Return to play after hamstring injuries in football (soccer): a worldwide Delphi procedure regarding definition, medical criteria and decision-making

A new field-test for assessing the medial and lateral hamstring strength at long-muscle length

This research investigates the influence of tibial rotations with knee flexion (KF) on the electromyographic (EMG) activities of hamstring muscles (HM) groups and the strength ratio between the medial and lateral rotation of the tibia. A cross-sectional design was employed to assess muscle activity, isometric strength and reliability. The research was conducted in a controlled laboratory environment. Thirty-six amateur male athletes were recruited as volunteers. The measures included peak muscle activity of the semitendinosus and biceps femoris long head, the knee flexors' isometric strength ratio and reliability. The isometric strength ratios of medial (MR) to lateral (LR) tibial rotations were 0.94 ± 0.17 at 90°, and 0.93 ± 0.10 at both 60° and 30° of KF angulation. Tibial position significantly influenced knee flexion strength as well as HM activity, irrespective of KF angulation. Specifically, biceps femoris activity increased by 33.6% in LR compared to MR, while semitendinosus activity increased by 22.6% in MR compared to LR. The Knee-Rotation test (KR-test) can be a valuable tool for evaluating both HM groups (ICC >0.87), and identifying the primary target for strengthening purposes during the injury prevention process. It provides insights for effective rehabilitation and training interventions.

Return-to-play criteria following a hamstring injury in professional football: a scoping review

The present scoping review aims to describe the available criteria to determine Return-To-Play (RTP), propose methodological considerations and new research questions, and provide information to help practitioners in professional football make informed decisions regarding RTP following a hamstring strain injury (HSI) in professional male football. The following electronic databases were searched: PubMed, MEDLINE, web of science and SPORTDiscus using keywords related to HSI in elite football. All types of studies in English reporting at least one RTP criterion for professional football players who sustained an HSI were included. In total, 19 studies met the inclusion criteria. RTP criteria were divided into three categories: clinical, strength and performance criteria. Clinical criteria were also divided into sub-categories: absence of pain, hamstring flexibility, medical staff clearance, psychological readiness, surgeon's opinion and imaging. Practitioners working in professional male football could benefit from using a combination of criteria in their RTP battery of tests.

Injury risk factors and their priority for mitigation in women's netball: a systematic review and Delphi consensus

This study aimed to establish consensus on injury risk factors in netball via a combined systematic review and Delphi method approach. A systematic search of databases (PubMed, Scopus, MEDLINE, SPORTDiscus and CINAHL) was conducted from inception until June 2023. Twenty-four risk factors were extracted from 17 studies and combined with a three-round Delphi approach to achieve consensus. In round one, experts listed perceived risk factors for injury in netball which were combined with the risk factors identified via the systematic review. In round two and round three, experts rated their level of agreement with each risk factor on a 5-point Likert scale (1, strongly disagree to 5, strongly agree). Consensus was defined as ≥80% agreement (with<10% in disagreement). In round three, experts also rated the priority for mitigating the risk factor (1, very low to 5, very high). Nineteen experts participated in round one and round two, and 16 participated in round three (response rate 84%). One-hundred and nine risk factors for injury were identified by the systematic review and experts combined. Sixty-one risk factors reached consensus, categorised into five groups: 'individual characteristics' (n=22), 'lifestyle' (n=11), 'training and competition' (n=14), 'sport science and medical provision' (n=6) and 'facilities and equipment' (n=8). 'Poor landing technique/mechanics' had a median (IQR) mitigation priority rating of 5 (1), while all others had median ratings of 3-4.5. This study identifies a range of risk factors for injury, provides focus areas for injury prevention and highlights the importance of a multidisciplinary approach to injury mitigation in netball.

Current Definitions of Return to Play After Medial Ulnar Collateral Ligament Injuries and Surgery in Professional Baseball Players Prohibit Cross-Study Comparison: A Systematic Review

PURPOSE

To assess the definitions of return to play (RTP) and return to same level of play (RTSP) used in literature describing ulnar collateral ligament (UCL) injuries in professional baseball players.

METHODS

A systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, Embase, Web of Science, and Cochrane databases were queried to identify all articles that included UCL injuries between January 2002 and October 2022. Studies of only Major League Baseball (MLB) and Minor League Baseball (MiLB) players were included and summarized descriptively.

RESULTS

We included 29 articles (24 reporting RTP, 23 reporting RTSP). Minimum level of play was not included in 46% of RTP definitions and 26% of RTSP definitions; when defined, return to MLB level only was most common in RTP definitions (25%) and return to either MLB or MiLB level was most common in RTSP definitions (39%). Time to return was frequently not included (96% of RTP and RTSP definitions); when defined, return within 2 full seasons after injury was the sole definition used. Duration of play after return was frequently not included (50% and 61%, respectively); when defined, a one game minimum was most used (42% and 17%, respectively). No study used performance measures (e.g., strikeouts, earned run average, etc.) to define RTP or RTSP.

CONCLUSIONS

Definitions of RTP and RTSP in the UCL injury literature for professional baseball players of all positions are vague, heterogenous, and prohibit cross-study comparison.

CLINICAL RELEVANCE

The present study investigates the definitions for RTP and RTSP used across professional baseball UCL injury literature in hopes of identifying common threads to promote future cross-study comparison.

Classification of myo-connective tissue injuries for severity grading and return to play prediction: A scoping review

OBJECTIVES

To conduct a systematic literature search to identify currently used classifications of acute non-contact muscle injuries in sporting adults.

DESIGNS

Scoping review.

METHODS

A systematic literature search from January 1, 2010 to April 19, 2022 of Medline and SPORTDiscus yielded 13,426 articles that were screened for eligibility. Findings from included studies were qualitatively synthesized. Classifications and their grading, as well as outcomes and definitions were extracted.

RESULTS

Twenty-four classifications were identified from the 37 included studies, most of which had low evidence study designs. Majority (57 %) of classifications were published after 2009 and were mostly developed for hamstring or other lower limb injuries. The six most cited classifications accounted for 70 % of the reports (BAMIC, modified Peetrons, Munich, Cohen, Chan and MLG-R). Outcome reporting was sparse, making it difficult to draw conclusions. Still, significant relationships between grading and time to return to play were reported for the BAMIC, modified Peetrons, Munich and Cohen classifications. Other classifications either had a very low number of reported associations, reported no associations, reported inconclusive associations, or did not report an assessment of the association. Other outcomes were poorly investigated.

CONCLUSIONS

There is no agreed-upon use of muscle classification, and no consensus on definitions and terminology. As a result, reported outcomes and their relationship to severity grading are inconsistent across studies. There is a need to improve the generalizability and applicability of existing classifications and to refine their prognostic value. High-level evidence studies are needed to resolve these inconsistencies.

Is limb asymmetry an intrinsic risk factor for time-loss groin injury in professional male soccer players?

OBJECTIVES

To provide normative values for between-limb asymmetry of hip strength and range of motion (ROM) in professional male soccer players and evaluate the relationship between these asymmetries and groin injury.

DESIGN

Secondary analysis of a prospective cohort study.

METHODS

A total of 438 professional male soccer players underwent musculoskeletal screening, injury and exposure surveillance over two consecutive seasons. Between-limb asymmetry for two hip strength (eccentric adduction and abduction) and six ROM measures were calculated, and normal asymmetry considered within 1 standard deviation (SD) of the mean. Cox proportional hazard regression analysis estimated the association between asymmetry and time-loss groin injury.

RESULTS

Normal asymmetry ranged between 0.3% and 27.3% across strength and ROM variables. No association was found between groin injuries and asymmetry in eccentric hip adduction (HR = 0.99, 95%CI = 0.98-1.00; p = 0.167) or abduction strength (HR = 1.00, 95%CI = 0.99-1.01; p = 0.745). For five of the six ROM measures, no association with groin injuries were determined. A statistically significant, though likely clinically irrelevant, association was found between groin injury and dominant leg total hip rotation ROM (HR = 1.03, 95% CI = 1.00-1.05; p = 0.040).

CONCLUSION

Normal hip strength and ROM asymmetry ranged between -27 and +20%. No clinically relevant associations were found between asymmetry in hip strength or ROM and time-loss groin injuries.

LEVEL OF EVIDENCE: 2

Multiligament knee injury (MLKI): an expert consensus statement on nomenclature, diagnosis, treatment and rehabilitation

Multiligament knee injuries (MLKIs) represent a broad spectrum of pathology with potentially devastating consequences. Currently, disagreement in the terminology, diagnosis and treatment of these injuries limits clinical care and research. This study aimed to develop consensus on the nomenclature, diagnosis, treatment and rehabilitation strategies for patients with MLKI, while identifying important research priorities for further study. An international consensus process was conducted using validated Delphi methodology in line with British Journal of Sports Medicine guidelines. A multidisciplinary panel of 39 members from 14 countries, completed 3 rounds of online surveys exploring aspects of nomenclature, diagnosis, treatment, rehabilitation and future research priorities. Levels of agreement (LoA) with each statement were rated anonymously on a 5-point Likert scale, with experts encouraged to suggest modifications or additional statements. LoA for consensus in the final round were defined 'a priori' if >75% of respondents agreed and fewer than 10% disagreed, and dissenting viewpoints were recorded and discussed. After three Delphi rounds, 50 items (92.6%) reached consensus. Key statements that reached consensus within nomenclature included a clear definition for MLKI (LoA 97.4%) and the need for an updated MLKI classification system that classifies injury mechanism, extent of non-ligamentous structures injured and the presence or absence of dislocation. Within diagnosis, consensus was reached that there should be a low threshold for assessment with CT angiography for MLKI within a high-energy context and for certain injury patterns including bicruciate and PLC injuries (LoA 89.7%). The value of stress radiography or intraoperative fluoroscopy also reached consensus (LoA 89.7%). Within treatment, it was generally agreed that existing literature generally favours operative management of MLKI, particularly for young patients (LoA 100%), and that single-stage surgery should be performed whenever possible (LoA 92.3%). This consensus statement will facilitate clinical communication in MLKI, the care of these patients and future research within MLKI.

A Novel Method to Measure Dual-Task Capacity in Young Football Players: A Preliminary Study

CONTEXT

When deciding to return to sport, in the literature, evaluations based on physical abilities have usually been used. However, in the current literature, we have been urged to use more than physical performance evaluations. Classical dual-task testing methods do not simulate in-game loads and cannot sufficiently measure football players' dual-task capacity.

OBJECTIVE

To create a dual-task test that would simulate football players' in-game situations and measure their capacity.

DESIGN

Cross-sectional study.

SETTING

Football pitch.

PATIENTS OR OTHER PARTICIPANTS

Twenty-two football players (age = 17.37 ± 0.52 years) who played in a professional club (U19, elite league) were recruited for our study.

INTERVENTION(S)

A novel dual-task test with questions containing scenarios from a football game to cognitively load players while they are performing a modified t test.

MAIN OUTCOME MEASURE(S)

After the warmup period, participants attended 4 tests in random order: juggling (foot), speed dribbling, long passing, and novel dual-task tests.

RESULTS

No significant relationship was found between physical performance parameters and dual-task parameters (all P > .05). A significant increase was found in the completion time of the modified t test when performed under the dual-task condition (Z = -7.568, P < .001). The increase in completion time was 2.14 ± 1.29 seconds. This duration difference was calculated as 22.79% ± 14.58%, as dual-task cost.

CONCLUSIONS

Our test provides a new method to measure athletes' dual-task capacity, which is not related to physical performance and cannot be measured with current tests. This test also showed players with lower dual-task ability could not keep up their performance under dual-task conditions, such as passing a ball to a teammate when being pressed by an opponent. Players with good dual-task ability could maintain their performance (were affected only up to 10%); players with poor dual-task ability could not maintain their performance and were affected by up to 50% (with a mean of 22.79%).

Smaller Biceps Femoris Aponeurosis Size in Legs with a History of Hamstring Strain Injury

Biceps femoris long head (BFLH) aponeurosis size was compared between legs with and without prior hamstring strain injury (HSI) using two approaches: within-group (injured vs. uninjured legs of previous unilateral HSI athletes) and between-group (previously injured legs of HSI athletes vs. legs of No Prior HSI athletes). MRI scans were performed on currently healthy, competitive male athletes with Prior HSI history (n=23;≥1 verified BFLH injury; including a sub-group with unilateral HSI history; most recent HSI 1.6±1.2 years ago) and pair-matched athletes with No Prior HSI history (n=23). Anonymized axial images were manually segmented to quantify BFLH aponeurosis and muscle size. Prior unilateral HSI athletes' BFLH aponeurosis maximum width, aponeurosis area, and aponeurosis:muscle area ratio were 14.0-19.6% smaller in previously injured vs. contralateral uninjured legs (paired t-test, 0.008≤P≤0.044). BFLH aponeurosis maximum width and area were also 9.4-16.5% smaller in previously injured legs (n=28) from Prior HSI athletes vs. legs (n=46) of No Prior HSI athletes (unpaired t-test, 0.001≤P≤0.044). BFLH aponeurosis size was smaller in legs with prior HSI vs. those without prior HSI. These findings suggest BFLH aponeurosis size, especially maximum width, could be a potential cause or consequence of HSI, with prospective evidence needed to support or refute these possibilities.

3.0-Tesla MRI Observation at Return to Play After Hamstring Injuries

OBJECTIVE

To describe 3.0-Tesla (T) magnetic resonance imaging (MRI) findings of hamstring muscles in clinically recovered athletes who were cleared for return to play (RTP).

DESIGN

Prospective observational study.

SETTING

Hospital.

PARTICIPANTS

Athletes (amateur and professional) who were cleared for RTP after hamstring injury. Fifty-eight participants were included in the analysis.

INDEPENDENT VARIABLES

3-T MRI at baseline (within 7 days from initial injury) and MRI at RTP (within 10 days of RTP).

MAIN OUTCOME MEASURES

Injury location, grade of injury (modified Peetrons and British Athletics Muscle Injury Classification/BAMIC), presence and the extent of intramuscular signal abnormality, intramuscular tendon disruption, and thickness. Reinjuries within 1 year of RTP were recorded.

RESULTS

Magnetic resonance images at RTP showed that 55 (95%) participants had intramuscular increased signal intensity (edema) and 44 (76%) participants had intramuscular abnormal low-signal intensity (suggesting fibrosis) on MRI. There was an overall reduction of injury grades according to the modified Peetrons and BAMIC classification at initial injury to RTP. Three (5%) participants had no abnormal signal intensities (grade 0 or grade 0A) on MRI at RTP. Intramuscular tendon disruption, waviness, and tendon thickening were present at RTP in, respectively, 22 (38%), 15 (26%), and 36 (62%). We recorded 3 (5%) reinjuries.

CONCLUSIONS

At RTP, 3.0-T MRI shows high percentages of MRI abnormalities (edema, fibrosis, and intramuscular tendon disruption and thickening). We conclude that complete normalization of 3.0-T MRI is not expected for RTP decision after a hamstring injury. Its possible association with reinjury risk has to be determined in larger cohorts.

The challenge of thigh tendon reinjuries: an expert opinion

This review critically examines the issue of thigh tendon reinjury in athletes, drawing on recent advancements and diverse perspectives in sports medicine. The findings underscore the paramount importance of an early and accurate diagnosis, which significantly influences treatment efficacy and rehabilitation outcomes. We explore the intricacies of tendon anatomy and the mechanisms underlying injuries, highlighting how these factors interplay with athlete-specific risk profiles to affect reinjury rates. A major finding from the review is the necessity for individualized rehabilitation approaches that integrate both traditional methods and emerging technologies. These technologies show promise in enhancing monitoring and facilitating precise adjustments to rehabilitation protocols, thus improving recovery trajectories. Additionally, the review identifies a common shortfall in current practices - premature to play (RTP) - which often results from inadequate adherence to tailored rehabilitation strategies or underestimation of the injury's severity. Such premature RTP significantly heightens the risk of further injury. Through this synthesis of contemporary research and expert opinion, the review advocates for a multidisciplinary approach in managing thigh tendon injuries, emphasizing the need for ongoing research to refine RTP criteria and optimize rehabilitation techniques. The ultimate goal is to support athletes in achieving safer and more effective recoveries, thereby reducing the likelihood of tendon reinjury.

The validity and reliability of a Japanese version of the web-based hamstring outcome score

This study aimed to translate a web-based hamstring outcome score (HaOS) questionnaire to the Japanese context. First, the validity and reliability of the translated questionnaires were examined among Japanese athletes. Second, the association between the previous history of hamstring strain and HaOS was examined. The translation was performed according to internationally recognized methodologies. A total of 233 athletes were asked to complete the HaOS questionnaire, and four questions were added to examine the content validity of the questionnaire. Intraclass correlation coefficient (ICC) was calculated to evaluate the test-retest reliability. Internal consistency was determined by calculating Cronbach's alpha values. The translated questionnaires had high acceptance and compliance rates, with a response rate of 84.4%. The ICC for each scale ranged from 0.80 to 0.93, and Cronbach's α from 0.72 to 0.96, confirming good reliability and high internal consistency. HaOS of the previous injury group (93.4 [78.9, 100]) was significantly lower than that of the healthy group (86.2 [68.1, 100]) (p < 0.05). The translated HaOS questionnaires were valid, reliable, and acceptable for monitoring hamstring conditions in Japanese athletes.

SUPER rehabilitation of hamstring strain injuries in soccer players: Delphi consensus study

INTRODUCTION

Hamstring strain injuries (HSI) are one of the most common injuries for soccer players and there is a need for new clinical-based studies on the rehabilitation of these injuries.

OBJECTIVE

This study aimed to create a consensus on physiotherapy and rehabilitation approaches used in HSI by physiotherapists with super league experience in Turkey.

METHODS

Twenty-six male physiotherapists (duration of experience in professional life, on athlete health, and in the super league: 12.84 ± 6.04 years, 12.19 ± 5.96 years, 8.71 ± 5.31 years, respectively) from different institutions participated in the study. The research was carried out in three rounds using the Delphi method.

RESULTS

Data collected using LimeSurvey and Google Forms were analyzed using the Microsoft Excel and SPSS 22 software. The response rates over the three rounds were 100%, 96%, and 96%, respectively. The 10 main items that were agreed upon in Round 1 were divided into 93 sub-items. Their numbers in the second and third Rounds were 60 and 53, respectively. At the end of Round 3, the highest consensus was on eccentric exercise, dynamic stretching, interval running, and movement-enhancing field training. All sub-items at this round were classified as SUPER (S: Soft tissue restoration techniques; U: Using supportive approaches; P: Physical fitness exercises; E: Electro-hydro-thermal methods; and R: Return to sport activities).

CONCLUSION

SUPER rehabilitation provides a new conceptual framework in terms of approaches used by clinicians in rehabilitation for athletes with HSI. Recognizing the lack of evidence for the various approaches involved, clinicians can modify their practice and researchers can explore whether these approaches are scientifically correct.

The isometric and isokinetic knee extension and flexion muscle strength profile of elite soccer players

BACKGROUND

This study aimed to further complete normative data sets for the strength profile of the thigh in soccer players by performing isometric and isokinetic measurements in a large sample per player position.

METHODS

In total, 364 soccer players were divided into subgroups according to their pitch position. All players performed isometric and isokinetic strength measurements during active competition period using an isokinetic dynamometer (System 3, Biodex®, ENRAF-NONIUS, New York, USA).

RESULTS

Isokinetic strength of m. Quadriceps was significantly (p = 0.023) higher in strikers compared to central midfielders in both the dominant (+ 9%) and the non-dominant (+ 4%) leg. No further differences were found in isometric or isokinetic strength per playing positions.

CONCLUSIONS

We have shown that strength profiles do not differ between playing positions on the field. This is valuable information for elite soccer high performance coaches and medical staffs aiming to improve daily training efficiency and rehabilitation of their players.

Semitendinosus and biceps femoris long head activity during the single leg bridge test in healthy individuals

INTRODUCTION

The single leg bridge test (SLBT) has been suggested as a clinical test to examine function, screen injury risk, and monitor the effectiveness of rehabilitation programes targeting the hamstring. This study aimed to determine the inter-day reliability and repeatability of both SLBT performance, semitendinosus (ST), and biceps femoris long head (BFlh) surface electromyography (sEMG) responses and characterise the BFlh and ST electrical activity during the SLBT performed until exhaustion in healthy individuals.

METHODS

Twelve physically active young men without previous hamstring injury were tested for the number of repetitions attained, and sEMG signal median frequency and amplitude in both ST and BFlh of each lower limb, randomly in two sessions, with a seven-day interval between sessions.

RESULTS

High reliability [ICC = 0.85] was found for the number of SLBT repetitions attained. Reliability of sEMG outcomes showed better results for ST (ICC = 0.62-0.91) than for BFlh (ICC = 0.39-0.81), and a high to very-high repeatability was found for both ST (ICC = 0.91-0.84) and BFlh (ICC = 0.91-0.85). sEMG median frequency decreased and amplitude increased for both BFlh (p ≤ 0.001) and ST (p ≤ 0.039) at the end of SLBT, suggesting localised fatigue.

CONCLUSIONS

The SLBT performed by healthy individuals until exhaustion proved to be reliable and to induce fatigue in both BFlh and ST, where the sEMG median frequency and amplitude can be measured on different days with acceptable reliability and high repeatability, suggesting its potential future use in both practical and clinical settings.

Recovery of spatio-temporal gait and functional parameters following unilateral eccentric exercise-induced muscle damage in the hamstrings

OBJECTIVES

This study aimed to analyze how spatiotemporal gait parameters, active knee extension range of motion, muscle activity, and self-perceived function change over a seven-day period in healthy individuals after exercise-induced muscle damage (EIMD) in the hamstrings.

DESIGN

Longitudinal cohort study.

METHODS

Twenty-four healthy males participated in four sessions before and after EIMD (pre-EIMD, 48 h, 96 h, and 168 h post-EIMD). A single-leg deadlift exercise was performed to provoke EIMD in the hamstrings of the dominant leg. Lower limb function perception, spatiotemporal gait parameters, active knee extension range of motion, and electromyographic (EMG) activity of the semitendinosus and biceps femoris muscles during gait and maximal isometric contraction were assessed bilaterally.

RESULTS

At 48 h, the EIMD-side showed reduced step length, active knee extension range of motion, maximal strength and EMG activity compared to baseline (P < 0.042), while increased relative EMG activity in the biceps femoris during gait (P = 0.001). At 96 h, step length and EMG activity on the EIMD-side reached similar values to those at baseline, whereas lower limb function perception and active knee extension range of motion returned to baseline state at 168 h post-EIMD. No changes over time were observed on the control-side.

CONCLUSIONS

Recovery from EIMD requires a multimodal assessment since the different parameters affected by EIMD recover at different paces. Active range of motion appears to be the last variable to fully recover. Self-perceived function should not be considered in isolation as it does not represent complete functional recovery.

[Injury prevention in football : A challenge for team doctors and coaching team]

High injury rates and long injury-related downtimes demonstrate the need for effective and differentiated injury prevention strategies in football. Preventive measures should take place in various fields and should not be reduced to training programmes or medical approaches. The so-called "Big 6 of injury prevention" provide an overview of the key areas that should be addressed. In modern sports medicine, it should be a matter of course that the team doctor already participates in the primary prevention strategies and does not only get involved in the post-traumatic treatment. Similarly, a decision on a player's return to play after an injury should not be based solely on the medical assessment of the team doctor. Good communication and interdisciplinary cooperation, therefore, form the basis for successful prevention.

The Future of Artificial Intelligence in Sports Medicine and Return to Play

Artificial intelligence (AI) has shown tremendous growth over the last decade, with the more recent development of clinical applications in health care. The ability of AI to synthesize large amounts of complex data automatically allows health care providers to access previously unavailable metrics and thus enhance and personalize patient care. These innovations include AI-assisted diagnostic tools, prediction models for each treatment pathway, and various tools for workflow optimization. The extension of AI into sports medicine is still early, but numerous AI-driven algorithms, devices, and research initiatives have delved into predicting and preventing athlete injury, aiding in injury assessment, optimizing recovery plans, monitoring rehabilitation progress, and predicting return to play.

Exploring the true burden of a time-loss injury: full vs partial time-loss in elite academy football (soccer)

In football, the number of days without full participation in training/competition is often used as a surrogate measure for time-loss (TL) caused by injury. However, injury management and return-to-play processes frequently include modified participation, which to date has only been recorded through self-reports. This study aims to demonstrate the differentiation between 'full' (no participation in team football) and 'partial' (reduced/modified participation in team football) burden. Injury and exposure data were collected from 118 male elite footballers (U13-U18) over 3 consecutive seasons according to the Football Consensus Statement. TL injury burden was calculated separately as the number of total, 'full' and 'partial' days lost per 1000 h of exposure. Injury burden (137.2 days lost/1000 h, 95% CI 133.4-141.0) was comprised of 23% (31.9 days lost/1000 h, 95% CI 30.1-33.8) partial TL and 77% (105.3 days lost/1000 h, 95% CI 102.0-108.6) full TL burden. Injuries of moderate severity (8-28 days lost) showed 40% of partial TL. TL injury incidence rate (6.6 injuries/1000 h, 95% CI 5.8-7.5), the number of severe injuries (16%), and the distribution of TL and non-TL injuries (56% and 44%) were comparable to other reports in elite youth footballers. Almost one-quarter of the TL injury burden showed that injured players were still included in some team football activities, which, for injuries with TL >7 days, was likely related to the return to play process. Therefore, reporting on partial TL provides insight into the true impact of injury on participation levels.

Effectiveness of cryo plus ultrasound therapy versus diathermy in combination with high-intensity laser therapy for pain relief in footballers with muscle injuries: A prospective study

BACKGROUND

Muscle injuries are common traumatic events in the clinical practice of the rehabilitation field. There is still a gap in the scientific literature on the effectiveness of physical agent modalities in the management of muscle injuries in athletes.

OBJECTIVE

The aim of this study was to assess the effectiveness of cryo plus ultrasound therapy com-pared to diathermy in combination with high-intensity laser therapy (HILT) for pain relief in professional footballers with muscle injuries.

METHODS

A case-control study was conducted on 31 professional footballers with a muscle injury of the lower limbs. Of these, 17 patients, assigned to a Group A (AG), were treated with HILT and cryoultrasound therapy; the remaining 14 patients, assigned to a Group B (BG), underwent HILT and diathermy. We assessed the extent of the pain, the size of the muscle injury, frequency of recurrence and number of days to recovery, at the time of recruitment, at the end of the rehabilitation and 3 months after the injury.

RESULTS

Group A athletes had a greater benefit on pain (4.65 ± 0.61 vs 3.24 ± 0.63; p< 0.05) and muscle injury recurrence. The return to play in the athletes of group A took place 4.73 days earlier.

CONCLUSION

HILT and cryo plus ultrasound therapy, in combination with therapeutic exercise, rep-resent a valid strategy in the treatment of muscle injuries in professional footballers.

Determining the definition and components of successful soccer referee performance

There has been little work examining the intricacies of what makes a soccer referee successful. The aim of this study was to determine what the definition of a successful referee performance is and what are the characteristics of a successful referee from a broad range of stakeholders in Major League Soccer (MLS) and the Professional Referees Organisation (PRO). The study used Delphi methodology to ask 6 MLS General Managers, 2 MLS Coaches,1 MLS League Officer, 4 PRO Referees and 10 PRO Assistant Referees, 8 PRO Staff and 5 PRO Assessors, and 2 PRO2 Referees two questions: 1. Their definition of a successful referee performance. 2. Their opinion on the characteristics of a successful referee. The result was a 7-point definition of a successful referee performance and 26 characteristics of a successful referee. There were ten characteristics that overlapped with previous work examining successful referees. This study was able to develop a definition of a successful referee performance and determine the characteristics of a successful referee.

Examination of the validity of the Injury-Psychological Readiness to Return to Sport (I-PRRS) scale in male professional football players: A worldwide study of 29 professional teams

Perceived confidence is an important dimension of an athlete's psychological readiness to return-to-play. However, there is no established and validated tool to evaluate confidence in professional football. This study aimed to provide preliminary evaluation of the internal structure of the Injury-Psychological Readiness to Return-to-Sport scale (I-PRRS) in a cohort of injured male professional footballers. Over an 18-month period, 29 teams from 17 leagues participated. Players sustaining injuries eliciting ≥ 3 weeks' time-loss were recruited. Cross culturally adapted to 4 further languages, the I-PRRS was administered on two occasions: 1) day before returning-to-training and 2) day before returning-to-match-play. In total, 113 injuries were recorded with 96 completed I-PRRS data sets collected. Confirmatory factor analysis indicated the I-PRRS was a unidimensional scale, with all items measuring the same construct. The scale demonstrated good internal consistency (ω = .88). When examining longitudinal invariance of the I-PRRS across administration time-points, indices of model fit supported scalar invariance. There was preliminary evidence of good internal structure for the I-PRRS in professional male footballers. However, before further research involving the I-PRRS can be endorsed, efforts to confirm or refute empirical developments pertaining to psychological readiness are necessary.

Neuromuscular electrical stimulation during maximal voluntary contraction: a Delphi survey with expert consensus

PURPOSE

The use of electrical stimulation to assess voluntary activation of muscle/s is a popular method employed in numerous exercise science and health research settings. This Delphi study aimed to collate expert opinion and provide recommendations for best practice when using electrical stimulation during maximal voluntary contractions.

METHODS

A two-round Delphi study was undertaken with 30 experts who completed a 62-item questionnaire (Round 1) comprising of open- and closed-ended questions. Consensus was assumed if ≥ 70% of experts selected the same response; such questions were removed from the subsequent Round 2 questionnaire. Responses were also removed if they failed to meet a 15% threshold. Open-ended questions were analysed and converted into closed-ended questions for Round 2. It was assumed there was no clear consensus if a question failed to achieve a ≥ 70% response in Round 2.

RESULTS

A total of 16 out of 62 (25.8%) items reached consensus. Experts agreed that electrical stimulation provides a valid assessment of voluntary activation in specific circumstances, such as during maximal contraction, and this stimulation can be applied at either the muscle or the nerve. Experts recommended using doublet stimuli, self-adhesive electrodes, a familiarisation session, real-time visual or verbal feedback during the contraction, a minimum current increase of + 20% to ensure supramaximal stimulation, and manually triggering stimuli.

CONCLUSION

The results of this Delphi consensus study can help researchers make informed decisions when considering technical parameters when designing studies involving electrical stimulation for the assessment of voluntary activation.

Development of a Standardised System to Classify Injury-Inciting Circumstances in Football: the Football Injury Inciting Circumstances Classification System (FIICCS)

BACKGROUND

A comprehensive examination of the sport-specific activities and circumstances being performed at the time of injury is important to hypothesise mechanisms, develop prevention strategies and inform future investigations. Results reported in the literature are inconsistent because inciting activities are reported using different classifications. Hence the aim was to develop a standardised system for the reporting of inciting circumstances.

METHODS

The system was developed using a modified Nominal Group Technique. The initial panel included 12 sports practitioners and researchers from four continents with respectively ≥ 5 years of experience working in professional football and/or conducting injury research. The process consisted of six phases: idea generation, two surveys, one online meeting and two confirmations. For answers to the closed questions, consensus was deemed achieved if ≥ 70% of respondents agreed. Open-ended answers were qualitatively analysed and then introduced in subsequent phases.

RESULTS

Ten panellists completed the study. The risk of attrition bias was low. The developed system includes a comprehensive range of inciting circumstances across five domains: contact type, ball situation, physical activity, session details, contextual information. The system also distinguishes between a core set (essential reporting) and an optional set. The panel deemed all the domains to be important and easy to use both in football and in research environments.

CONCLUSION

A system to classify inciting circumstances in football was developed. Given the extent of reporting inconsistency of inciting circumstances in the available literature, this can be used while further studies evaluate its reliability.

Establishing internationally accepted conceptual and operational definitions of social prescribing through expert consensus: a Delphi study

OBJECTIVE

The aim of this study was to establish internationally accepted conceptual and operational definitions of social prescribing.

DESIGN

A three-round Delphi study was conducted.

SETTING

This study was conducted virtually using an online survey platform.

PARTICIPANTS

This study involved an international, multidisciplinary panel of experts. The expert panel (n=48) represented 26 countries across five continents, numerous expert groups and a variety of years of experience with social prescribing, with the average being 5 years (range=1-20 years).

RESULTS

After three rounds, internationally accepted conceptual and operational definitions of social prescribing were established. The definitions were transformed into the Common Understanding of Social Prescribing (CUSP) conceptual framework.

CONCLUSION

This foundational work offers a common thread-a shared sense of what social prescribing is, which may be woven into social prescribing research, policy and practice to foster common understanding of this concept.

How are hamstring strain injuries managed in elite men's football clubs? A survey with 62 Brazilian physical therapists

OBJECTIVE

To describe perceptions and practices of physical therapists from elite men's football clubs on the management of athletes with hamstring strain injury (HSI).

DESIGN

Cross-sectional study.

SETTING

Online survey.

PARTICIPANTS

Physical therapists from clubs engaged in the two main divisions of Brazilian men's football.

MAIN OUTCOME MEASURES

Practices for assessment and rehabilitation of athletes with HSI.

RESULTS

This survey had 62 physical therapists from 35 of the 40 eligible clubs (87.5% representativeness). Despite heterogeneity on assessment practices, all respondents use imaging exams, adopt injury classification scales, and evaluate aspects related to pain, range of motion, muscle strength, and functional status of athletes with HSI. Rehabilitation programs are usually divided into 3 to 4 phases. All respondents usually apply electrophysical agents and stretching in HSI rehabilitation programs, 98.4% apply strengthening exercises (93.5% include eccentrics), 96.8% manual therapy, 95.2% exercises that mimic the functional demands of football, and 93.5% lumbopelvic stabilization exercises. Muscle strength was the most reported return to play criterion (71% of respondents).

CONCLUSION

The present study allowed the sports physical therapy community to become aware of the approaches usually adopted for management of athletes with HSI who play in the highest level of Brazilian men's football.

London International Consensus and Delphi study on hamstring injuries part 1: classification

Muscle injury classification systems for hamstring injuries have evolved to use anatomy and imaging information to aid management and prognosis. However, classification systems lack reliability and validity data and are not specific to individual hamstring muscles, potentially missing parameters vital for sport-specific and activity-specific decision making. A narrative evidence review was conducted followed by a modified Delphi study to build an international consensus on best-practice decision-making for the classification of hamstring injuries. This comprised a digital information gathering survey to a cohort of 46 international hamstring experts (sports medicine physicians, physiotherapists, surgeons, trainers and sports scientists) who were also invited to a face-to-face consensus group meeting in London . Fifteen of these expert clinicians attended to synthesise and refine statements around the management of hamstring injury. A second digital survey was sent to a wider group of 112 international experts. Acceptance was set at 70% agreement. Rounds 1 and 2 survey response rates were 35/46 (76%) and 99/112 (88.4%) of experts responding. Most commonly, experts used the British Athletics Muscle Injury Classification (BAMIC) (58%), Munich (12%) and Barcelona (6%) classification systems for hamstring injury. Issues identified to advance imaging classifications systems include: detailing individual hamstring muscles, establishing optimal use of imaging in diagnosis and classification, and testing the validity and reliability of classification systems. The most used hamstring injury classification system is the BAMIC. This consensus panel recommends hamstring injury classification systems evolve to integrate imaging and clinical parameters around: individual muscles, injury mechanism, sporting demand, functional criteria and patient-reported outcome measures. More research is needed on surgical referral and effectiveness criteria, and validity and reliability of classification systems to guide management.

London International Consensus and Delphi study on hamstring injuries part 3: rehabilitation, running and return to sport

Hamstring injuries (HSIs) are the most common athletic injury in running and pivoting sports, but despite large amounts of research, injury rates have not declined in the last 2 decades. HSI often recur and many areas are lacking evidence and guidance for optimal rehabilitation. This study aimed to develop an international expert consensus for the management of HSI. A modified Delphi methodology and consensus process was used with an international expert panel, involving two rounds of online questionnaires and an intermediate round involving a consensus meeting. The initial information gathering round questionnaire was sent to 46 international experts, which comprised open-ended questions covering decision-making domains in HSI. Thematic analysis of responses outlined key domains, which were evaluated by a smaller international subgroup (n=15), comprising clinical academic sports medicine physicians, physiotherapists and orthopaedic surgeons in a consensus meeting. After group discussion around each domain, a series of consensus statements were prepared, debated and refined. A round 2 questionnaire was sent to 112 international hamstring experts to vote on these statements and determine level of agreement. Consensus threshold was set a priori at 70%. Expert response rates were 35/46 (76%) (first round), 15/35 (attendees/invitees to meeting day) and 99/112 (88.2%) for final survey round. Statements on rehabilitation reaching consensus centred around: exercise selection and dosage (78.8%-96.3% agreement), impact of the kinetic chain (95%), criteria to progress exercise (73%-92.7%), running and sprinting (83%-100%) in rehabilitation and criteria for return to sport (RTS) (78.3%-98.3%). Benchmarks for flexibility (40%) and strength (66.1%) and adjuncts to rehabilitation (68.9%) did not reach agreement. This consensus panel recommends individualised rehabilitation based on the athlete, sporting demands, involved muscle(s) and injury type and severity (89.8%). Early-stage rehab should avoid high strain loads and rates. Loading is important but with less consensus on optimum progression and dosage. This panel recommends rehabilitation progress based on capacity and symptoms, with pain thresholds dependent on activity, except pain-free criteria supported for sprinting (85.5%). Experts focus on the demands and capacity required for match play when deciding the rehabilitation end goal and timing of RTS (89.8%). The expert panellists in this study followed evidence on aspects of rehabilitation after HSI, suggesting rehabilitation prescription should be individualised, but clarified areas where evidence was lacking. Additional research is required to determine the optimal load dose, timing and criteria for HSI rehabilitation and the monitoring and testing metrics to determine safe rapid progression in rehabilitation and safe RTS. Further research would benefit optimising: prescription of running and sprinting, the application of adjuncts in rehabilitation and treatment of kinetic chain HSI factors.

London International Consensus and Delphi study on hamstring injuries part 2: operative management

The key indications for surgical repair of hamstring injuries (HSIs) remain unclear in the literature due to a lack of high-level evidence and expert knowledge. The 2020 London International Hamstring Consensus meeting aimed to highlight clear surgical indications and to create a foundation for future research. A literature review was conducted followed by a modified Delphi process, with an international expert panel. Purposive sampling was used with two rounds of online questionnaires and an intermediate round involving a consensus meeting. The initial information gathering (round 1) questionnaire was sent to 46 international experts, which comprised open-ended questions covering decision-making domains in HSI. Thematic analysis of responses outlined key domains, which were evaluated by a smaller international subgroup (n=15) comprising clinical academic sports medicine physicians, physiotherapists and orthopaedic surgeons in a consensus meeting. After group discussion of each domain, a series of consensus statements were prepared, debated and refined. A round 2 questionnaire was sent to 112 international hamstring experts to vote on these statements and determine level of agreement. The consensus threshold was set a priori at 70% agreement. Rounds 1 and 2 survey respondents were 35/46 (76%) and 99/112 (88.4%), respectively. The consensus group agreed that the indications for operative intervention included: gapping at the zone of tendinous injury (87.2% agreement) and loss of tension (70.7%); symptomatic displaced bony avulsions (72.8%); and proximal free tendon injuries with functional compromise refractory to non-operative treatment (72.2%). Other important considerations for operative intervention included: the demands of the athlete/patient and the expected functional outcome (87.1%) based on the anatomy of the injury; the risk of functional loss/performance deficit with non-operative management (72.2%); and the capacity to restore anatomy and function (87.1%). Further research is needed to determine whether surgery can reduce the risk of reinjury as consensus was not reached within the whole group (48.2%) but was agreed by surgeons (70%) in the cohort. The consensus group did not support the use of corticosteroids or endoscopic surgery without further evidence. These guidelines will help standardise treatment of HSIs, specifically the indications and decision-making for surgical intervention.

The Effects of Fixture Congestion on Injury in Professional Male Soccer: A Systematic Review

BACKGROUND

Professional soccer teams are often required to compete with ≤ 4 days recovery between matches. Since congested schedules reduce recovery time between matches, players are possibly at an increased injury risk. To date, there are no published systematic reviews on the impact of match congestion on injuries during professional male soccer.

OBJECTIVE

The aim of this systematic review was to assess the effects of fixture congestion on injuries during professional soccer.

METHODS

Following pre-registration on the Open Science Framework ( https://osf.io/86m25/ ) and conforming with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, systematic searches of four electronic databases (PubMed, Scopus, SPORTDiscus, and Web of Science) were conducted by independent researchers from inception until February 2022. Articles were included if they were original articles written in English and contained relevant time-loss injury data (injury that results in unavailability for training and/or match-play) for male professional soccer players regarding periods of fixture congestion (a minimum of two matches with ≤ 4 days recovery).

RESULTS

A total of eight articles were included in the review. Five studies identified that congested fixture schedules expose players to increased match injury incidence, although layoff duration was typically lower during congested periods. Two studies identified that training and overall injury incidence were higher during congested periods, with another study identifying a lower training injury incidence during congested periods.

CONCLUSION

Injury risk is, overall, increased during fixture-congested periods; however, the layoff duration is typically shorter. The current findings have implications for practitioners regarding the management, periodisation, monitoring, and design of training and competition schedules.

Pain and Psychological Readiness to Return to Sport in Elite Volleyball Players: A Cross-Sectional Study

Pain is modulated by multiple factors. A relevant psychological process peculiar to athletes and which could be associated with pain is Psychological Readiness to Return to Sport (PRRS). The analysis of this association in competition context is particularly important.

OBJECTIVE

To determine the correlation between the PRRS and pain intensity in elite volleyball players during their participation in a continental sporting event.

METHODS

A cross-sectional study was conducted. Data from 107 male volleyball players (23.50 ± 4.08 years of age) participating in the South American Volleyball Championship were used. The athletes answered a self-report questionnaire on the day the championship began regarding their history of injuries in the previous six months. The athletes who declared injuries were asked about the current pain intensity using the Pain Numeric Rating Scale (NRS) and Psychological Readiness to Return to Sport using the Injury-Psychological Readiness to Return to Sport scale (I-PRRS).

RESULTS

43.93% (n = 47) of the athletes (23.70 ± 3.54 years) reported an injury in the six months prior to the championship. They presented a median on the NRS of three (interquartile range (IQR), 2-5), and 54 (IQR, 46-58) on the I-PRRS. The Spearman's Rho correlation test showed an inversely and moderate correlation (r_s = -0.36; p = 0.011; CI: -0.64--0.08) between pain intensity and PRRS.

CONCLUSIONS

In male elite volleyball players who participate in a Continental Championship in South America, higher levels of PRRS was correlated to lower pain intensity.

Establishing Internationally Accepted Conceptual and Operational Definitions of Social Prescribing Through Expert Consensus: A Delphi Study Protocol

Introduction

There is currently no agreed definition of social prescribing. This is problematic for research, policy, and practice, as the use of common language is the crux of establishing a common understanding. Both conceptual and operational definitions of social prescribing are needed to address this gap. Therefore, the aim of the study that is outlined in this protocol is to establish internationally accepted conceptual and operational definitions of social prescribing.

Methodology

A Delphi study will be conducted to develop internationally accepted conceptual and operational definitions of social prescribing with an international, multidisciplinary panel of experts. It is anticipated that this study will involve approximately 40 participants (range = 20-60 participants) and consist of 3-5 rounds. Consensus will be defined a priori as ≥80% agreement.

Discussion

Not only will these definitions serve to unite the social prescribing community, but they will also inform research, policy, and practice. By laying the groundwork for the formation of a robust evidence base, this foundational work will support the advancement of social prescribing and help to unlock the full potential of the social prescribing movement.

Conclusion

This important work will be foundational and timely, given the rapid spread of the social prescribing movement around the world.

Defining and quantifying fatigue in the rugby codes

The rugby codes (i.e., rugby union, rugby league, rugby sevens [termed 'rugby']) are team-sports that impose multiple complex physical, perceptual, and technical demands on players which leads to substantial player fatigue post-match. In the post-match period, fatigue manifests through multiple domains and negatively influences recovery. There is, however, currently no definition of fatigue contextualised to the unique characteristics of rugby (e.g., locomotor and collision loads). Similarly, the methods and metrics which practitioners consider when quantifying the components of post-match fatigue and subsequent recovery are not known. The aims of this study were to develop a definition of fatigue in rugby, to determine agreement with this common definition of fatigue, and to outline which methods and metrics are considered important and feasible to implement to quantify post-match fatigue. Subject matter experts (SME) undertook a two-round online Delphi questionnaire (round one; n = 42, round two; n = 23). SME responses in round one were analysed to derive a definition of fatigue, which after discussion and agreement by the investigators, obtained 96% agreement in round two. The SME agreed that fatigue in rugby refers to a reduction in performance-related task ability which is underpinned by time-dependent negative changes within and between cognitive, neuromuscular, perceptual, physiological, emotional, and technical/tactical domains. Further, there were 33 items in the neuromuscular performance, cardio-autonomic, or self-report domains achieved consensus for importance and/or feasibility to implement. Highly rated methods and metrics included countermovement jump force/power (neuromuscular performance), heart rate variability (cardio-autonomic measures), and soreness, mood, stress, and sleep quality (self-reported assessments). A monitoring system including highly-rated fatigue monitoring objective and subjective methods and metrics in rugby is presented. Practical recommendations of objective and subjective measures, and broader considerations for testing and analysing the resulting data in relation to monitoring fatigue are provided.

Readaptación deportiva y retorno deportivo en el alto rendimiento. Del laboratorio al campo de juego: Una revisión de la literatura

Introducción En la actualidad, la readaptación deportiva se conoce como un proceso dinámico a nivel estructural y funcional de elementos del movimiento corporal humano tales como la caracterización de cualidades físicas, sinergias articulares y musculares, eficiencia y eficacia del movimiento y potencialización de habilidades funcionales para el deporte de alto rendimiento después de una lesión deportiva Metodología revisión de la literatura basados en los criterios PRISMA donde se hizo la búsqueda en las principales bases de datos tales como: Pubmed, Ebsco, Medline, Scopus, Science Direct con los siguientes terminos DeCS: Return to sport, Performance, sports, Return to training, Return to play, Rehabilitation, sports idioma de evidencia inglés, español, portugués, catalán y francés Resultados se pudo obtener la información de 74 artículos donde se estableció que el proceso de readaptación deportiva se basa en pilares específicos tales como movimiento, patrones funcionales, control de carga, monitorización, criterios de seguimiento por fase que permiten desarrollar un retorno exitoso al alto rendimiento deportivo. Conclusión la readaptación deportiva es un proceso que permite tomar decisiones basados en un proceso sistematizado generando la evolución del concepto de readaptador deportivo como un pilar esencial en el trabajo en el deporte de alto rendimiento en cualquier disciplina deportiva.   PALABRAS CLAVE: Return to Sport, Performance, sports, Return to training, Return to play

MRI findings prior to return to play as predictors of reinjury in professional athletes: a novel decision-making tool

BACKGROUND

Because MRI has shown great accuracy in assessing acute muscle injuries, identification of risk factors for reinjury before return to play (RTP) in professional athletes during the healing process could be very relevant. We assessed the value of MRI findings prior to RTP as predictors of reinjury.

METHODS

Retrospective observational study of 59 professional athletes, mean age 26 years, with first-time acute muscle injury and successful rehabilitation ready to RTP. They underwent MRI within 6 days of the injury and within 7 days prior to RTP. The primary outcome was reinjury. Risk of reinjury was assessed using radiological signs in control MRI scans before RTP. The risk was classified as low, medium or high when none, one or two radiological signs were observed, respectively.

RESULTS

Reinjury occurred in 9 participants, with a rate of 15.2%. None of the baseline MRI-related variables was significantly associated with reinjury. In the control MRI scan performed within 7 days prior to RTP, three independent findings were significantly associated with reinjury. These included transversal and/or mixed connective tissue gap (p = 0.002), intermuscular oedema (p = 0.015) and callus gap (p = 0.046). In the predictive model of the risk of reinjury, the presence of two of these radiological signs, together with interstitial feathery oedema, was associated with a high risk of recurrence (OR 29.58, 95% CI 3.86-226.64; p = 0.001).

CONCLUSIONS

In professional athletes with acute muscle injuries of the lower limbs successfully rehabilitated, some radiological signs on MRI performed shortly before RTP were associated with a high risk of reinjury.

Return to Play in Long-Standing Adductor-Related Groin Pain: A Delphi Study Among Experts

Background

Groin pain is a very common injury in multidirectional sports such as soccer, ice hockey, rugby and Australian football. Long-standing adductor-related groin pain is a persistent clinical condition and a frequent complaint in athletes involved in sports that require multiplanar movement patterns (change of direction, high-speed sprinting and kicking). To date, the lack of rehabilitation guidelines and return-to-play criteria makes this clinical entity difficult to manage. The aim of the present Delphi was to suggest, based on opinion and practical experience of a panel of experts, potential criteria that could be taken into consideration by clinicians in the RTP decision-making process in athletes suffering from long-standing adductor-related groin pain.

Methods

Thirty two out of 40 experts participated to a 3-Round Delphi questionnaire. In round 1, open-ended and closed questions about 9 different sections (palpation, flexibility, strength, patient-reported outcome measures, imaging, intersegmental control, performance tests, sport-specific skills, training load) were proposed to investigate return to play evaluation criteria used by each expert. Responses were analysed and coded to produce round 2 questionnaire that investigated only the sections and the items that reached the cut-off value (≥ 70%). Round 3 questionnaire was based on sections and items that reached cut-off value in previous rounds and experts rated their agreement for return to play criteria with a 5-point Likert Scale. Descriptive statistics enabled interpretation of consensus.

Results

High participation rate (80%) and response rate across the 3 rounds (100%) were recorded. 6 sections reached positive consensus in round 1, 1 section reached negative consensus. In round 2 positive consensus was confirmed only for 3 sections and negative consensus for 1 section. In round 3, positive agreement was established for strength (3 items), performance tests (3 items) and sport-specific skills (2 items) sections. Negative consensus was confirmed for imaging section.

Conclusion

Experts agreed that strength, performance tests and sport-specific skills can be used to support RTP decision, while imaging cannot be used. These findings could be useful in assisting clinicians in the RTP decision making.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-021-00400-z.

Contributors to negative biopsychosocial health or performance outcomes in rugby players (CoNBO): a systematic review and Delphi study protocol

The importance of contributors that can result in negative player outcomes in sport and the feasibility and barriers to modifying these to optimise player health and well-being have yet to be established. Within rugby codes (rugby league, rugby union and rugby sevens), within male and female cohorts across playing levels (full-time senior, part-time senior, age grade), this project aims to develop a consensus on contributors to negative biopsychosocial outcomes in rugby players (known as the CoNBO study) and establish stakeholder perceived importance of the identified contributors and barriers to their management. This project will consist of three parts; part 1: a systematic review, part 2: a three-round expert Delphi study and part 3: stakeholder rating of feasibility and barriers to management. Within part 1, systematic searches of electronic databases (PubMed, Scopus, MEDLINE, SPORTDiscus, CINAHL) will be performed. The systematic review protocol is registered with PROSPERO. Studies will be searched to identify physical, psychological and/or social factors resulting in negative player outcomes in rugby. Part 2 will consist of a three-round expert Delphi consensus study to establish additional physical, psychological and/or social factors that result in negative player outcomes in rugby and their importance. In part 3, stakeholders (eg, coaches, chief executive officers and players) will provide perceptions of the feasibility and barriers to modifying the identified factors within their setting. On completion, several manuscripts will be submitted for publication in peer-reviewed journals. The findings of this project have worldwide relevance for stakeholders in the rugby codes. PROSPERO registration number CRD42022346751.

Psychological readiness to return to sports practice and risk of recurrence: Case studies

Returning to sport after the sports injury is a difficult decision because it's multicausal and the fact that a rash decision can result in numerous negative consequences. Given the importance of psychological variables for the correct rehabilitation of the injured athlete and his or her optimal return to sports practice, there seems to be little information on this subject. In this sense, the objective is to determine the relationship between the subjective psychological disposition of the athlete in the process of Return to Play (RTP) with the type of mood profile and his mental health. This is based on the fact that each athlete evaluates his or her recovery differently and has different levels of anxiety, depression, and stress. For this purpose, four athletes participated in the study. Two males and two females from the sports of indoor soccer and soccer, who had just returned to sports after a moderate or severe injury. The average age was 24.25 years. Various measurements were taken after practices and after matches, to assess mood, psychological readiness, anxiety, stress, and depression. The results confirm Morgan's iceberg profile and the influence that subjective psychological perceptions and assessed emotional states have on athletes' incorporation into their sports practice with a guarantee of success.

Sport-Specific Rehabilitation, but Not PRP Injections, Might Reduce the Re-Injury Rate of Muscle Injuries in Professional Soccer Players: A Retrospective Cohort Study

Platelet-rich plasma (PRP) injections are extremely popular in the management of sports injuries in elite athletes. However, data on the use of various administration protocols of PRP are contradictory. The efficacy of platelet-rich plasma in the treatment of muscle injuries in professional soccer players has to be contextualized within the sport-specific rehabilitation program. Despite the questionable role of PRP, a well-structured rehabilitation program is still regarded as the gold standard. We examined the efficacy of various PRP protocols in the management of muscle injuries in professional soccer players in respect to treatment duration and injury recurrence. A retrospective cohort study. Muscle injuries in professional soccer players (n = 79, height 182.1 ± 5.9 cm, weight 76.8 ± 5.8 kg, BMI 23.1 ± 1.4 kg/m2) from three elite soccer clubs from the Russian Premier League were recorded during the 2018−2019 season. The injuries were graded based on MRI, using the British Athletic Muscle Injury Classification. Treatment protocols included the POLICE regimen, short courses of NSAID administration, and the specific rehabilitation program. The sample group of players were administered PRP injections. The average treatment duration with PRP injection was significantly longer than conventional treatment without PRP, 21.5 ± 15.7 days and 15.3 ± 11.1 days, respectively (p = 0.003). Soccer-specific rehabilitation and obtaining MRI/US before the treatment was associated with significantly reduced injury recurrence rate (p < 0.001). There was no significant difference between the PRP injection protocol applied to any muscle and the treatment duration in respect of grade 2A−2B muscle injuries. The total duration of treatment of type 2A−2B injuries was 15 days among all players. In the group receiving local injections of PRP, the total duration of treatment was 18 days; in the group without PRP injections, the treatment duration was 14 days. In our study, PRP treatment was associated with longer treatment duration, regardless of which muscle was injured. This may reflect the tendency to use PRP in higher-degree injuries. Soccer-specific rehabilitation significantly reduced the injury recurrence rate when compared to the administration of PRP injections. MRI/US imaging before returning to play was also associated with a lower injury recurrence rate. There was no significant difference between the PRP injection protocol applied to any muscle and the treatment duration in treatment of type 2A−2B muscle injuries.

Data Collection Procedures and Injury Definitions in Badminton: A Consensus Statement According to the Delphi Approach

ABSTRACT

Previous studies involving injury surveillance in badminton players have used nonstandardized injury definitions and data collection methodologies. The purpose of this study was to apply a Delphi method to (1) reach a consensus on an injury definition in badminton and (2) develop a standardized badminton injury report form. An Injury Consensus Group was established under the auspices of the Badminton World Federation, and initial injury definitions and injury report form were developed. An internal panel was formed from the Injury Consensus Group, and an external panel was selected based on a combination of profession, experience in the field, sport-specific knowledge/expertise, and geographical location to obtain a widely representative sample. Through 2 rounds of voting by the external panel, consensus was reached on both the definition of an injury in badminton and a standardized injury report form. The agreed injury definition was "Any physical injury sustained by a player during a match or training regardless if further diagnostic tests were done or if playing time was lost" and the injury report form contained the following 7 sections: Injury record, Diagnosis, Injury mechanism, Regarding pain, Pain and return to play/training after injury, Grade of severity, and Recurrence. We recommend the use of the definitions and methods presented in this consensus statement for the reporting of injury in all international and domestic badminton players. This should make future injury surveillance reports directly comparable and hence more informative in recognizing trends over time and differences between countries.

Applied sports science and sports medicine in women's rugby: systematic scoping review and Delphi study to establish future research priorities

Objectives

In part 1, the objective was to undertake a systematic scoping review of applied sports science and sports medicine in women's rugby, and in part 2 to develop a consensus statement on future research priorities.

Design

In part 1, a systematic search of PubMed (MEDLINE), Scopus and SPORTDiscus (EBSCOhost) was undertaken from the earliest records to January 2021. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020, the PRISMA extension for Scoping Reviews, and the PRISMA extension protocols were followed. In part 2, 31 international experts in women's rugby (ie, elite players, sports scientists, medical clinicians, sports administrators) participated in a three-round Delphi consensus method. These experts reviewed the findings from part 1 and subsequently provided a list of priority research topics in women's rugby. Research topics were grouped into expert-based themes and expert-based subthemes via content analysis. Expert-based themes and expert-based subthemes were ranked from very low to very high research priority on a 1-5 Likert scale. Consensus was defined by ≥70% agreement. The median research priority agreement and IQR were calculated for each expert-based theme and subtheme.

Data sources

PubMed (MEDLINE), Scopus and SPORTDiscus (EBSCOhost).

Eligibility criteria for selecting studies

Studies were eligible for inclusion if they investigated applied sports science or sports medicine in women's rugby.

Results

In part 1, the systematic scoping review identified 123 studies, which were categorised into six sports science and sports medicine evidence-based themes: injury (n=48), physical performance (n=32), match characteristics (n=26), fatigue and recovery (n=6), nutrition (n=6), and psychology (n=5). In part 2, the Delphi method resulted in three expert-based themes achieving consensus on future research priority in women's rugby: injury (5.0 (1.0)), female health (4.0 (1.0)) and physical performance (4.0 (1.0)).

Summary/Conclusion

This two-part systematic scoping review and Delphi consensus is the first study to summarise the applied sports science and sports medicine evidence base in women's rugby and establish future research priorities. The summary tables from part 1 provide valuable reference information for researchers and practitioners. The three expert-based themes that achieved consensus in part 2 (injury, female health and physical performance) provide clear direction and guidance on future research priorities in women's rugby. The findings of this two-part study facilitate efficient and coordinated use of scientific resources towards high-priority research themes relevant to a wide range of stakeholders in women's rugby.

Monitorización y periodización del rendimiento desde la fisioterapia deportiva ¿Hacia dónde vamos?

RESUMEN Introducción El concepto de monitorización y periodización es un visión que se ha desarrollado en la última década, donde se busca que se pueda tener un control de la carga interna y externa en los deportistas de distintas disciplinas deportivas producidas por el proceso de interacción con variables de prescripción de ejercicio que causan modificaciones a nivel fisiológico, bioquímico, biomecanico, muscular, neuromuscular  ocasionando la tensión en los subsistemas del movimiento corporal humano generando adaptaciones especificas ante una carga determinada la cual puede ser medida mediante el uso de tecnología especifica o test indirectos Metodología Revisión de la literatura con la combinación de palabras clave como Monitoring, Performance, sports training load, Periodization en bases de datos como Pubmed, Ebsco, Medline, Scopus, Science Direct Resultados se pudo identificar 65 artículos que referencian la existencia  de herramientas tecnológicas para realizar un proceso de monitorización y periodización desde la rehabilitación , prevención, control de carga, recuperación y readaptación deportiva que permiten la generación de datos estadísticos y crear perfiles desde cada área de actuación del fisioterapeuta deportivo. Conclusión la fisioterapia es una profesión encargada de muchos procesos deportivos que deben ser monitorizados y generen datos que permitan estandarizar procesos, crear perfiles de seguimiento específicos para facilitar la toma de decisiones desde el equipo biomédico e investigaciones en el deporte de alto rendimiento fusionando la practica con la evidencia científica.

Injury risk factors and barriers to their mitigation for women playing rugby league: a Delphi study

This study aimed to 1) develop a consensus (≥70% agreement between experts) on injury risk factors specific to women playing rugby league, 2) establish the importance of the identified injury risk factors and the feasibility of mitigating these risk factors and 3) establish context specific barriers to injury risk management. Aim 1: A Delphi panel, consisting of 12 experts in rugby league and injury (e.g., physiotherapists, research scientists) were asked to identify injury risk factors specific to women playing rugby league. Aim 2: seven coaches of women's rugby league teams were asked to rate each risk factor that achieved consensus by their importance and feasibility to manage. Aim 3: Coaches reported barriers which restrict injury risk factor mitigation. Of the 53 injury risk factors which achieved consensus, the five injury risk factors with the highest combination of importance and feasibility ratings were: "poor tackle technique", "a lack of pre-season intensity", "training session are too short", "the current medical standards", and "limited access to physiotherapists". Following the identification of injury risk factors, their feasibility to manage and context specific barriers, this study proposes three constraint driven, integrated solutions which may reduce the barriers which limit injury risk factor management.

A Multidisciplinary Approach to Game Day Preparation for Team Sports: A Delphi Study With Expert Consensus

ABSTRACT

Mason, BRJ, Pumpa, KL, McKune, AJ, Gill, ND, and Ball, NB. A multidisciplinary approach to game day preparation for team sports: A Delphi study with expert consensus. J Strength Cond Res 36(5): 1345-1352, 2022-The aim of this study was to identify game day preparation strategies used by performance staff to improve team sport performance and to determine consensus regarding the application and importance of these strategies. Twenty-five performance staff working in high performance or professional team sports participated in this Delphi study, which implemented 3 survey rounds. The first round sought responses to open-ended questions relating to the use of game day preparation strategies. These responses were developed into statements and recirculated (round-2 survey), with subjects asked to rate their level of agreement with each statement. The third and final survey presented revised versions of statements that did not reach a consensus in the previous round, along with new statements derived from subject responses. A thematic analysis of the open-ended responses in the first survey identified 5 key themes relating to game day preparation strategies: "exercise," "nutrition," "psychological," "technical and tactical," and "other." The round-2 survey included 38 statements across the 5 themes, with 22 reaching the consensus threshold (≥75%) for agreement. The remaining 16 statements did not reach consensus. The final survey included 18 statements (16 revised and 2 new) with 12 reaching the consensus threshold for agreement. Key preparation strategies identified in this study include structured and progressive warm-ups, strength and power-based priming sessions, individualized nutrition plans, and precooling in hot conditions. Performance staff working in similar environments should consider adopting these strategies to improve athlete or team performance.

Hamstrings injuries in football

Background

Hamstrings injuries are a major concern in football (soccer), affecting both recreational players and professional athletes. Although being a recognized issue within the football community, its incidence has been increasing over the last years and still poses a challenge to all practitioners involved.

Study objectives and rationale

The goal of this narrative review is to outline hamstrings injuries epidemiology and mechanisms of injury, identify and discuss its risk factors, provide an approach to a proper early diagnosis, evaluate the efficacy of current treatment options and return to sports, and present the best strategies for hamstrings injury prevention. These guidelines will help the sports medicine staff team on how to better manage their players with or at risk of hamstrings injuries.

Conclusion

Despite several breakthroughs in research of hamstrings injuries, there is still heterogeneity across studies and lack of consensus in regards to classification, diagnosis, treatment and prevention. Hamstrings injuries compromise the athlete's performance with time loss due to injury, shortens their highest-level career longevity with higher risk of reinjury rates, and is a defying problem for clubs to balance financial losses due to having their players off the pitch. Further research is warranted to keep moving forward with evidence on treating and preventing hamstrings injuries to mitigate its high incidence and keep the players safe.

Return to match running performance after a hamstring injury in elite football: a single-centre retrospective cohort study

Objectives

To determine the number of matches to return to pre-injury match running performance after sustaining an acute hamstring injury.

Methods

In this retrospective cohort study, the injuries of the players of the first, Under21, Under19, Under18 and Under17 teams of a professional football club in the period 2017-2020 were analysed. Acute hamstring injuries with a minimal absence from training or match play of 7 days were included. For running performance, we assessed the following variables: maximal velocity (km/hour), total distance, high-intensity distance (17.5-22.5 km/hour) and sprint distance (>22.5 km/hour). We calculated the average and 95% CI for these variables during the last five matches before the injury. The primary outcome was the number of matches to reach maximal velocity within the 95% CI of the player's individual pre-injury performance. Secondary outcome scores included the duration (in days and matches) to reach the other running performance variables.

Results

18 hamstring injuries in 15 players were included. 15 out of 18 injuries (83%) showed a return to pre-injury maximal velocity in the second match after return to play. The median number of matches to return to pre-injury maximal velocity was 2 (IQR 1-2). In the first match after return to play, pre-injury total distance was reached in 100% of the injuries, pre-injury sprint distance was reached in 94% of the injuries and pre-injury high-intensity distance was reached in 89% of the injuries.

Conclusion

Following an acute hamstring injury in elite football, pre-injury match running performance is reached in the first or second match.