bluuebunny/crossref_metadata_2025_split huggingface dataset:
A simple clinical screening test can identify elite female football players with increased knee valgus angles
Authors: Nilstad A , Kristianslund E , Krosshaug T , Steffen K , Myklebust G , Bahr R , Andersen T E 
Published: March 2011

BackgroundA link has been suggested between increased dynamic knee valgus and the risk of anterior cruciate ligament (ACL) injuries in female athletes. However, these findings are based on complex time-consuming 3D motion analysis. There is a need for simple screening tools to identify athletes at increased risk of an ACL rupture.ObjectiveTo assess whether an experienced clinician can identify athletes with increased valgus angles and moments during a vertical drop jump using a simple screening test.DesignCross-sectional study.ParticipantsElite female football players.MethodsPlayers in the Norwegian elite league (12 teams) were screened for potential risk factors for ACL injuries. Knee kinematics and kinetics in the landing phase of a 30 cm vertical drop jump were calculated using 3D motion analysis. Using a similar jump task, a physiotherapist assessed how well players stabilised their knees, and scored their knee control as ‘good’, ‘reduced’ or ‘poor’.ResultsOf the 136 players included, 38% were classified as ‘good’, 34% had ‘reduced’ control and 28% were scored as ‘poor’. Players with good control had significantly lower maximal valgus angles compared to players with poor control (0.5° vs 6.8°, p≤0.001). There were no differences in valgus moments (0.28 Nm/kg vs 0.28 Nm/kg, p=1.0). One-fifth of all players (17.6%) displayed valgus angles more than one SD above the mean in the 3D analyses (3.1° ±4.5°). The screening test captured 87.5% of these players. 22 (16.2%) players were classified in the ‘poor’ group without displaying high valgus angles.ConclusionThe screening test identified 87.5% of players with increased valgus angles. No correlation was found between valgus angles and moments, and the test could not identify players with high valgus moments. Further investigations are needed to determine the cut-off value for defining high- versus low-risk groups, as well as the predictive value of the test.
What is more dangerous – football, skiing or snowboarding?
Authors: Flørenes T , Bjørneboe J , Andersen T E , Heir S , Bahr R 
Published: March 2011

BackgroundIt is well known that professional football has a high injury risk. The FIS Injury Surveillance System increases our knowledge of injuries to elite skiers and snowboarders. But what is more dangerous?ObjectiveTo compare the injury risk in World Cup (WC) skiing and snowboarding with Norwegian professional football (Tippeligaen).Design/SettingWe conducted season-ending interviews with athletes from selected WC-teams in alpine skiing, freestyle skiing and snowboarding during the 2006–2007 and 2007–2008 winter seasons on acute injuries sustained (November through mid-March). Injury information was prospectively collected from medical staff in all Tippeliga-teams (n=16) and extracted from mid-March through July for the 2007 and 2008 seasons to best imitate the skiing/snowboarding season. Injury rate was calculated as number of injuries per 100 athletes per season.ResultsAmong 521 alpine, 416 freestyle and 421 snowboard athletes we registered 155, 115 and 159 time-loss injuries, corresponding to 29.8 (95% CI 25.1 to 34.4), 27.6 (22.6–32.7) and 37.8 (31.9–43.6) injuries per 100 athletes per season. In Tippeligaen, 308 time-loss injuries were recorded among 440 players, corresponding to 70.0 (62.2–77.8) injuries per 100 players (RR: 2.4 (1.9–2.9) vs alpine, 2.5 (2.0–3.2) vs freestyle and 1.9 (1.5–2.2) vs snowboard). The rate of severe injuries (absence >28 days) was 11.3 (8.4–14.2), 13.8 (10.2–17.3), and 14.4 (10.8–18.1) injuries per 100 alpine, snowboard and freestyle athletes per season and 9.3 (6.5–12.2) in football. The rate of severe injuries was higher in freestyle skiing compared to football (RR: 1.5, 1.0–2.3) while no difference was found between football and alpine skiing (RR: 0.8, 0.6–1.2) or snowboarding (RR: 0.7, 0.5–1.0).ConclusionThe injury risk among WC skiers and snowboarders is high, but only half of that in elite Norwegian football. However, the risk for severe injuries is the same in alpine skiing and snowboarding as in football, and even higher in freestyle skiing.
Pre-season screening of core muscle balance and control tests in the lumbar spine in professional road cyclists can we prevent uncontrolled movement?
Authors: Hadala M , de Bernardo N , Vera P , Laíz C , Barrios C 
Published: March 2011

BackgroundAsymptomatic musculoskeletal function, normal range of joint motion and normal muscle strength are considered not adequate star points to design a prevention injury program.ObjectiveTo assess core muscle balance and control in the lumbar spine using simple functional tests during low load activity and high load dynamic movements.DesignCross-sectional descriptive study.SettingProfessional road cyclists.Patients51 elite road cyclists were functionally evaluated at the beginning of the 2010 season. All injuries affecting racers during previous seasons were recorded throughout a clinical oriented interview.InterventionsSpecific assessment of the site (lower back and pelvis) and direction of uncontrolled movement, under low and high loading within functionally orientated tasks.Main outcome measurementsThree tests were conducted in the crook laying position: (1) double leg lift and lower, (2) single leg extension, (3) bridge+single leg extension. In two first tests the ‘stabilizer’ pressure biofeedback unit was used to measure the influence of the global muscle system on trunk stability. Muscle functional extensibility of iliopsoas, tensor fasciae late, anterior rectus femoris and hamstrings were also evaluated.ResultsUncontrolled movements in lower back in low load test were found in flexion (57% of cyclist) and extension test (67%). Passive and active restriction of hamstrings while sitting showed significant correlation with impaired low back movements in flexion test (p<0.05). Weakness of the gluteus maximus correlated with uncontrolled movement in low back extension at high loading. Impaired movements in pelvic girdle (70%) showed a statistically significant relationship with asymmetrical passive restriction of rectus anterior muscle (p<0.03).ConclusionMuscle imbalance between hamstrings and hip flexors together with weak hip extensors provoke uncontrolled movements in the low back of cyclists, predisposing them to more overuse injuries. A specific preventive program should be desirable.
Longitudinal study of dynamic lower limb alignment during landing in pubescent children
Authors: Kimura Y , Ishibashi Y , Tsuda E , Yamamoto Y , Maeda S , Hayashi Y , Sasaki S 
Published: March 2011

BackgroundFemale athletes have increased risk of anterior cruciate ligament (ACL) injury after puberty. It has been demonstrated that female athletes have greater valgus lower limb alignment than males during landing, and this may contribute to the gender disparity in ACL injury risks. In early teens, however, the gender difference in lower limb alignment has not been elucidated.ObjectiveThe purpose of this study was to examine whether dynamic lower limb alignment alters during the pubertal stage in girls and boys, in a longitudinal survey.DesignCohort study.SettingsElementary school students with no lower extremity complaints.Participants33 females and 27 males aged 10 to 11 years old were evaluated and followed for three consecutive years.Assessment of risk factorThe subjects performed a drop-vertical-jump by dropping directly down off a box, and immediately performing a maximum vertical jump. The frontal view of the lower limb was recorded with a digital video camera and the images at deepest point of body (landing) were captured.Main outcome measurementThe separate distances between right and left hips and knees were measured. The knee separation distances normalised by the hip separation distance (K/H ratio) were used as a parameter representing the valgus/varus lower limb alignment.ResultsAt landing, K/H ratio in females was 0.41±0.10 in the first year, 0.39±0.11 in the second year, 0.36±0.10 in the third year. In males, the ratios were 0.60±0.21, 0.52±0.17, 0.55±0.19. Knee valgus alignment in females increased with maturation, with significant difference between first year and third year. However, there were no significant changes in males.ConclusionDifferent changing pattern of lower limb alignment during landing was seen between boys and girls, and it may be related to the gender difference in incidence of ACL injury.
Musculoskeletal pain in recreational runners prior to race participation: a cross-sectional survey in 1049 runners
Authors: Lopes A D , Saragiotto B T , Yamato T P , Adami F , Costa L O P 
Published: March 2011

BackgroundWe know that high-performance sports place high stress in the musculoskeletal system, often resulting in injury, pain, or other complaints. It is not unusual for athletes to decide to participate in important competitions, despite an ongoing disability or injury. However, we are unaware of any study that has presented any clear information about this issue in recreational runners.ObjectiveThe aims of this study were to calculate the prevalence of presence of musculoskeletal pain in amateur runners immediately before a race and to identify possible factors that could be associated with presence of musculoskeletal pain in this population.DesignThis is a cross-sectional survey study.SettingThese runners were recreational athletes that participated in different races in São Paulo (Brazil), the distance of these races ranged from 5.000/10.000 meters.ParticipantsA convenience sample of 1049 runners, 24.1% women (n=253) and 75.9% men (n=796).Assessment of risk factorsThis questionnaire contained information on presence of musculoskeletal pain, demographic characteristics, weight, body mass index, running experience, running mileage/week, number of training sessions/week, predominant training surface and coaching utilisation. We used logistic regression analysis to indentify associations between possible factors and presence of musculoskeletal pain (p<0.05). The data were collected 1–2 h prior to the races.Main outcome measurementsPresence of musculoskeletal pain.ResultsThe prevalence of presence of musculoskeletal pain was 20% and 26.9% for men and women respectively. Running experience (OR=2.97, 95% CI 1.59 to 5.56) and weekly running distance (OR=1.88, 95% CI 1.02 to 3.48) were associated with presence of musculoskeletal pain in men prior to the race.ConclusionThe prevalence of presence of musculoskeletal pain in amateur runners prior to the race was high. We have observed higher experience in running (ie, more than 10 years) and high training volumes (ie, more than 50 Km/week) were associated with presence of musculoskeletal pain.
Influence of a preventive training program on the lower limbs kinematics and vertical jump height of male volleyball athletes
Authors: Leporace G , Metsavaht L , Praxedes J , Pereira G , Pinto S , Chagas D , Chame F , Batista L A 
Published: March 2011

BackgroundThe effectiveness of preventive training programs (PTP) aiming at changing the biomechanical behaviour related to anterior cruciate ligament injuries is subject to pre-existing risk. However, these assumptions are based on studies in females. Moreover, it is unclear what influence this training has on performance of young male athletes.ObjectiveTo examine the influence of a PTP on changes in kinematics during landings and in maximum vertical jump height (VJH) in males.Design6 weeks prospective exercise intervention.SettingYoung male volleyball athletes.Participants15 male volleyball athletes (13±0.7 years, 1.70±0.12 m, 60±12 kg).InterventionsPTP consisting of plyometric, balance and core stability exercises three times per week for 6 weeks. Bilateral vertical jumps with double leg (DL) and single leg (SL) landings were performed to measure the effects of training.Main outcome measurementsKinematics of knee and hip before and after training and VJH attained during both tasks after training. The hypothesis was that the PTP would produce improvements in VJH, but would not generate great changes in biomechanical behaviour.ResultsThe only change revealed for the SL was the longest duration of landing (p=0.0273), while in the DL was the largest angular displacement of the knee (p=0.0371). The training did not significantly alter the VJH in the SL (diff: 2.7 cm, p=0.3054) or DL condition (diff: 3.5 cm, p=0.3635).ConclusionDespite the alterations in the kinematics behaviour, the changes observed are specific for each landing task, which highlights the importance of the principle of specificity. Despite the absence of significant increases in the VJH after training, the absolute differences pre to post training showed an increase consistent with other studies that compared the results with control groups. The present study showed that short time PTP in low-risk populations, although generating little influence on the kinematics, are capable of enhancing performance.
Protocol for the dano-run study: a 1-year observational follow up study on running related injuries in 1000 novice runners
Authors: Nielsen R , Ramskov D , Sorensen H , Lind M , Rasmussen S , Buist I 
Published: March 2011

BackgroundThe knowledge on the relation between running patterns and Running Related Injuries (RRIs) is sparse. Studies have tried to document a relationship. However, no firm conclusions can be made. Still it is necessary to identify which running exposures increase the risk of injuries and which exposures might be considered safe.ObjectiveThe purpose of this study is to investigate the link between the running volume and the development of RRIs.DesignObservational prospective follow up study.SettingClinical setting on novice and recreational athletes.ParticipantsHealthy individuals (N=1000) who have not been running the past 1 year is included. All participants receive a global positioning system (GPS) watch (Garmin FR 110) and a pair of neutral running shoes (Adidas Glide 2). They are instructed to start running as much as they want, two times a week as a minimum. They must wear their GPS watch at each training session and upload data to an internet based database. All participants are followed for 1 year.Assessment of risk factorsRunning volume measured as absolute number of kilometres and the graduation in kilometres pr. week over a period of 3 weeks.Main outcome measurementRRI is defined as any musculoskeletal complaint of the lower extremity or back causing a restriction of running for at least 1 week.ResultsTime to RRI is compared between groups with different absolute running volumes. In a similar way time to injury is compared between individuals with different weekly training graduations.ConclusionThis study may be the first study to adequately measure running patterns reliably in a large sample. The exposure is quantified by GPS, which is not affected by subject recall and is therefore a clear methodological improvement compared to previous studies. If absolute volume or running graduation over time seems to lead to injury, the study findings and methodology create a solid foundation for future randomised controlled trials in this field.
‘At risk’ positioning and hip biomechanics of the peewee ice hockey sprint start
Authors: Philippon M J , Stull J D , LaPrade R F 
Published: March 2011

Background‘At risk’ motion of the hip is defined primarily by internal rotation during flexion, reportedly increasing vulnerability to labral injury and observed during the recovery phase of the adult ice hockey skating stride. No biomechanical analysis has focused on ‘at risk’ hip motion in youth hockey players sprint starts.ObjectiveTo investigate the biomechanics of the male youth ice hockey sprint start with attention to the hip and a previously identified ‘at risk’ position. We hypothesised that youth hockey players display ‘at risk’ hip motion during the sprint start.DesignDescriptive in vivo laboratory study.SettingThe study was conducted in a biomechanics laboratory on 6.4 mm acrylic surface manufactured specifically for ice hockey skate testing.Participants12 healthy male Peewee ice hockey players (mean age: 10.8 (± 0.6 years)).Assessment of risk factorsParticipants were assessed for hip flexion at maximum internal rotation by 10 high-speed infrared cameras that recorded 35 anatomical identifiers to assess the 3-D biomechanics of the ice hockey sprint start over 100 time-segments comprising the sprint stride.Main outcome measurementsData was collected for hip flexion, extension, abduction, adduction, external and internal rotation.ResultsDuring the recovery phase of the sprint start, maximum internal rotation in each hip occurred simultaneously to that hip approaching maximum flexion (Push leg; 5.6° internal rotation with 44.2° flexion; Lead leg; 10.8° internal rotation with 35.1° flexion). As the sprint start progressed, ‘at risk’ motion was increasingly exaggerated by increased hip rotation speed (Lead leg;+2.7° flexion/time-segment during recovery phase over the final 14% of the sprint).ConclusionDuring the sprint start, youth ice hockey players internally rotate while proceeding through hip flexion, displaying ‘at risk’ hip motion. This knowledge could be applied with related future findings to aid potential prevention of hip overuse injuries as youth hockey players mature and increase in skill level.
Translating theory into practice (and practice into theory) – does context influence sports injury prevention research?
Authors: Richardson P 
Published: March 2011

BackgroundSports injury prevention research, like many other fields, has difficulty translating research-based evidence into real-world practice. The ubiquitous theory-practice gap, historically portrayed as a ‘one-way’ knowledge-transfer issue, has recently been reconceptualised as a knowledge-production problem, suggesting a mismatch between the reductionist sense-making strategies which researchers and ‘real-world’ practitioners adopt to deal with the complexities of change, choice, communication, and culture. Sport, injury, prevention and research are dynamic, ecological phenomena occurring within socially-constructed communities of practice. Contextual factors influence the adoption of evidence-based recommendations in real-world settings, but do the theories that underpin sports injury prevention research practice take context into account?ObjectiveThis paper will explore the role of context in the theories commonly used to inform sports injury prevention research practice.DesignPeer-reviewed literature and major reference texts were searched to identify the theories and models most commonly cited and recommended for application in sports injury prevention research. The theory-practice gap literature from a range of other fields was also reviewed. The ‘contextual content’ of the theories used to inform sports injury prevention research was compared and contrasted with a number of contextual dimensions identified as consistent barriers to translation of evidence into practice in trans-disciplinary perspectives.ResultsThe theories most commonly cited by sports injury prevention researchers include behavioural, ecological and social dimensions that do reflect an understanding of the need to consider ‘context’ when trying to understand how to prevent sports injuries.ConclusionAlthough contextual elements are incorporated in the theories frequently cited by sports injury prevention researchers, lack of contextual ‘fit’ is still considered the major barrier to translating research knowledge into real-world practice. Is the ‘translation gap’ in the research process a problem of theory use or theory utility?
Posterior shear force and posterior tibial displacement using a sling bridge in patients with posterior cruciate ligament insufficiency
Authors: Sakai T , Koyanagi M , Nakata K , Fujisaki H , Yamagata T , Hidaka K , Suzuki Y , Nakamura N 
Published: March 2011

BackgroundRehabilitation training of hamstring muscle with deep knee flexion should be restricted following the posterior cruciate ligament (PCL) reconstruction because it stresses the PCL graft. To perform rehabilitation training of the hamstring muscle without the stress to the PCL, we have developed a sling bridge exercise (SB), which is a hamstring exercise with a sling at a lower leg to lift the buttocks in a supine position. Our hypothesis is that anterior traction force generated by a sling decrease strain on the PCL during SB.ObjectiveTo analyze posterior shear force and amount of posterior tibial displacement by the SB and compare with those by the conventional bridge (CB) exercise.DesignQuasi-experimental study.SettingControlled laboratory research.ParticipantsFive healthy male volunteers and one patient with PCL insufficiency.InterventionPosition of physical segments and force on floor were analyzed by a 3D motion capture system and force plate. Posterior tibial displacement was measured by lateral XP view of the knee during the exercises.Main outcome measurementsPosterior shear force of the knee was calculated by using a biomechanical musculoskeletal model. Posterior tibial displacement was measured by digitised XP.ResultsPosterior shear force of the healthy volunteers was 849.0 ± 322.5 N during CB and 360.6 ± 75.5 N during SB. In a patient with the PCL insufficiency, side-to side difference in posterior tibial displacement by SB (1.2 mm) was smaller than that of CB (3.3 mm).ConclusionThe SB hamstring exercise causes less posterior shear force and resulted in less posterior tibial displacement than a CB exercise. Therefore, a sling hamstring exercise is safer than a CB exercise in rehabilitation training for the patients with PCL reconstruction of the knee.
Atrial fibrillation in athletes: towards a changing therapeutic approach in the era of catheter ablation
Authors: Saoudi N , Arnoult M , Hugues T , Latcu D G , Popescu I , Ricard P , Rinaldi J P , Yaïci K , Zarqane N 
Published: March 2011

BackgroundThe Prevalence of atrial fibrillation (AF) is increasing and its incidence in professional and amateur athletes seems higher than in the general population (OR=2–10 after adjustment for other risk factors). A U shaped relationship of physical activity with incident AF suggests that the positive antiarrhythmic effects of sport are partially negated by prolonged heavy endurance exercise. AF is also more prevalent in middle-aged former competitive athletes.DesignA review of the literature of AF in athletes is presented. AF may be due to sympathetic activity, volume load during exercise, vagotonia at rest but also atrial hypertrophy and dilatation. Anticoagulation cannot be used in sporting activities with a risk of bodily collision. Rate control during AF is difficult to reach in athletes: -blockers are not well tolerated or even prohibited in some competitive sports, and digoxin or calcium antagonists are poorly effective during exertion. In paroxysmal AF athletes, the flecainide or propafenone ‘pill-in the pocket approach’ can be used, but transient sport practice limitations ensue.InterventionSeveral reports of the new pulmonary vein catheter ablation have demonstrated encouraging results. Using radiofrequency current, the latter is as efficacious in lone AF amateur athletes as in controls. Representative examples from our AF ablation patient database will be presented.ConclusionA review of the literature and our own experience suggest that catheter ablation of AF in athletes will probably develop in the near future. This is also supported by the recent European guidelines which state that ‘where appropriate, AF ablation should be considered to prevent recurrent AF in athletes' without requiring prior drug therapy.