Injury Patterns in Highly Specialized Youth Athletes: A Comparison of 2 Pathways to Specialization.

CONTEXT: Sport specialization, commonly defined as intensive year-round training in a single sport to the exclusion of other sports, has been associated with an increased risk for overuse injury. Two pathways to becoming highly specialized are recognized: (1) having only ever played 1 sport (exclusive highly specialized) and (2) quitting other sports to focus on a single sport (evolved highly specialized). Understanding the differences in injury patterns between these groups of highly specialized athletes will inform the development of injury-prevention strategies. OBJECTIVE: To compare the distribution of injury types (acute, overuse, serious overuse) among evolved highly specialized athletes, exclusive highly specialized athletes, and low-moderately specialized athletes. DESIGN: Cross-sectional study. SETTING: Tertiary care pediatric sports medicine clinic between January 2015 and April 2019. PATIENTS OR OTHER PARTICIPANTS: A total of 1171 patients (age = 12.01-17.83 years, 59.8% female) who played ≥1 organized sports, presented with a sport-related injury, and completed a sports participation survey. MAIN OUTCOME MEASURE(S): Distribution of injury types (acute, overuse, serious overuse). RESULTS: The percentage of injuries due to overuse was similar between the exclusive and evolved highly specialized athletes (59.2% versus 53.9%; P = .28). Compared with low-moderately specialized athletes, exclusive and evolved highly specialized athletes had a higher percentage of overuse injuries (45.3% versus 59.2% and 53.9%, respectively; P = .001). Multivariate analysis of the highly specialized groups revealed sport type to be a significant predictor of a higher percentage of injuries due to overuse, with individual-sport athletes having increased odds of sustaining an overuse injury compared with team-sport athletes (odds ratio = 1.95; 95% CI = 1.17, 3.24). CONCLUSIONS: The distribution of injury types was similar between evolved and exclusive highly specialized youth athletes, with both groups having a higher percentage of injuries due to overuse compared with low-moderately specialized athletes. Among highly specialized athletes, playing an individual sport was associated with a higher proportion of overuse injuries compared with playing a team sport.

Knee, Low Back, and Shoulder Problems Among University and Professional Volleyball Players: Playing With Pain.

CONTEXT: The knee, low back, and shoulder account for most overuse injuries in volleyball. Previous researchers have used methodology that did not examine the extent of injury burden and effect on performance. OBJECTIVE: To develop a more accurate and complete understanding regarding the weekly prevalence and burden of knee, low back, and shoulder problems within the highest levels of men's volleyball, including the role that preseason complaints, match participation, player position, team, and age have on complaints. DESIGN: Descriptive epidemiology study. SETTING: Professional volleyball clubs and the National Collegiate Athletic Association Division I program. PATIENTS OR OTHER PARTICIPANTS: A total of 75 male volleyball players, representing 4 teams playing in their country's respective premier league (Japan, Qatar, Turkey, and the United States), participated over a 3-season period. MAIN OUTCOME MEASURE(S): Players completed a weekly questionnaire (Oslo Sports Trauma Research Centre Overuse Injury Questionnaire) reporting pain related to their sport and the extent to which knee, low back, and shoulder problems affected participation, training volume, and performance. Problems leading to moderate or severe reductions in training volume or performance or the inability to participate were considered substantial problems. RESULTS: The mean weekly prevalence of knee, low back, and shoulder problems based on 102 player-seasons was 31% (95% CI = 28%, 34%), 21% (95% CI = 18%, 23%), and 19% (95% CI = 18%, 21%), respectively. Most players (93%, 95/102 player-seasons) reported some level of knee (79%, n = 81/102 player-seasons), low back (71%, n = 72/102 player-seasons), or shoulder (67%, n = 68/102 player-seasons) complaints during the season. Most players (58%, n = 59/102 player-seasons) experienced at least 1 episode of substantial problems affecting the knee (33%, n = 34/102 player-seasons), low back (27%, n = 28/102 player-seasons), or shoulder (27%, n = 28/102 player-seasons). Players with preseason complaints had more in-season complaints than teammates without preseason problems (mean weekly prevalence: knee, 42% versus 8%, t49 = -18.726, P < .001; low back, 34% versus 6%, t32 = -12.025, P < .001; shoulder, 38% versus 8%, t30 = -10.650, P < .001). CONCLUSION: Nearly all included elite male volleyball players experienced knee, low back, or shoulder problems, and most had at least 1 bout that substantially reduced training participation or sport performance. These findings suggest that knee, low back, and shoulder problems result in greater injury burden than previously reported.

Focused extracorporeal shockwave therapy for youth sports-related apophyseal injuries: case series.

BACKGROUND: Apophyseal overuse injuries are self-limited with skeletal maturity; however, they may be a source of significant pain and time lost from training. There is a lack of consensus for its management with the current available treatment, which might lag behind the ongoing development of regenerative medicine. The current retrospective case study aimed to assess the potential effectiveness and short-term safety of extracorporeal shockwave therapy (ESWT) in apophyseal injuries. METHODS: Data from 22 growing athletes [15 patients with Osgood-Schlatter disease and seven patients with Sever's disease] who received ESWT at a sports medicine unit in a university hospital were reviewed. All patients received low energy (= 0.1 mJ/mm2) level-focused ESWT using electrohydraulic generation technology. The clinical focusing technique was used upon applying ESWT. RESULTS: The number of sessions received to achieve full recovery ranged from 1 to 3 sessions. The time from treatment initiation to previous activity level was 2 weeks in 14 patients (63.3%), 4 weeks in seven patients (31.8%) and 11 weeks in one patient (4.5%). No adverse events were reported. No recurrence occurred up to 3 months after the last session. CONCLUSION: ESWT is a potentially safe and effective treatment for apophyseal injuries. It may facilitate an early return to sport activities.

Unilateral transtibial prosthesis users load their intact limb more than their prosthetic limb during sit-to-stand, squatting, and lifting.

BACKGROUND: Lower limb prosthesis users exhibit high rates of joint pain and disease, such as osteoarthritis, in their intact limb. Overloading of their intact limb during daily activities may be a contributing factor. Limb loading biomechanics have been extensively studied during walking, but fewer investigations into limb loading during other functional movements exist. The purpose of this study was to characterize the lower limb loading of transtibial prosthesis users during three common daily tasks: sit-to-stand, squatting, and lifting. METHODS: Eight unilateral transtibial prosthesis users performed sit-to-stand (from three chair heights), squatting, and lifting a 10 kg box. Peak vertical ground reaction forces and peak knee flexion moments were computed for each limb (intact and prosthetic) to characterize limb loading and asymmetry. Ranges of motion of the intact and prosthetic ankles were also quantified. FINDINGS: Users had greater peak ground reaction forces and knee flexion moments in their intact limb for all tasks (p < 0.02). On average, the intact limb had 36-48% greater peak ground reaction forces and 168-343% greater peak knee flexion moments compared to the prosthetic limb. The prosthetic ankle provided <10° of ankle range of motion for all tasks, less than half the range of motion provided by the intact ankle. INTERPRETATION: Prosthesis users overloaded their intact limb during all tasks. This asymmetric loading may lead to an accumulation of damage to the intact limb joints, such as the knee, and may contribute to the development of osteoarthritis. Prosthetic design and rehabilitation interventions that promote more symmetric loading should be investigated for these tasks.

Tarsal Navicular Bone Stress Injuries: A Multicenter Case Series Investigating Clinical Presentation, Diagnostic Approach, Treatment, and Return to Sport in Adolescent Athletes.

BACKGROUND: Tarsal navicular bone stress injuries (BSIs) are considered "high risk" because of prolonged healing times and higher rates of nonunion in adult populations but, to our knowledge, have not been comprehensively examined in adolescent athletes. PURPOSE: To describe the characteristics of tarsal navicular BSIs in adolescents. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective analysis of patients aged 10 to 19 years with a radiographically diagnosed tarsal navicular BSI was performed at 8 academic centers over a 9-year study period. Age, sex, body mass index (BMI), primary sport, physical examination findings, imaging, treatment, surgical technique, return-to-sport time, and complications were analyzed. RESULTS: Among 110 patients (mean age, 14.7 ± 2.7 years; 65% female), common primary sports were cross-country/track and field (29/92 [32%]) and gymnastics/dance (25/92 [27%]). Grade 4 BSIs were identified in 44% (48/110) of patients, with fracture lines present on radiography or magnetic resonance imaging. Nonoperative treatment (mean age, 14.4 ± 2.6 years), consisting of protected weightbearing and either a protective boot (69/88 [78%]) or a cast (19/88 [22%]), was trialed in all patients and was successful in 94 patients (85%). Operative treatment (mean age, 17.1 ± 1.4 years) was ultimately pursued for 16 patients (15%). Patients who required surgery had a higher BMI and a higher percentage of fracture lines present on imaging (nonoperative: 36/94 [38%]; operative: 14/16 [88%]). The median time to return to weightbearing, running, and full sport was significantly longer in duration for the operative group than the nonoperative group (P <.05). Complications associated with surgery included 1 case each of delayed union, nonunion, and painful implants, the latter of which required secondary surgery. CONCLUSION: Adolescent tarsal navicular BSIs were identified most commonly in female patients in leanness sports. Adolescents who required surgery were more likely to be older, have higher BMIs, and have grade 4 BSIs, and they returned to sport within a median of 5 months after single- or double-screw fixation with a low risk of postoperative complications. A better understanding of the presenting signs and symptoms and appropriate diagnostic imaging of navicular BSIs may lead to an earlier diagnosis and improved outcomes.

Caregiver Awareness of Safe Pitching Recommendations in Youth Fastpitch Softball Pitchers.

Background: Although fastpitch softball participation continues to rise, there is a lack of established pitch count guidelines, potentially putting young female athletes at risk of overuse injuries. In addition to coaches, caregivers' ability to recognize and employ safe pitching guidelines plays an important role in athlete safety. Purpose/Hypothesis: The purpose of this study was to assess caregivers' knowledge of their child's pitching practices and their familiarity with softball pitching recommendations. We hypothesized that caregivers would be unaware of safe pitching recommendations in youth fastpitch softball. Study Design: Cross-sectional study. Methods: A 30-question survey was distributed to caregivers of youth fastpitch softball pitchers in age groups 10U (ie, ≤10 years), 12U, 14U, 16U, and 18U. The survey included questions on the demographic characteristics of caregivers and athletes, caregivers' knowledge of safe pitching recommendations, and athletes' pitching background and throwing habits. Comparisons of responses between the age groups were conducted using the chi-square test, Fisher exact test, or 1-way analysis of variance, as appropriate. Results: A total of 115 caregivers completed the survey. Of the respondents, 84% were between 31 and 50 years, and 81.7% had a degree beyond high school. Only 28.1% of caregivers reported participating in youth sports. When asked to estimate the number of pitches they considered a safe amount during a single outing, 28.7% of caregivers (n = 33) did not provide a limit, 4.3% (n = 5) stated no limit was needed, 32.2% (n = 37) suggested 25 to 80 pitches, 21.7% (n = 25) suggested 81 to 100 pitches, 12.2% (n = 14) suggested 100 to 150 pitches, and 0.9% (n = 1) suggested that >150 pitches were acceptable. These data emphasized that only 14.8% of the caregivers were aware of any pitching guidelines. However, 93% of caregivers acknowledged that they would adhere to recommendations if guidelines were made available. Conclusion: The study findings demonstrated that a majority of caregivers are unaware of current youth fastpitch softball pitching recommendations.

Ankle Active Range of Motion as an Essential Factor of Footwork Technique in the Prevention of Overuse Injuries in Flamenco Dancers / Rango de movimiento activo del tobillo como factor esencial de la técnica de zapateado en la prevención de lesiones por sobreuso en bailarinas de flamenco

Flamenco dance is a performing art which is based on footwork technique where the foot and ankle play an important role.The objective of this study was to investigate the effect of ankle active range of motion on external load and its efficacy as apredictor during a flamenco footwork technique, with consideration of accelerometer positions and dance proficiency. Twelveflamenco dancers composed of 6 professional and 6 amateurs participated voluntarily in this study for whom no significantdifferences were detected regarding age, mass or height. Participants completed a 15-second Zap-3 footwork test at a speedof 160 bpm (beats per minute), 180 bpm and as fast as they could. Triaxial accelerometers were positioned at the dominantankle, 5th lumbar vertebrae and 7th cervical vertebrae to calculate accumulated PlayerLoad and uniaxial PlayerLoad of the3 planes (anteroposterior, mediolateral and vertical) for each speed level. Percentage contributions were also calculated. Theeffect of dorsiflexion on the external load of the dominant ankle of both professional and amateur dancers existed only in theanteroposterior axis while dorsiflexion was related to the external load at the 7th cervical vertebrae and only amateurs wereaffected. Plantarflexion only affected the uniaxial contribution of the vertical-axis of professional dancers. These programswould be applied to develop a technique feedback system for the flamenco dancer to follow their own model with respectto the ideal. This would allow intervention in the prevention of overuse injuries in flamenco dance artists.(AU)

El baile flamenco es un arte en el que el zapateado tiene un papel muy relevante. El objetivo de este estudio fue investigar elefecto del rango de movimiento activo del tobillo sobre la carga externa y su eficacia como predictor durante la realizaciónde un zapateado flamenco, en función de las posiciones del acelerómetro y el dominio técnico de los participantes. Un totalde doce bailaoras de flamenco, 6 profesionales y 6 amateurs, participaron voluntariamente en este estudio y en los que nose encontraron diferencias significativas respecto a edad, peso o estatura. Los participantes realizaron un test de zapateadodenominado Zap-3 durante 15 segundos a una velocidad de 160 pulsos por minuto, 180 y tan rápido como pudieron. Secolocaron acelerómetros triaxiales en el tobillo del pie dominante, en la 5ª vértebra lumbar y en la 7ª vértebra cervical paracalcular la PlayerLoad acumulada y la PlayerLoad uniaxial de los 3 planos (anteroposterior, medio-lateral y vertical) en funciónde cada nivel de velocidad, así como sus contribuciones porcentuales. Solamente se ha encontrado relación entre la flexióndorsal del tobillo dominante y la carga externa en el eje anteroposterior, tanto en profesionales como amateurs, mientras quea nivel de la 7ª vértebra cervical sólo se ha encontrado relación entre la dorsiflexión y la carga externa en el grupo de amateurs.Respecto a la flexión plantar solo se ha encontrado relación a nivel uniaxial con el eje vertical de los bailarines profesionales.Estos programas podrían servir de ayuda a desarrollar un sistema de retroalimentación de la técnica para que el practicantede baile flamenco pueda seguir su propio modelo respecto al ideal. Esto permitiría intervenir en la prevención de las lesionespor sobreuso en los artistas de baile flamenco.(AU)

Imaging of Overuse Injuries of the Ankle and Foot in Sport and Work.

Overuse injuries of the ankle and foot are common injuries both in sport and in a work-related context. After clinical assessment, imaging is key for early diagnosis. In this overview article, we focus on imaging techniques, protocols, and imaging findings of overuse injuries of the ankle and foot; we emphasize the important role of structured reporting; and we discuss clinical symptoms, epidemiology, and risk factors in sports and in a work-related context.

Compliance compromises an interventional study on iron supplementation in female combatants.

INTRODUCTION: Low iron levels are related to overuse injuries, poor physical performance and cognitive impairments in female recruits. The aim of this study was to evaluate iron supplement compliance in female combatants during basic training, and its effect on haemoglobin (Hgb), ferritin and injuries. METHODS: 329 female recruits to light infantry units filled induction questionnaires regarding smoking status, previous overuse injuries and iron deficiency. Blood was drawn for Hgb and ferritin. Subjects with ferritin levels below 20 ng/mL were considered iron depleted and were prescribed a ferrous fumarate supplement. After 4 months of basic training, the subjects completed a follow-up questionnaire regarding overuse injuries, reasons for failure to complete basic training and compliance with iron supplementation. Blood tests were repeated. RESULTS: Mean ferritin levels declined during training (from 18.1±18.2 to 15.3±9.6, p=0.01). Compliance with iron supplementation was observed in 26 (26.3%) of the subjects. In compliant subjects, Hgb levels remained constant and ferritin levels increased by 2.9±5.4 (p=0.07). The main reasons for reported non-compliance were forgetfulness, 26 (35.6%), and gastrointestinal side effects, 17 (23.3%). Injuries during training were not found to be associated with iron status. Smokers had a significantly higher rate of reported injuries prior to training (p<0.01). CONCLUSIONS: Ferritin levels decline during training. Compliance with iron supplementation is low. Iron supplementation has a significant effect on ferritin levels, even in the non-compliance group. Injuries were not related to iron status in this group. Further research is needed in order to clarify the most appropriate iron supplementation method.

Pain and body position on the bicycle in competitive and recreational road cyclists: A retrospective study.

This study compared the presence of pain in recreational and competitive road cyclists and body position on the bicycle between cyclists with and without pain. Seventy-one cyclists completed a survey reporting existing cycling-related sites of pain and comfort. Static sagittal and frontal plane images were taken to analyse body position on the bicycle. Participants were separated into recreational and competitive road cycling groups, and further into cyclists reporting pain in the upper body, low back, buttocks/hips and knees for comparison with cyclists without pain. A logistic regression model investigated possible predictors of pain whilst cycling. Pain was present in 67% of recreational and 70% of competitive cyclists whilst comfort was reported by 81% of recreational and 75% of competitive cyclists. Trivial to moderate non-significant differences were observed for body position on the bicycle between cyclists with and without pain, and between cyclists with and without pain in the upper body, low back, buttocks/hips and knees. The predictive logistic model was not significant (p = 0.07) with a model fit predicted by McFadden R2 of 0.07. Given most cyclists reported both pain and comfort, comfort is probably not a good predictor of overuse injury risk.

Clinical characteristics of gradual onset injuries in recreational road cyclists - SAFER XXVII study over 5 years in 62758 race entrants.

OBJECTIVE: Gradual onset injuries (GOIs) in recreational cyclists are common but not well described. The aim of this study is to describe the clinical characteristics of GOIs (main anatomical regions, specific anatomical sites, specific GOIs, tissue type, severity of GOIs, and treatment modalities) of GOIs among entrants participating in a community-based mass participation-cycling event over 5 years. METHODS: During the 2016-2020 Cape Town Cycle Tour, 62,758 consenting race entrants completed an online pre-race medical screening questionnaire. 1879 reported GOIs in the previous 12 months. In this descriptive epidemiological study, we report frequency (% entrants) of GOIs by anatomical region/sites, specific GOI, tissue type, GOI severity, and treatment modalities used. RESULTS: The main anatomical regions affected by GOIs were lower limb (47.4%), upper limb (20.1%), hip/groin/pelvis (10.0%), and lower back (7.8%). Specifically, GOI were common in the knee (32.1%), shoulder (10.6%), lower back (7.8%) and the hip/buttock muscles (5.2%). The most common specific GOI was anterior knee pain (17.2%). 57.0% of GOIs were in soft tissue. Almost half (43.9%) of cyclists with a GOI reported symptom duration >12 months, and 40.3% of GOIs were severe enough to reduce/prevent cycling. Main treatment modalities used for GOIs were rest (45.9%), physiotherapy (43.0%), stretches (33.2%), and strength exercises (33.1%). CONCLUSION: In recreational cyclists, >50% of GOIs affect the knees, shoulders, hip/buttock muscles and lower back, and 40% are severe enough to reduce/prevent cycling. Almost 45% of cyclists with GOIs in the lower back; or hip/groin/pelvis; or lower limbs; or upper limb reported a symptom duration of >12 months. Risk factors associated with GOIs need to be determined and preventative programs for GOIs need to be designed, implemented, and evaluated.

Risk factors and injury prevention strategies for overuse injuries in adult climbers: a systematic review.

Introduction: Climbing is an increasingly popular activity and imposes specific physiological demands on the human body, which results in unique injury presentations. Of particular concern are overuse injuries (non-traumatic injuries). These injuries tend to present in the upper body and might be preventable with adequate knowledge of risk factors which could inform about injury prevention strategies. Research in this area has recently emerged but has yet to be synthesized comprehensively. Therefore, the aim of this study was to conduct a systematic review of the potential risk factors and injury prevention strategies for overuse injuries in adult climbers. Methods: This systematic review was conducted in accordance with the PRISMA guidelines. Databases were searched systematically, and articles were deemed eligible based upon specific criteria. Research included was original and peer-reviewed, involving climbers, and published in English, German or Czech. Outcomes included overuse injury, and at least one or more variable indicating potential risk factors or injury prevention strategies. The methodological quality of the included studies was assessed with the Downs and Black Quality Index. Data were extracted from included studies and reported descriptively for population, climbing sport type, study design, injury definition and incidence/prevalence, risk factors, and injury prevention strategies. Results: Out of 1,183 records, a total of 34 studies were included in the final analysis. Higher climbing intensity, bouldering, reduced grip/finger strength, use of a "crimp" grip, and previous injury were associated with an increased risk of overuse injury. Additionally, a strength training intervention prevented shoulder and elbow injuries. BMI/body weight, warm up/cool downs, stretching, taping and hydration were not associated with risk of overuse injury. The evidence for the risk factors of training volume, age/years of climbing experience, and sex was conflicting. Discussion: This review presents several risk factors which appear to increase the risk of overuse injury in climbers. Strength and conditioning, load management, and climbing technique could be targeted in injury prevention programs, to enhance the health and wellbeing of climbing athletes. Further research is required to investigate the conflicting findings reported across included studies, and to investigate the effectiveness of injury prevention programs. Systematic Review Registration: https://www.crd.york.ac.uk/, PROSPERO (CRD42023404031).

Sports-Related Shoulder Injuries Among Female Athletes.

PURPOSE OF REVIEW: The objectives of this review are to explore the recent literature evaluating sports-related shoulder injuries among female athletes. RECENT FINDINGS: Recent literature has highlighted sex-related differences in injury trends and patterns among athletes. Increased participation of women in both recreational and professional sports has resulted in increased exposure to injury. While men experience greater rates of shoulder injury overall, women tend to experience more overuse-related injuries. Evidence also suggests women are more susceptible to shoulder laxity and rotator cuff tears. In comparison to their male counterparts, women note poorer function, increased pain, and decreased activity level following shoulder injuries. Women may also be more likely to experience worse outcomes following surgical intervention. Sex-related differences in injury patterns and outcomes results from a combination of molecular and environmental influences, including hormone pathways, shoulder morphology, and differing rates of participation in, and athletic regulations among, certain sports. Sex-related differences occur in how athletes sustain, experience, and recover from sports-related injuries. A comprehensive understanding of sex-related injuries enhances clinical decision making, treatment, and recovery. Further research is needed to clarify sex as an independent variable when evaluating sports-related shoulder injuries.

Association of Training and Game Loads to Injury Risk in Junior Male Elite Ice Hockey Players: A Prospective Cohort Study.

Background: Training and game loads are potential risk factors of injury in junior elite ice hockey, but the association of training and game loads to injuries is unknown. Purpose: To investigate the association of chronic training and game loads to injury risk in junior male elite ice hockey players. Study Design: Cohort study; Level of evidence, 2. Methods: In this prospective cohort study, we monitored all health problems among 159 male junior ice hockey players (mean age, 16 years; range, 15-19 years) at sports-specific high schools during the 2018-2019 school year. Players reported their health problems every week using the Oslo Sports Trauma Research Center Overuse Questionnaire on Health Problems (OSTRC-H2). The number of training sessions and games was reported for 33 weeks. We calculated the previous 2-week difference in training/game loads as well as the cumulative training/game loads of the previous 2, 3, 4, and 6 weeks and explored potential associations between training/game loads and injury risk using mixed-effects logistic regression. Results: The players reported 133 acute injuries, 75 overuse injuries, and 162 illnesses in total, and an average of 8.8 (SD ±3.9) training sessions and 0.9 (SD ± 1.1) games per week. We found no association between the difference of the two previous weeks or the previous 2- 3- and 4-week cumulative, training or game load and acute injuries, nor the difference of the two previous weeks, or the previous 4- and 6-week cumulative, training or game load and overuse injuries (OR, ∼1.0; P > .05 in all models). Conclusion: In the current study of junior elite ice hockey players, there was no evidence of an association between cumulative exposure to training/game loads and injury risk.

Prevalence of sport specialisation and association with injury history in youth football.

OBJECTIVES: The aims of this study were to determine the prevalence of sport specialisation in youth football, and to investigate the associations of sport specialisation and volume of sport participation with injury history. DESIGN: Cross-sectional questionnaire. SETTING: New Zealand youth football teams. PARTICIPANTS: 414 youth football players aged 10-15 years. MAIN OUTCOME MEASURES: The level of specialisation, average weekly sport participation and free-play volume were recorded. 12-month injury history was captured and grouped by injury type. Associations between level of specialisation and demographic variables were analysed using chi square tests. Logistic regression was used to investigate associations between injury history, level of specialisation, and volume of participation. RESULTS: Participants were classified as high (43%), moderate (38%), or low (19%) specialised (n = 399 complete). High specialisation was more likely in boys, older participants, and those from large schools. Highly specialised participants were more likely to report a history of gradual onset injury than those who were low specialised (n = 340 with complete injury data). Odds of reporting a gradual onset injury also increased with greater weekly and annual sport participation volume. CONCLUSIONS: There is a high prevalence of sport specialisation in youth football, and it is associated with increased incidence of gradual onset injury.

The Most Common Handball Injuries: A Systematic Review.

Handball is a team sport involving a great physical demand from its practitioners in which a high number of injuries occur, affecting individual and collective performance. Knowledge of the injuries is of great importance for their prevention. The objective of the present study was to identify, locate and compare the most frequent injuries and injury mechanisms in handball practice. It was carried out following the Preferred Informed Item for Systematic Reviews and Meta-analysis (PRISMA) guidelines. The source of data collection was direct consultation of the PubMed and Medline databases. Several keywords were used for the documentary retrieval, and the quality of the studies that were selected was evaluated. Of the 707 studies retrieved, only 27 were considered appropriate for the review, and quality scores were obtained that ranged from 10 to 26 points, out of a maximum of 28. The most frequent injuries in handball players are located in the lower limbs (thigh, knee and ankle), and in the shoulder in the upper limbs. Regarding the playing position, the players who play over the 6-m line are the most affected by injuries, while the women players have a higher probability of injury. Most injuries occur during competition.

Machine-learned-based prediction of lower extremity overuse injuries using pressure plates.

Although running has many benefits for both the physical and mental health, it also involves the risk of injuries which results in negative physical, psychological and economical consequences. Those injuries are often linked to specific running biomechanical parameters such as the pressure pattern of the foot while running, and they could potentially be indicative for future injuries. Previous studies focus solely on some specific type of running injury and are often only applicable to a gender or running-experience specific population. The purpose of this study is, for both male and female, first-year students, (i) to predict the development of a lower extremity overuse injury in the next 6 months based on foot pressure measurements from a pressure plate and (ii) to identify the predictive loading features. For the first objective, we developed a machine learning pipeline that analyzes foot pressure measurements and predicts whether a lower extremity overuse injury is likely to occur with an AUC of 0.639 and a Brier score of 0.201. For the second objective, we found that the higher pressures exerted on the forefoot are the most predictive for lower extremity overuse injuries and that foot areas from both the lateral and the medial side are needed. Furthermore, there are two kinds of predictive features: the angle of the FFT coefficients and the coefficients of the autoregressive AR process. However, these features are not interpretable in terms of the running biomechanics, limiting its practical use for injury prevention.

Risk factors and prevention strategies for shoulder injuries in overhead sports: an updated systematic review.

PURPOSE: The aim of this systematic review was to update the knowledge on risk factors and prevention strategies for shoulder injuries in overhead sports with special emphasis on methodological quality. METHODS: All methodological procedures were performed in line with a previous systematic review by Asker et al. (2018). The literature search was conducted in the PubMed, Google Scholar, Cochrane, and SPORT-Discuss databases. Due to the risk of bias assessment, only studies with at least an acceptable methodological quality were included. A best-evidence synthesis was performed to clarify the evidence and direction of the risk factors and prevention strategies. RESULTS: A total of nine studies were included in the data extraction process. One study had a high and eight studies had an acceptable methodological quality. Seven cohort studies investigated risk factors and two randomised controlled trails evaluated prevention strategies. Moderate evidence was found for two non-modifiable (playing position, gender) and three modifiable factors (shoulder rotational strength, scapular dyskinesia, shoulder prevention programme) that were associated with the shoulder injury risk. All further risk factors had moderate and no association with risk (shoulder rotational ROM, joint position sense) or limited (history of shoulder/elbow pain, age, training experience, training volume, school grade, playing level), and conflicting evidence (setting). CONCLUSIONS: There is moderate evidence for two non-modifiable (playing position, gender) and three modifiable factors (shoulder rotational strength, scapular dyskinesia, shoulder prevention programme) being associated with the shoulder injury risk in overhead sports.

The Prevalence of Shoulder Disorders among Professional Bullfighters: A Cross-Sectional Ultrasonography Study.

We aimed to investigate clinical and ultrasound signs of shoulder overuse injuries in professional bullfighters; side-to-side differences (dominant vs. non-dominant); and to determine potential differences according to bullfighters' categories. An observational cross-sectional study was conducted. Thirty professional and active bullfighters were assessed. A bilateral ultrasound assessment of the subacromial bursa, long biceps head tendon (LHBT), and rotator cuff was performed to determine the presence of bursitis, subluxation, partial or total tendon rupture, tenosynovitis, or calcification. Supraspinatus tendon thickness was measured. Finally, a battery of clinical orthopedic tests (Yergason, Jobe, infraspinatus, Gerber, and bursa tests) were also performed. Most identified ultrasound findings were located in the dominant side, being the presence of bursitis (n = 9; 30%), LHBT tenosynovitis (n = 8; 26.7%), and subscapularis tendon calcification (n = 5; 16.7%) the most prevalent. No side-to-side or between-categories differences were found for supraspinatus tendon thickness (all, p > 0.05). The most frequent positive signs were the infraspinatus test (40.0%), Gerber lift-off test (33.3%), and bursitis, Jobe, and Yergason tests (all, 26.7%). Ultrasound signs were commonly found at LHBT, subacromial bursa, and rotator cuff in professional bullfighters without difference between categories and sides. No side-to-side or between-categories differences were found. Positive clinical test signs suggestive of bursitis, LHBT, and rotator cuff tendinopathy were frequently observed.