Merete Møller

Injury risk in Danish youth and senior elite handball using a new SMS text messages approach

Objective To assess the injury incidence in elite handball, and if gender and previous injuries are risk factors for new injuries. Methods Cohort study of 517 male and female elite handball players (age groups under (u)16, u-18 and senior). Participants completed a web survey establishing injury history, demographic information and sports experience, and provided weekly reports of time-loss injuries and handball exposure for 31 weeks by short message service text messaging (SMS). Injuries were further classified by telephone interview. Results The weekly response rate ranged from 85% to 90% illustrating the promise of the SMS system as a tool in injury surveillance. Of 448 reported injuries, 165 injuries (37%) were overuse injuries and 283 (63%) traumatic injuries. Knee (19%) and ankle (29%) were the most common traumatic injuries. The injury incidence during match play was 23.5 (95% CI 17.8 to 30.4), 15.1 (95% CI 9.7 to 22.2), 11.1 (95% CI 7.0 to 16.6) injuries per 1000 match hours among senior, u-18 and u-16 players, respectively. U-18 male players had an overall 1.76 (95% CI 1.10 to 2.80) times higher risk of injury compared to females. Having had two or more previous injuries causing absence from handball for more than 4 weeks increased the risk of new injury in the u-16 group (IRR: 1.79 (95% CI 1.03 to 3.11)–2.23 (95% CI 1.22 to 4.10)). Conclusion The incidence of time-loss injuries in elite handball was higher during match play than previously reported in recreational handball. Previous injuries were a risk factor for new injuries among u-16 players. Male players had a significant higher injury rate in the u-18 group.

High Injury Incidence in Adolescent Female Soccer

Background: Previous studies report varying rates of time-loss injuries in adolescent female soccer, ranging from 2.4 to 5.3 per 1000 athlete-exposures or 2.5 to 3.7 per 1000 hours of exposure. However, these studies collected data using traditional injury reports from coaches or medical staff, with methods that significantly underestimate injury rates compared with players’ self-reports. Purpose: The primary aim was to investigate the injury incidence in adolescent female soccer using self-reports via mobile telephone text messaging. The secondary aim was to explore the association between soccer exposure, playing level, and injury risk. Study Design: Descriptive epidemiology study and cohort study; Level of evidence, 2 and 3. Methods: During a full adolescent female soccer season in Denmark (February-June 2012), a population-based sample of 498 girls aged 15 to 18 years was included in the prospective registration of injuries. All players were enrolled on a team participating in Danish Football Association series. Soccer injuries and exposure were reported weekly by answers to standardized text message questions, followed by individual injury interviews. Soccer exposure and playing levels were chosen a priori as the only independent variables of interest in the risk factor analyses. Injury rates and relative risks were estimated using Poisson regression. Generalized estimation equations were used to take into account that players were clustered within teams. Results: There were 498 players who sustained a total of 424 soccer injuries. The incidence of injuries was 15.3 (95% CI, 13.1-17.8), the incidence of time-loss injuries was 9.7 (95% CI, 8.2-11.4), and the incidence of severe injuries was 1.1 (95% CI, 0.7-1.6) per 1000 hours of soccer exposure. Higher average exposure in injury-free weeks was associated with a lower injury risk (P value for trend <.001), and players with low exposure (≤1 h/wk) were 3 to 10 times more likely to sustain a time-loss injury compared with other players (P < .01). Playing level was not associated with the risk of time-loss injuries (P = .18). Conclusion: The injury incidence in adolescent female soccer is high, and this includes many severe injuries. Players with low soccer participation (≤1 h/wk) have a significantly higher injury risk compared with players participating more frequently.

Handball load and shoulder injury rate: A 31-week cohort study of 679 elite youth handball players

Background Knowledge of injury patterns, an essential step towards injury prevention, is lacking in youth handball. Aim To investigate if an increase in handball load is associated with increased shoulder injury rates compared with a minor increase or decrease, and if an association is influenced by scapular control, isometric shoulder strength or glenohumeral range of motion (ROM). Methods 679 players (14–18 years) provided weekly reports on shoulder injury and handball load (training and competition hours) over 31 weeks using the SMS, phone and medical examination system. Handball load in a given week was categorised into (1) <20% increase or decrease (reference), (2) increase between 20% and 60% and (3) increase >60% relative to the weekly average amount of handball load the preceding 4 weeks. Assessment of shoulder isometric rotational and abduction strength, ROM and scapular control was performed at baseline and midseason. Results An increase in handball load by >60% was associated with greater shoulder injury rate (HR 1.91; 95% CI 1.00 to 3.70, p=0.05) compared with the reference group. The effect of an increase in handball load between 20% and 60% was exacerbated among players with reduced external rotational strength (HR 4.0; 95% CI 1.1 to 15.2, p=0.04) or scapular dyskinesis (HR 4.8; 95% CI 1.3 to 18.3, p=0.02). Reduced external rotational strength exacerbated the effect of an increase above 60% (HR 4.2; 95% CI 1.4 to 12.8, p=0.01). Conclusions A large increase in weekly handball load increases the shoulder injury rate in elite youth handball players; particularly, in the presence of reduced external rotational strength or scapular dyskinesis.

When is a study result important for athletes, clinicians and team coaches/staff?

How do you know if the results of a particular study are important to your team, your patients or your community? A result that is statistically significant is not necessarily a meaningful target for sports injury prevention or a treatment strategy.1–3 And if statistical significance is not enough to determine ‘importance’ or meaningfulness, then what is? ### Box 1 Definition: Minimal important difference (MID) Minimal important difference (MID) is the smallest change in sports injury risk or treatment outcome that an athlete, a player, a coach, a clinician and/or team staff would identify as important. The size of MID is context-specific and a study result may be identified as important for some and non-important for others. We aim to shed light on this important topic in the first of a series of editorials that will help clinicians and team staff interpret studies more critically and confidently. First, a measure of association (eg, a relative risk or an absolute risk difference) and its precision (eg, 95% CIs) allows for appropriate evaluation of study results.1 Next, a size of an association should be equal to or exceed a minimal important difference (MID) (box 1) that would affect practice. In this light, the question remains: is it possible to identify a MID in sports injury articles regardless of the measure of association used? In this editorial, we argue that the choice of measure has consequences for the ability to …

Validity of the SMS, Phone, and medical staff Examination sports injury surveillance system for time-loss and medical attention injuries in sports

The accurate measurement of sport exposure time and injury occurrence is key to effective injury prevention and management. Current measures are limited by their inability to identify all types of sport‐related injury, narrow scope of injury information, or lack the perspective of the injured athlete. The aims of the study were to evaluate the proportion of injuries and the agreement between sport exposures reported by the SMS messaging and follow‐up telephone part of the SMS, Phone, and medical staff Examination (SPEx) sports injury surveillance system when compared to measures obtained by trained on‐field observers and medical staff (comparison method). We followed 24 elite adolescent handball players over 12 consecutive weeks. Eighty‐six injury registrations were obtained by the SPEx and comparison methods. Of them, 35 injury registrations (41%) were captured by SPEx only, 10 injury registrations (12%) by the comparison method only, and 41 injury registrations (48%) by both methods. Weekly exposure time differences (95% limits of agreement) between SPEx and the comparison method ranged from −4.2 to 6.3 hours (training) and −1.5 to 1.0 hours (match) with systematic differences being 1.1 hours (95% CI 0.7 to 1.4) and −0.2 (95% CI −0.3 to −0.2), respectively. These results support the ability of the SPEx system to measure training and match exposures and injury occurrence among young athletes. High weekly response proportions (mean 83%) indicate that SMS messaging can be used for player measures of injury consequences beyond time‐loss from sport. However, this needs to be further evaluated in large‐scale studies.

Self-reported previous knee injury and low knee function increase knee injury risk in adolescent female football.

Knee injuries are common in adolescent female football. Self‐reported previous knee injury and low Knee injury and Osteoarthritis Outcome Score (KOOS) are proposed to predict future knee injuries, but evidence regarding this in adolescent female football is scarce. The aim of this study was to investigate self‐reported previous knee injury and low KOOS subscale score as risk factors for future knee injuries in adolescent female football. A sample of 326 adolescent female football players, aged 15–18, without knee injury at baseline, were included. Data on self‐reported previous knee injury and KOOS questionnaires were collected at baseline. Time‐loss knee injuries and football exposures were reported weekly by answers to standardized text‐message questions, followed by injury telephone interviews. A priori, self‐reported previous knee injury and low KOOS subscale scores (< 80 points) were chosen as independent variables in the risk factor analyses. The study showed that self‐reported previous knee injury significantly increased the risk of time‐loss knee injury [relative risk (RR): 3.65, 95% confidence (CI) 1.73–7.68; P < 0.001]. Risk of time‐loss knee injury was also significantly increased in players with low KOOS subscale scores (< 80 points) in Activities of Daily Living (RR: 5.0), Sport/Recreational (RR: 2.2) and Quality of Life (RR: 3.0) (P < 0.05). In conclusion, self‐reported previous knee injury and low scores in three KOOS subscales significantly increase the risk of future time‐loss knee injury in adolescent female football.

The SMS, Phone and medical Examination sports injury surveillance (SPEx) system is a feasible and valid approach to measuring handball exposure, injury occurrence and consequences in elite youth sport

Current methods of sports injury surveillance are limited by lack of medical validation of self‐reported injuries and/or incomplete information about injury consequences beyond time loss from sport. The aims of this study were to (a) evaluate the feasibility of the SMS, Phone, and medical Examination injury surveillance (SPEx) system (b) to evaluate the proportion of injuries and injury consequences reported by SPEx when compared to outcomes from a modified version of the Oslo Sports Trauma Research Centre (OSTRC) Overuse Injury Questionnaire. We followed 679 elite adolescent handball players over 31 weeks using the SPEx system. During the last 7 weeks, we also implemented a modified OSTRC questionnaire in a subgroup of 271 players via telephone interviews. The weekly response proportions to the primary SPEx questions ranged from 85% to 96% (mean 92%). SMS responses were received from 79% of the participants within 1 day. 95% of reported injuries were classified through the telephone interview within a week, and 67% were diagnosed by medical personnel. Comparisons between reported injuries from SPEx and OSTRC demonstrated fair (κ = 39.5% [25.1%‐54.0%]) to substantial prevalence‐adjusted bias‐adjusted kappa (PABAK = 66.8% [95% CI 58.0%‐75.6%]) agreement. The average injury severity score difference between SPEx and the OSTRC approach was −0.2 (95% CI −3.69‐3.29) of possible 100 with 95% limits of agreement from(−14.81‐14.41).

Throwing Biomechanics: Aspects of Throwing Performance and Shoulder Injury Risk

This chapter will describe the biomechanics of the upper limb. The main focus will be on the biomechanics of throwing; how the coordination of the trunk, upper arm, lower arm and wrist is important for the optimal throwing performance; and how the observed variations in throwing technique may influence the performance. The last part of the chapter will further discuss how the throwing technique will influence the biomechanical loading of the joints and describe, based on current evidence, how also the overall load in combination with neuromuscular control and strength of the muscles around the scapula and shoulder joint influence the risk factors for throwing related injuries in handball.

Implementing Handball Injury Prevention Exercise Programs: A Practical Guideline

The efficacy of injury prevention exercise programs (IPEPs) for handball has been established in large-scale randomized controlled trial. Despite this, these programs are currently not implemented in a real-world context.

Training Load Issues in Young Handball Players

As in many youth sports, handball provides kids and adolescents with the opportunity to develop physical fitness including coordination, speed, endurance, agility, power and strength as well as develop social skills. Indisputable, participating in sports activities from a young age has numerous health and social benefits. However, this development of physical fitness requires that the player can adapt to the applied training load. Otherwise, there is an increased risk of injuries or non-functional overreaching. Further, there is also a chance that the player will lack the motivation to continue with handball, due to either too much pressure or persistent or recurrent injuries. In this chapter, we will outline potential risk scenarios of overload specifically in the young handball player aged 12–19 and how to address these risk scenarios.