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Table of Contents
ORIGINAL ARTICLE
Year : 2019  |  Volume : 9  |  Issue : 1  |  Page : 35-42

Timing of musculoskeletal injuries during a single athletic event: A systematic review


1 Michael Krzyzewski Human Performance Laboratory, James R. Urbaniak Sport Science Institute, Durham, NC, USA
2 Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburg, PA, USA
3 Medical Center Library, Duke University School of Medicine, Durham, NC, USA

Date of Submission12-Sep-2019
Date of Acceptance16-Sep-2019
Date of Web Publication28-Feb-2020

Correspondence Address:
Hannah Palmer
M.S., Box 3000, Duke University Medical Center, Durham, NC 27710
USA
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/DORJ.DORJ_9_19

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  Abstract 


Aim: The aim of the study is to examine the relationship between musculoskeletal injury and time within an athletic event and to propose that these injuries may be fatigue-related.
Background: Musculoskeletal injuries impede athletic performance. The identification of risk factors is essential to reducing injury.
Materials and Methods: We searched PubMed, Embase, SPORTDiscus, and CINAHL and performed manual reference checks. Included articles reported the timing of acute musculoskeletal injury in a single athletic event; 23 articles were selected for multireviewer assessment of quality and levels of evidence.
Results: Eighty-seven percent of studies found a higher incidence of injury in later stages of play (second half or later in the second half) and 60% found this to be significant. All but two articles suggested that injury trends were related to fatigue development.
Conclusion: Based on our review, a connection between the development of musculoskeletal injury and duration of play supports the concept that fatigue is a risk factor for injury.
Clinical Significance: A greater understanding of the correlation between fatigue and musculoskeletal injury is essential to designing injury prevention programs that will decrease the onset of musculoskeletal injury in athletes. Ultimately, preventative strategies that reduce injury risk will lead to superior health and performance in athletes during athletic careers and later in life.

Keywords: Fatigue, injury prevention, sport, systematic review


How to cite this article:
Palmer H, Sell T, Killelea C, Allison K, Ledbetter L. Timing of musculoskeletal injuries during a single athletic event: A systematic review. Duke Orthop J 2019;9:35-42

How to cite this URL:
Palmer H, Sell T, Killelea C, Allison K, Ledbetter L. Timing of musculoskeletal injuries during a single athletic event: A systematic review. Duke Orthop J [serial online] 2019 [cited 2020 Oct 24];9:35-42. Available from: https://www.dukeorthojournal.com/text.asp?2019/9/1/35/279436




  Introduction Top


Musculoskeletal injury can significantly impact the athlete, affecting athletic career goals as well as overall physical health later in life.[1],[2] Therefore, understanding and reducing risk of musculoskeletal injuries is crucial to athletes, coaches, and medical professionals due to the high prevalence among the athletic population. In a sports-related injury surveillance study of US high school athletes, the nationally estimated number of injuries totaled 1,393,566 in the 2015–2016 academic year.[3] Another report found that out of 2.8 million injuries reported annually in emergency departments from individual sporting events, 64% were musculoskeletal injuries.[4] Consequently, for several decades, researchers have worked to develop more in-depth understanding of mechanisms of injury and other factors leading to musculoskeletal injury as a step toward prevention.[4],[5]

Injury prevention models have suggested that intrinsic factors (age, flexibility, previous injury, or somatotype) and exposure to external risk factors (equipment type, weather conditions, or playing surface) can lead to increased susceptibility to injury.[6] One of the latest injury prevention models, put forth by Windt and Gabbett,[7] suggests that application of extrinsic factors can either lead to fatigue or fitness. A fatiguing effect can lead to changes in modifiable intrinsic risk factors (aerobic capacity, strength, neuromuscular control, or tissue resilience). Changes in internal and external risk factors in combination with a causal or inciting event (tackle, pitch, or sprint) can lead to development of musculoskeletal injury.[6]

Musculoskeletal injuries continue to be a significant problem during athletic performance and the identification of risk factors and prevention strategies is essential in the reduction of these injuries. Therefore, the purpose of this systematic review is to identify the high-quality studies that examine the timing of athletic injury within an athletic event. We hypothesize that there will be high-quality studies that show an increased incidence of injury during the latter stages of play. We then hope to examine the contribution of fatigue to development of these injuries.

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were observed while performing the study selection and data extraction processes in this review.[8] The review was registered on the PROSPERO international prospective register for systematic reviews website (https://www.crd.york.ac.uk/prospero) on May 12, 2017. Review identification number is CRD42017062136.


  Materials and Methods Top


Literature search

A database search was conducted on February 22, 2017, in PubMed, Embase.com, SPORTDiscus with Full Text (EBSCOhost), and CINAHL Complete (EBSCOhost) using key words and controlled vocabulary related to epidemiology, fatigue, sports, athletes, and athletic injury. The search included all study types [an example PubMed search can be found in Appendix 1]. From this search, 559 articles were found and after duplicate articles were removed, 432 remained [Figure 1]. All 432 citations in the search were screened using our inclusion and exclusion criteria [Table 1] as were ten additional articles found by hand searching the references of selected articles. Two reviewers (HP and CK) individually screened the titles and abstracts. This review identified 98 citations accepted by either reviewer which were then sent to the next round of full-text review; articles that had disagreement between reviewers for inclusion were resolved by a third reviewer (TS). A total of 13 final articles met criteria in conjunction with ten handpicked studies resulting in 23 full-text articles accepted into this review.
Figure 1: PRISMA Flow Diagram of database search results and reviewer inclusion/exclusion of articles

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Table 1: Inclusion and exclusion criteria for articles generated through database search

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Appendix 1: Example database search

Pubmed:([“epidemiology”[Subheading] OR “epidemiology”[MeSH Terms] OR Epidemiology[tiab] OR rate[tiab] OR rates[tiab] OR incidence[tiab] OR incidences[tiab]] AND [“fatigue”[MeSH Terms] OR fatigue[tiab] OR exhaustion[tiab] OR “prolonged exercise”[tiab]] AND [“sports”[MeSH Terms] OR “sports”[tiab] OR Sport[tiab] OR “athletes”[MeSH Terms] OR “athletes”[tiab] OR player[tiab] OR players[tiab]] AND [“Athletic Injuries”[Mesh] OR “injuries”[Subheading] OR injury[tiab] OR injuries[tiab]]) AND (randomized controlled trial[pt] OR controlled clinical trial[pt] OR randomized[tiab] OR randomised[tiab] OR randomization[tiab] OR randomisation[tiab] OR placebo[tiab] OR drug therapy[sh] OR randomly[tiab] OR trial[tiab] OR groups[tiab] OR Clinical trial[pt] OR “clinical trial”[tiab] OR “clinical trials”[tiab] OR “evaluation studies”[Publication Type] OR “evaluation studies as topic”[MeSH Terms] OR “evaluation study”[tiab] OR evaluation studies[tiab] OR “intervention studies”[tiab] OR “intervention study”[tiab] OR “intervention studies”[tiab] OR “case-control studies”[MeSH Terms] OR “case-control”[tiab] OR “cohort studies”[MeSH Terms] OR cohort[tiab] OR “longitudinal studies”[MeSH Terms] OR “longitudinal”[tiab] OR longitudinally[tiab] OR “prospective”[tiab] OR prospectively[tiab] OR “retrospective studies”[MeSH Terms] OR “retrospective”[tiab] OR “follow up”[tiab] OR “comparative study”[Publication Type] OR “comparative study”[tiab] OR systematic[subset] OR “meta-analysis”[Publication Type] OR “meta-analysis as topic”[MeSH Terms] OR “meta-analysis”[tiab] OR “meta-analyses”[tiab]) NOT (Editorial[ptyp] OR Letter[ptyp] OR Case Reports[ptyp] OR Comment[ptyp]) NOT (animals[mh] NOT humans[mh])

Inclusion and exclusion criteria

Studies included acute musculoskeletal injuries sustained by athletes during a training or athletic event. All article types that reported acute contact and noncontact injuries to the upper and lower extremities were accepted for review. Types of musculoskeletal injury included strain, sprain, tendon rupture, contusions, etc. Injuries not accepted included concussions or traumatic brain injury (to maintain focus on specifically musculoskeletal effects), any spinal cord injuries (which is a highly traumatic neurological injury), and overuse injuries (injuries developed over time with no identifiable event and not in the acute time window of single athletic event). All articles accepted for review reported timing of musculoskeletal injury during the athletic events [Table 1].

Assessment of study quality

The Downs and Black grading tool was used to assess the quality of the 23 articles. This tool was chosen due to its ability to assess nonrandomized control trials, cohort studies, and case–control studies.[9] This checklist was shown to be successful and reliable in assessing the quality of nonrandomized studies.[9] The 27-question checklist was used; however, questions 4, 8, 14, 15, 19, 23, and 24 were removed because they lacked relevance to the study types of the final articles. Each article was graded by two reviewers (HP and CK) separately. If any discrepancy existed, the reviewers came to a consensus on the appropriate score [Table 2]. A higher score demonstrated a decreased risk of bias in the study. The average score for study quality was 15 out of 21 possible points (range, 11–20).
Table 2: Downs and Black scores for individual studies

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Levels of evidence

Levels of evidence were determined for each study using the Oxford Centre for Evidence-based Medicine Levels of Evidence 1 grading scale (HP and CK).[10] This scale determines the level of evidence by factoring in the study design type and quality of study design. The majority of studies in this review received a score of 2b [Table 3].
Table 3: Individual study Downs and Black score, Levels of Evidence, and study design

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Data extraction and analysis

Due to the variety of study types and statistical tests included, performing a meta-analysis on the data was not feasible. Consequently, data extraction consisted of cataloging the incidence of injury, timing of injury, and statistical significance reported in each study.


  Results Top


Of the 23 articles that were included for analysis, there were 8 rugby studies,[11],[12],[13],[14],[15],[16],[17],[18] 5 soccer,[19],[20],[21],[22],[23] 4 ice hockey,[24],[25],[26],[27] 1 Gaelic football,[28] 1 badminton,[29] 1 dance,[30] 1 wrestling,[31] 1 baseball,[32] and 1 multisport[33] [Table 4]. A total of 28,628 athletes were reported by 19 of the included papers; four studies listed only the number of teams.[18],[24],[25],[33] Athletes included amateurs and professionals, males, and females who ranged from high school-aged athletes to middle-aged adults. Eight of the 23 studies (35%) defined injury according to time-loss, 6 (26%) used medical attention, and 6 (26%) used both criteria to determine if an injury occurred. The other three articles had more specific determinants of injury including Achilles tendon rupture,[29] timeout called by the official for injury,[31] and pain or soreness in elbow or shoulder from pitching.[32] Stages of play were divided into halves in 12 studies (52%), periods in 4 studies (17%), quarters in 2 studies (9%), end of a recreational game or performance in 2 studies (9%), and number of pitches in 1 study (4%).
Table 4: Study authors, sport, definition of injury used in analysis, results of injury distribution, and author acknowledgement of fatigue contribution

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Twenty of the 23 articles (87%) found a higher incidence of injuries in the second half of play (or last two-quarters of play) or in the 2nd or 3rd periods. Of those twenty, 12 (60%) reported significantly higher injury incidence in the second half or in the 2nd and 3rd periods (as Chi-square and risk ratio assessments). Studies that did not report significance either did not run any statistical analysis or did not provide a P value.

Three studies found higher injury incidence in the beginning stages of play[15],[23] or an even distribution of injury throughout each stage of play.[27] These studies included reports from 27 ice hockey injuries,[27] 1694 rugby injuries,[15] and 20 soccer injuries.[23] Two studies found a higher incidence of injuries in the first half;[15],[23] however, only one study[15] found this to be statistically significant. One study examined high-school-aged varsity and junior varsity ice hockey players throughout training and competition for one (3 months) season and found an even distribution of injury throughout the 3 periods of hockey games.[27]


  Discussion Top


This review examines the literature describing the relationship between development of musculoskeletal injuries and timing during a single athletic event. Timing of injury during play can be used as a proxy for fatigue to see whether fatigue might be a risk factor for injury. While overall study quality was low, according to Downs and Black scoring,[9] results of this systematic review did reveal that the incidence of injury increased throughout the duration of competition or performance. Based on our results, any exploration of fatigue as a risk factor should include documentation of the time of injury (as a proxy for fatigue). While knowing the mechanism(s) of fatigue at the time of injury would be advantageous for designing training, the multitude of variables involved in fatigue in the competitive setting make any conclusion speculative. Such information can give valuable evidence for the design of interventions to prevent fatigue.

The current systematic review has identified twenty articles that link stage of play to injury risk and the results suggest that fatigue may play a role in increasing the risk of injury. Therefore, the ability to manage and delay the onset of fatigue could play a role in reducing musculoskeletal injuries. Ultimately, prevention strategies to delay fatigue must examine physical training strategies, nutrition, and rest. Appropriate physical training routines and effective use of new technology to monitor the acute: chronic training load are essential to promote fitness, delay fatigue, and prevent injury.[34] New technology may include heart rate variability monitoring in order to assess autonomic adaptations to training load. Nutrition and its effects on fatigue cannot be ignored as appropriate energy, and carbohydrate intake is essential to support training quality and the resulting adaptations that delay fatigue and improve performance.[35],[36] Adequate rest after both strenuous training regimens and competition promotes the development of fitness and performance and minimize the development of staleness and chronic fatigue.

While this review examined a number of different studies and determined injury incidence across multiple sports, there were several limitations in this review. The majority of studies included in this review were lower quality studies according to Downs and Black grading criteria.[9] All studies received a rating of 2b or higher regarding level of evidence,[10] yet the average score for study quality was 15 out of 20. Lower scores were often due to the lack of follow-up and absence of power analyses by the researchers. In many studies, injury data were pulled from a database where fatigue measurements were not recorded and rarely did the researchers follow-up with participants in the cohort to determine whether fatigue, a factor difficult to quantify during the competition, actually occurred. The lack of fatigue verification is also a significant limitation for these studies. Although a standard technique for measuring in-game fatigue may be difficult and has yet to be developed, there are many techniques that can be used to verify various aspects of fatigue such as a Profile of Mood States survey, presence of creatine kinase, changes in VO2 max and heart rate, or decreases in contraction forces.[37],[38] Without adequate follow-up and with little use of fatigue measurements, studies were unable to verify if fatigue actually occurred. There was not a consistent definition of injury across all studies, which made it difficult to adequately compare data. In addition, while some articles gave specific timing of injury,[7] others only provided comparisons between halves or periods in making comparison of later stages of play difficult. Consequently, due to a variety of statistical methods used among the studies and variable definitions of injury and play duration, a meta-analysis of the results was not possible.


  Conclusion Top


This review demonstrates an association between musculoskeletal injury and duration of play in a single athletic event. Establishing the presence of fatigue during competition is challenging and the use of time of the competitive setting as a proxy for fatigue suggests that musculoskeletal injuries happen more frequently later in either each half or later in the overall competition. While more recent injury prevention models integrate fatigue into the development of injury, mechanisms by which fatigue increases injury risk are still unclear. In future studies, verification of fatigue in athletes and examination of different management strategies are essential to further understand different fatigue mechanisms. Furthermore, it is critical that future injury prevention strategies examine the interactions of physical training, nutrition, and rest to combat the effects of fatigue and reduce fatigue-related musculoskeletal injury.

Clinical significance

This systematic review demonstrates that the incidence of musculoskeletal injury significantly increases during later stages of play and suggests that fatigue may be a risk factor. Musculoskeletal injuries in an athletic event can not only have acute effects on the player during the game or season, but also long-term effects on player career and future health. Consequently, this review provides compelling data that highlights the importance of further research on the mechanisms surrounding fatigue as a risk factor for injury and how these mechanisms can be addressed through preventative training to promote the overall health and safety of athletes.

Acknowledgment

The authors acknowledge Donald T. Kirkendall, ELS, a contracted medical editor, for his assistance in the preparation of the manuscript.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.





 
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