Injury risk-workload associations in NCAA American college football

Objectives

To determine injury risk-workload associations in collegiate American Football.

Tibial acceleration and shock attenuation while running over different surfaces in a trail environment

ObjectivesIncreased tibial axial acceleration and reduced shock attenuation are associated with running injuries and are believed to be influenced by surface type. Trail running has increased in popularity and is thought to have softer surface properties than paved surface, but it is unclear if trail surfaces influence tibial acceleration and shock attenuation. The purpose of this study was to investigate peak triaxial and resultant tibial acceleration as well as axial and resultant shock attenuation among dirt, gravel, and paved surfaces.DesignFifteen recreational runners (12 females, 3 males, age = 27.7 ± 9.1 years) ran over dirt, gravel, and paved surfaces in a trail environment while instrumented with triaxial tibial and head accelerometers.MethodsDifferences between tri-planar peak tibial accelerations (braking, propulsion, axial, medial, lateral, and resultant) and shock attenuations (axial and resultant) among surface types were assessed with one-way ANOVAs with Bonferroni post-hoc tests.ResultsNo significant differences were found for tibial accelerations or shock attenuations among surface types (p > 0.05).ConclusionsDirt and gravel trail running surfaces do not have lower tibial accelerations or greater shock attenuation than paved surfaces. While runners are encouraged to enjoy the psychological benefits of trail running, trail surfaces do not appear to reduce loading forces associated with running-related injuries.     

Mechanisms of traumatic injury to the shoulder girdle in the Australian Football League

ObjectiveTo investigate mechanisms of shoulder girdle injuries and their impact on players from the Australian Football League (AFL).DesignRetrospective video analysis.MethodsTwo experienced sports physiotherapists (>10 years) examined video footage of shoulder complex injuries that occurred in the 2015 premiership season. Information obtained from video footage included activity prior to injury; mechanism of injury; arm, head and neck position and point of body contact at the time of injury. Player demographics and injury characteristics were obtained from club and media data.ResultsThe most common mechanism of injury was lateral contact (34.6%) followed by hyperflexion/ abduction of the shoulder (19.2%). Glenohumeral joint (GHJ) dislocations and subluxations were the most frequent diagnosis for all mechanisms of injury, and occurred in a variety of shoulder positions. Over 80% of injuries occurred with the arm below 100° of shoulder flexion or abduction. The most common activity prior to injury was ‘ball in dispute’ (34.6%). Lateral contact injuries had the highest overall severity (two-thirds of players missed >3 games) and over 50% of shoulder injuries required surgery. Players missed on average 5.1 season games due to shoulder injury.ConclusionThe lateral contact mechanism was the most common and severe mechanism of shoulder injury. Improved understanding of shoulder girdle injury mechanisms can help guide the use of preventative strategies and injury management programs in elite AFL players.     

Running coaches and running group leaders’ engagement with,and beliefs and perceived barriers to prehabilitation and injury prevention strategies for runners

ObjectivesTo identify which pre-and post-run injury risk reduction activities and prehabilitation (prehab) strategies Coaches and Running Group Leaders (Coaches/RGLs) engage in with runners; to explore their beliefs on why runners get injured; to identify Coaches/RGLs confidence providing injury prevention activities, and what they believe are effective for reducing risk of injury; to identify their perceived barriers to including prehab during running coaching/training.DesignSurvey; Participants: UK Coaches/RGLs (N = 100)Outcome measuresOnline questionnaire with open, closed and Likert scale questions.ResultsMost Coaches/RGLs performed active warm-ups (97%), cool-downs (94%),gave injury prevention advice (91%), and advice on recovery strategies (84%) during training. Fewer coaches/RGLs incorporated prehab (67%). Although they collectively exhibited a wide range of knowledge, individually there was less consistency and confidence providing this. Prehab was rated as very important for injury risk reduction, with supervision recommended to facilitate runner engagement. Coaches/RGLs found conflicting advice, time, environment, and resistance from runners as barriers to incorporating prehab into training.ConclusionCoaches/RGLs believe prehab is important for runners however lack of confidence and knowledge appeared to limit the wider inclusion of prehab with runners. Coaches/RGLs welcomed reputable information on prehab from evidence-based sources. This may assist in reducing injury.     

A pilot randomised controlled trial of eccentric exercise to prevent hamstring injuries in community-level Australian Football

Hamstring injuries are the most common injury sustained by Australian Football players. Eccentric training has been proposed as a potential preventative strategy. This pilot randomised controlled trial (RCT) evaluated the effectiveness of a pre-season eccentric training program for preventing hamstring injuries at the community level of Australian Football. Seven amateur clubs (n=220 players) were recruited. Players were randomised within clubs to the intervention (eccentric exercise) or control (stretching) groups and randomisation was stratified according to previous history of hamstring injury. Five exercise sessions were completed over a 12-week period, three during the pre-season and two during the first 6 weeks of the season. Compliance was recorded and players were monitored for the season to collect injury and participation data. There was no difference between the control (n=106) or intervention (n=114) groups with respect to baseline characteristics. Only 46.8% of all players completed at least two program sessions. Compliance was poorest for the intervention group. Intention-to-treat analysis suggested that players in the intervention group were not at reduced risk of hamstring injury (RR 1.2, 95% CI: 0.5, 2.8). When only control and intervention group players who participated in at least the first two sessions were analysed, 4.0% of intervention and 13.2% of control group players sustained a hamstring injury (RR 0.3, 95% CI: 0.1, 1.4; p=0.098). The findings suggest that a simple program of eccentric exercise could reduce the incidence of hamstring injuries in Australian Football but widespread implementation of this program is not likely because of poor compliance.     

Effects of prolonged walking with body borne load on knee adduction biomechanics

BackgroundSoldiers that suffer a service-related knee musculoskeletal injury routinely develop joint osteoarthritis. Knee osteoarthritis is a substantial and costly problem among soldiers, yet it is unknown how body borne load and duration of walking impact knee adduction biomechanics linked to progression and severity of osteoarthritis.Research questionThis study determined the adaptations in magnitude and variability of knee adduction joint angle (KAA) and moment (KAM) during prolonged walking with body borne load.MethodsThirteen recreationally active participants had knee biomechanics quantified while walking over-ground for 60-min at 1.3 m/s with three body borne loads (0, 15, and 30 kg). Magnitude and variability of KAA and KAM measures were quantified and submitted to a RM ANOVA to test the main effect and interactions between load (0, 15 and 30 kg) and time (0, 15, 30, 45 and 60 min).ResultsBody borne load increased peak KAM (p < 0.001), whereas time increased peak and range of KAA (both: p < 0.001). Specifically, peak KAM increased with each addition of body borne load (all: p < 0.025), and peak and range of KAA increased after 30 min of walking (both: p < 0.040). Neither body borne load, nor time had a significant effect on KAA or KAM variability (both: p > 0.05).SignificanceProlonged walking with heavy body borne load increased knee adduction biomechanics related to osteoarthritis. Adding heavy body borne load increased in peak KAM whereas duration of walking increased KAA, knee biomechanics that may increase loading of the medial knee joint compartment and risk of OA at the joint.     

Examination of the external and internal load indicators’ association with overuse injuries in professional soccer players

Objectives

Research in professional soccer focusing on the relevance of external and internal load indicators for injury prevention is scarce. This study examined the relationship between load indicators and overuse injuries.

The influence of sleep and training load on illness in nationally competitive male Australian Football athletes: A cohort study over one season

Objectives

To determine the incidence of illness, and identify the relationship between sleep, training load and illness in nationally competitive Australian football athletes. Second, to assess multivariate effect between training load and/or sleep variables.

In-season monitoring of hip and groin strength,health and function in elite youth soccer: Implementing an early detection and management strategy over two consecutive seasons

Objectives

The primary purpose of this study was to describe an early detection and management strategy when monitoring in-season hip and groin strength, health and function in soccer. Secondly to compare pre-season to in-season test results.

Injury surveillance and prevention practices across Rugby schools in Ireland

ObjectivesTo ascertain the extent of injury surveillance and prevention practices currently in operation and the availability of qualified personnel across Rugby playing schools in the Republic of Ireland.DesignCross-sectional survey design.SettingRugby playing schools across Ireland.ParticipantsThe Rugby games master, head Rugby coach or teacher/coach with knowledge of all Rugby activities in the school.ResultsNinety-three Rugby playing schools responded and reported 356 (97% male, 3% female) school Rugby teams. Rugby injuries were formally monitored in 86% of schools. Injury recorders were primarily coaches (61%). Physiotherapy provision was available in 28% of schools, 14% of schools provided access to a medical doctor and 44% of schools provided access to an S&C coach. Structured warm-ups were undertaken in 66% of schools, weekly gym sessions in 49% of schools and 31% of schools did not implement any formal injury prevention measures.ConclusionsInjury monitoring practices, medical personnel accessibility and the frequency of injury prevention practices varies considerably across Rugby playing schools in Ireland. Future injury surveillance and prevention systems should be suitable for use by non-medical personnel and reflect the structural organisation of the school Rugby game so that data are not solely representative of the elite, well-resourced schools.     

Nordic strength and history of hamstring injury in Australian Football League players

ObjectivesCompare hamstring strength between Australian Football League (AFL) players with and without a prior hamstring injury and determine the effect of the number of previous hamstring injuries, time since the last injury, and injury severity, on hamstring strength.DesignCross-sectional, retrospective.SettingAFL clubs.Participants124 AFL players.Main outcome measuresBilateral hamstring strength was assessed on a Nordbord (Vald Performance) during the Nordic Hamstring Exercise. Self-reported questionnaires were used to record previous hamstring injuries. Players were categorized into No Injury or Hamstring Injury groups. Previously injured players were subgrouped based on number of prior hamstring injuries (single or multiple), time since the last hamstring injury (≤1 or > 1-year ago), and hamstring injury severity (≤3 or > 3 matches missed).Results19 hamstring injuries were reported. Hamstring strength was not different between players with and without a history of hamstring injury when assessed in absolute (N) or relative (i.e., N.kg⁻¹) terms. No differences in strength were detected between hamstring injury subgroups when assessed in absolute or relative terms.ConclusionsAFL players that experienced a previous hamstring injury did not exhibit deficits in hamstring strength relative to their uninjured limb or players without a previous hamstring injury.     

Development of a preliminary evidence-based neuromusculoskeletal exercise guideline to reduce injury risk in the lower limb

Athletic participation growth has resulted in increased exposures and neuromusculoskeletal (NMSK) non-contact injuries. Based on current evidence, the primary objective of this literature review is to create a preliminary evidence-based NMSK exercise guideline, addressing these intrinsic modifiable risk factors. Systematic searches were conducted September 2014 prior to data extraction utilizing CINAHL Plus (1995 to September 2014), MEDLINE (1995 to September 2014), and Academic Search Premier (1995 to September 2014). A priori defined inclusion criteria were applied and included the following: (i) full text, (ii) published in English, (iii) peer-reviewed articles addressing injury risk of non-contact lower extremity injury, (iv) identified specific exercises aimed at reducing injury risk of non-contact lower extremity injury, were the key data extraction points of interest. 3163 potential articles were identified from the initial search, 3120 excluded with reason based on the exclusion criteria. Exclusion criteria was applied in the form of an eight item list summarized in table 2, 43 articles remained after search criteria were applied. Novel to the current body of knowledge, this review identified nine intrinsic modifiable risk factors of the NMSK system that were used as a foundation to create the exercise guideline consisting of 30 exercise techniques.     

Epidemiology of injury in English Professional Football players: A cohort study

ObjectiveTo estimate the current incidence and location of injury in English professional football.DesignProspective cohort study conducted over one competitive season (2015/16).SettingProfessional football players competing in the English Football League and National Conference.Participants243 players from 10 squads (24.3 ± 4.21 per squad).Main outcome measureInjury incidence, training and match exposure were collected in accordance with the international consensus statement on football injury epidemiology.Results473 injuries were reported. The estimated incidence of injury was, 9.11 injuries/1000 h of football related activity. There was a higher incidence of injury during match play (24.29/1000 h) compared to training (6.84/1000 h). The thigh was the most common site of injury (31.7%), muscle strains accounted for 41.2% of all injuries. The hamstrings were the most frequently strained muscle group, accounting for 39.5% of all muscle strains and 16.3% of all injuries. Moderate severity injuries (8–28 days) were the most common (44.2%).ConclusionsIncidence of injury has increased over the last 16 years with muscle strains remaining the most prevalent injury. The hamstrings remain the most commonly injured muscle group.     

Risk of acute and overuse injuries in youth elite soccer players: Body size and growth matter

ObjectivesThis study investigated anthropometric measures and growth as risk factors for overuse and acute injuries in younger (U10–U12) and older (U13–U15) elite level soccer players.DesignProspective cohort study.MethodsHeight, weight, and sitting height were measured at the start and the end of the 2016–2017 competitive season and growth velocities were calculated. Throughout the season, injuries were registered continuously by the (para-)medical staff of the included clubs. We analyzed the injury risk using multilevel Poisson regression models, accounting for club and team clustering.ResultsOf the included 314 players (11.7 ± 1.7 years of age), 160 players sustained 133 overuse and 163 acute injuries (i.e. 106 injuries in 69 players of the younger group, 190 in 91 players of the older group). In the younger group, risk of overuse injuries was associated with an increase in leg length over the season (incidence rate ratio (IRR) 1.620 [95% CI 1.230–2.117]) and risk of acute injuries with relatively younger age (IRR 1.003 [95% CI 1.000–1.006]). In the older group, a higher leg length was associated with an increased risk of overuse injuries (IRR 1.055 [95% CI 1.011–1.108]), and a higher weight and a lower growth rate with an increased risk of acute injuries (IRR 1.043 [95% CI 1.021–1.067] and 0.903 [95% CI 0.831–0.981], respectively).ConclusionsInjury risk factors differ by age group and type of injury. The age-specific anthropometric and growth-related risk factors should be monitored and these risk profiles should be considered to manage injury risk effectively.     

Harmful association of sprinting with muscle injury occurrence in professional soccer match-play: A two-season,league wide exploratory investigation from the Qatar Stars League

ObjectivesTo investigate the impact of physical efforts performed in the period preceding activity as a potential risk factor of muscle injury during match-play within a sample of professional soccer players.DesignObservational cohort study.MethodsMatch load (running [>14.4–19.8 km/h], high-speed running [>19.8–25.2 km/h], sprinting [>25.2 km/h], leading and explosive sprint type) averaged in 1-min and 5-min periods prior to an event or non event for 29 professional outfield soccer players. Conditional logistic and Poisson regression models estimated the relationship between load and injury for a 2 within-subject standard deviation in match load or 1-action increment in the number of sprinting activities, respectively. Associations were deemed beneficial or harmful based on non-overlap of the 95% confidence intervals against thresholds of 0.90 and 1.11, respectively.ResultsAn increment in sprinting distance [+2-SDs = 11 m] covered over a 1-min period (odds ratio [OR]: 1.22, 95%CI, 1.12 to 1.33) increased the odds of muscle injury.ConclusionsOur study provides novel exploratory evidence that the volume of sprinting during competitive soccer match-play has a harmful association with muscle injury occurrence.     

Association between pre-participation characteristics and risk of injury amongst pre-professional dancers

Study designProspective Cohort Study.BackgroundFew investigations utilize evidence-informed pre-participation evaluation, inclusive injury definitions, and prospective surveillance to identify risk factors for dance-related injuries.ObjectiveTo evaluate pre-participation characteristics that may be associated with greater odds of dance-related musculoskeletal complaints in pre-professional dancers.MethodsFull-time pre-professional ballet [n = 85, 77 females, median (range) age 15-years (11–19)] and contemporary [n = 60, 58 females, 19-years (17–30)] dancers underwent pre-participation evaluation: baseline questionnaire, coping skills, body mass index, bone mineral density, ankle range-of-motion, active standing turnout, lumbopelvic control, and balance tests. Self-reported complaints (any physical problem making dance participation difficult, irrespective of medical attention or time-loss) were captured weekly via online questionnaires for one academic year. Self-reported musculoskeletal complaints were recorded weekly (yes/no). Potential risk factors were identified a-priori through systematic review. Associations between potential risk factors and musculoskeletal complaints were examined with generalized linear mixed method regression models.ResultsResponse rate was 99%, with 81% of dancers reporting at least one musculoskeletal complaint. Of 1521 complaints (19% first-time, 81% ongoing), the ankle (22%), knee (21%), and foot (12%) accounted for the majority. Injury history [odds ratio (OR) 7.37 (95% CI 3.41, 15.91)] and previous week's dance hours [OR 1.02 (1.01, 1.03)] were associated with dance-related musculoskeletal complaints.ConclusionsPrevalence of musculoskeletal complaints amongst pre-professional dancers is high and associated with injury history and training volume. Further understanding of the relationship between training load and injury is needed, with particular consideration of the dynamic and recursive nature of dance injury etiology.Level of EvidenceTherapy / Prevention, Aetiology / Harm, level 2b.     

Multi-segment spine range of motion in dancers with and without recent low back pain

BackgroundAltered spine kinematics are a common in people with LBP. This may be especially true for populations such as dancers, who are required to perform repetitive movements of the spine, although this remains unclear.Research questionDo dancers with recent LBP display altered spine kinematics compared to their asymptomatic counterparts?MethodsA cross-sectional study of multi-segment spine kinematics was performed. Forty-seven pre-professional and professional female dancers either with LBP in the past two months (n = 26) or no LBP in the past 12 months (n = 21) participated. Range of motion (ROM) during standing side bending, seated rotation, and walking gait were compared.ResultsFemale dancers with LBP displayed reduced upper lumbar transverse plane ROM in seated rotation (Effect Size (ES)= −0.61, 95% Confidence Interval (CI): −1.20, 0.02, p = 0.04), as well as reduced lower lumbar transverse plane ROM (ES=−0.65, 95% CI: −1.24, −0.06, p = 0.03) in gait. However, there was increased lower thoracic transverse plane ROM (ES = 0.62, 95% CI: 0.04, 1.21, p = 0.04) during gait. No differences in the frontal plane were observed.SignificanceAltered transverse plane spine kinematics were evident in dancers with recent LBP for select segments and tasks. This may reflect a protective movement strategy. However, as the effect sizes of observed differences were moderate, and the total number of differences between groups was small, collectively, it seems only subtle differences in spine kinematics differentiate dancers with LBP to dancers without.     

The role of insurance data in setting priorities for netball injury prevention strategies

The aim of this study was to investigate insurance records for a one-year period to determine the injury frequencies and costs associated with different age groups in netball. The insurance records for all netball claims made during 1999 in Victoria were obtained from the insurer and entered into a database. The overall injury rate was 9.49 injuries per 1000 players, with 829 claims for injuries filed with the insurance company. Of all injuries claimed for, 85.3% were to the lower limb, 8.7% to the upper limb, 3.1% to the spine/torso and 2.9% to the head and face. Lower limb injuries accounted for 85.4% of costs, upper limb injuries 10.7% and head/neck/torso injuries 3.9% of total injury costs. Knee injuries accounted for 56.9% of total costs, with ankle and calf/Achilles injuries costing 12.7 and 11.8% of total costs, respectively. Injury prevention strategies should therefore be directed to three main injuries taking into account costs and incidence. These injuries were: ankle sprains, knee ligament sprains and Achilles tendon strains. Specifically, the prevention program for Achilles injuries should be directed to the >25 years age groups.