS), could be estimated reliably at the stage of healing of Legg-Calvé-Perthes disease (LCPD) and to determine if the SDS at the healing stage reflects the outcome at skeletal maturity. METHODS: The SDS was measured with image analysis software on radiographs of 120 children with unilateral LCPD at healing of the disease and at skeletal maturity. The reproducibility of measurement was assessed. SDS values for hips in different Stulberg classes were calculated. On the basis of SDS values at healing of 82 children, a logistic regression model was developed to determine the probability of a good outcome at skeletal maturity. The validity of the model was tested on another 38 children. RESULTS: The SDS values at the stage of healing and at skeletal maturity were comparable. The SDS values were lowest for Stulberg Class I hips and highest for Class IV and V hips. The validated regression model showed a very high probability of a good outcome (Stulberg Class I or II) at skeletal maturity if the SDS at the stage of healing was below 10. CONCLUSIONS: A reliable estimate of the outcome of LCPD at skeletal maturity can be made by computing the SDS as soon as the disease heals.

[Targeted approach to osteoporosis for children and teenagers]. / Pédiatrie 5. Approche ciblée de l'ostéoporose chez l'enfant et l'adolescent.

The osteoporosis of the child and the teenager is a pathological reality; its multifactorial pathogenesis often requires a collaborative approach and multidisciplinary. The osteoporosis characterized by a reduction in the bone mineral density is not a uniform pathology; it must be dealt with on all the levels by analyzing the factors of risks, by giving itself the diagnostic means and while insisting on the importance of a preventive approach as well as therapeutic.

Lateral condyle fracture of the humerus in children treated with bioabsorbable materials.

The aim of this study was to compare clinical and radiological outcome of lateral condyle fracture of the elbow in children treated with bioabsorbable or metallic material. From January 2008 to December 2009, 16 children with similar fractures and ages were grouped according to the fixation material used. Children were seen at 3, 6, and 12 months and more than 4 years (mean 51.8 months) postoperatively. The clinical results were compared using the Mayo Elbow Performance Score (MEPS). Radiographic studies of the fractured and opposite elbow were assessed at last follow-up control. Twelve children had a sufficient followup and could be included in the study. Seven could be included in the traditional group and 5 in the bioabsorbable group. At 12 months, the MEPS was 100 for every child in both groups. Asymptomatic bony radiolucent visible tracks and heterotopic ossifications were noted in both groups. There were no significant differences in terms of clinical and radiological outcome between the two groups. The use of bioabsorbable pins or screws is a reasonable alternative to the traditional use of metallic materials for the treatment of lateral condyle fracture of the elbow in children.

Quantitative measures for evaluating the radiographic outcome of Legg-Calvé-Perthes disease.

BACKGROUND: Large sample sizes are needed if discrete outcome measures are used to perform outcome studies, whereas more practicable sample sizes are sufficient if continuous outcome measures are used. Recognizing the need to devise reliable continuous outcome measures for assessing the outcomes of treatment of Legg-Calvé-Perthes disease, we evaluated a method of quantifying the shape and size of the femoral head and the femoral-acetabular relationship from computer images of anteroposterior and lateral radiographs with the help of image-analysis software. METHODS: Radiographs of 121 skeletally mature individuals with healed Legg-Calvé-Perthes disease were analyzed, and the sphericity deviation score, femoral head enlargement, femoral neck growth inhibition, and composite femoral congruency arc were calculated. RESULTS: Each of these measurements was reproducible, with distinctly different values for hips in each of the Stulberg classes. Measures of sphericity and congruence (the sphericity deviation score and the composite femoral congruency arc) could very clearly discriminate between spherical and aspherical hips, and there was a strong correlation between these two measurements. CONCLUSIONS: The study shows that it is possible to have reliable quantitative measures of the outcome of Legg-Calvé-Perthes disease at skeletal maturity.