Anterior cruciate ligament injuries in elite and high school rugby players: a 11-year review

Reported Anterior Cruciate Ligament Injury Incidence in Adolescent Athletes Is Greatest in Female Soccer Players and Athletes Participating in Club Sports: A Systematic Review and Meta-analysis

PURPOSE

To identify the risk of anterior cruciate ligament (ACL) injury in adolescent athletes based on sex, sport, and sport affiliation.

METHODS

A literature search was performed using 3 online databases (PubMed, Cochrane Library, and EMBASE) from database inception to November 2023 per the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included studies consisted of Level I or II studies reporting on ACL injury exposures in time (hours) or injuries per 1,000 athlete-exposures (AEs) (1 game or practice) in adolescent athletes. Exclusion criteria consisted of non-English studies, case reports, animal/cadaveric studies, and review articles. Methodological quality and bias assessment of the included studies was assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. ACL injuries were analyzed and pooled to calculate incidence rates (IRs), per-season risk, and relative risk (RR) based on sex, sport, and sport affiliation (club sport participation vs school sport participation).

RESULTS

A total of 1,389 ACL injuries over 19,134,167 AEs were identified (IR, 0.075; 95% confidence interval [CI], 0.071-0.079). Of these, 670 ACL injuries were reported in female athletes over 7,549,892 AEs (IR, 0.089; 95% CI, 0.087-0.091) with 719 in males over 11,584,275 AEs (IR, 0.062; 95% CI, 0.058-0.067). The greatest RR for ACL injury in females was in soccer (RR, 3.12; 95% CI, 2.58-3.77) for AEs. The greatest per-season risk of ACL injuries reported in female athletes occurred in soccer (1.08%), basketball (1.03%), and gymnastics (1.01%). The greatest per-season risk of ACL injuries reported in male athletes occurred in football (0.82%), lacrosse (0.64%), and soccer (0.35%). Club sport participation, in both AEs (RR, 3.94; 95% CI, 3.19-4.87) and hours of exposure (RR, 1.57; 95% CI, 1.07-2.28), demonstrated an increased risk of ACL injury.

CONCLUSIONS

The risk of ACL injuries was 1.56-fold greater in adolescent female athletes compared with male athletes. The highest-risk sport for females was soccer. Participation in club sports possessed higher rates of injury compared with school sports.

LEVEL OF EVIDENCE

Level II; meta-analysis of Level I and II studies.

Race and Gender Differences in Anterior Cruciate Ligament Femoral Footprint Location and Orientation: A 3D-MRI Study

OBJECTIVE

The femoral tunnel position is crucial to anatomic single-bundle anterior cruciate ligament (ACL) reconstruction, but the ideal femoral footprint position are mostly based on small-sized cadaveric studies and elderly patients with a single ethnic background. This study aimed to identify potential race- or gender-specific differences in the ACL femoral footprint location and ACL orientation, determine the correlation between the ACL orientation and the femoral footprint location.

METHODS

Magnetic resonance images (MRIs) of 90 Caucasian participants and 90 matched Chinese subjects were used for reconstruction of three-dimensional (3D) femur and tibial models. ACL footprints were sketched by several experienced orthopedic surgeons on the MRI photographs. The anatomical coordinate system was applied to reflect the ACL footprint location and orientation of scanned samples. The femoral ACL footprint locations were represented by their distance from the origin in the anteroposterior (A/P) and distal-proximal (D/P) directions. The orientation of the ACL was described with the sagittal, coronal and transverse deviation angles. The ACL orientation and femoral footprint position were compared by the two-sided t-test. Multiple regression analysis was used to study the correlation between the orientation and femoral footprint position.

RESULTS

The average femur footprint A/P position was -6.6 ± 1.6 mm in the Chinese group and -5.1 ± 2.3 mm in the Caucasian group, (p < 0.001). The average femur footprint D/P position was -2.8 ± 2.4 mm in Chinese and - 3.9 ± 2.0 mm in Caucasians, (p = 0.001). The Chinese group had a mean difference of a 1.5 mm (6.1%) more posterior and 1.1 mm (5.3%) more proximal in the position from the flexion-extension axis (FEA). And the males have a sagittal plane elevation about 4-5° higher than females in both racial groups. Furthermore, for every 1% (0.40 mm) increase in A/P and D/P values, the sagittal angle decreased by about 0.12° and 0.24°, respectively; the coronal angle decreased by about 0.10° and 0.30°, respectively. For every 1% (0.40 mm) increase in D/P value, the transverse angle increased by about 0.14°.

CONCLUSION

The significant race- and gender-specific differences in the femoral footprint and orientation of the ACL should be taken in consideration during anatomic single-bundle ACL reconstruction. Furthermore, the quantitative relationship between the ACL orientation and the footprint location might provide some reference for surgeons to develop a surgical strategy in ACL single-bundle reconstruction and revision.

No difference in return to play rates between different elite sports after primary autograft ACL reconstruction

PURPOSE

To demonstrate return to play (RTP) rates, the level of RTP and time taken to RTP in different sports after anterior cruciate ligament reconstruction (ACL-R) and compare the differences between football and rugby. The secondary aims were to compare the differences in intra articular injuries and their treatments and reoperation rates between these sports.

METHODS

A retrospective review of a consecutive series of all primary ACL-R undertaken by the senior author between 2005 and 2019 was undertaken. Patients were included if they were elite athletes and were a minimum of 2 year post-primary autograft ACL-R. The outcomes measured were RTP (defined as participation in a professional match or in national/international-level competition in amateur sports), time to RTP after surgery and RTP level (Tegner score).

RESULTS

Three hundred and ninety-four elite athletes, with 420 ACL-Rs were included. 235 (55.9%) were in footballers and 125 (29.8%) were in rugby players. 399 (95.0%) of all elite athletes returned to competition at an average of 10.3 months after ACL-R. 386 (90.2% played at the same or higher level post-surgery. Although there was no difference in RTP rates between different sports, rugby players RTP significantly faster than footballers (9.6 vs 10.6 months, (p = 0.027). Footballers were more likely to rupture their ACL during jumping/landing manoeuvres and to receive a PT graft than rugby players. There were no other significant differences between football and rugby players regarding patient characteristics, intraoperative findings, re-rupture and re-operation rates.

CONCLUSIONS

Over 95% of all elite athletes RTP after primary ACL-R with 90% able to play at the same level. Rugby players RTP significantly faster than footballers.

LEVEL OF EVIENCE

Level IV.

Injury Rates, Mechanisms, Risk Factors and Prevention Strategies in Youth Rugby Union: What's All the Ruck-Us About? A Systematic Review and Meta-analysis

BACKGROUND

Rugby Union is a collision team sport played globally. Despite this, significant concerns have been raised regarding the sport's safety, particularly in youth players. Given this, a review of injury rates, risk factors and prevention strategies is required across different youth age groups as well as in males and females.

OBJECTIVE

The objective of this systematic review (SR) and meta-analysis was to investigate injury and concussion rates, risk factors and primary prevention strategies in youth rugby.

METHODS

To be included, studies were required to report either rates, risk factors or prevention strategies in youth rugby and to have a randomised controlled trial, quasi-experimental, cohort, case control, or ecological study design. Exclusion criteria included non-peer-reviewed grey literature, conference abstracts, case studies, previous systematic reviews and studies not written in English. Nine databases were searched. The full search strategy and list of sources are available and pre-registered on PROSPERO (Ref: CRD42020208343). Each study was assessed for risk of bias using the Downs and Black quality assessment tool. Meta-analyses were conducted using a DerSimonian Laird random effect model for each age group and sex.

RESULTS

Sixty-nine studies were included in this SR. The match injury rates (using a 24-h time-loss definition) were 40.2/1000 match hours (95% CI 13.9-66.5) in males and 69.0/1000 match hours (95% CI 46.8-91.2) in females. Concussion rates were 6.2/1000 player-hours (95% CI 5.0-7.4) for males and 33.9/1000 player-hours (95% CI: 24.1-43.7) for females. The most common injury site was lower extremity (males) and the head/neck (females). The most common injury type was ligament sprain (males) and concussion (females). The tackle was the most common event associated with injury in matches (55% male, 71% females). Median time loss was 21 days for males and 17 days for females. Twenty-three risk factors were reported. The risk factors with the strongest evidence were higher levels of play and increasing age. Primary injury prevention strategies were the focus of only eight studies and included law changes (n = 2), equipment (n = 4), education (n = 1) and training (n = 1). The prevention strategy with the most promising evidence was neuromuscular training. The primary limitations included a broad range of injury definitions (n = 9) and rate denominators (n = 11) used, as well as a limited number of studies which could be included in the meta-analysis for females (n = 2).

CONCLUSION

A focus on high-quality risk factor and primary prevention evaluation should be considered in future studies. Targeting primary prevention and stakeholder education remain key strategies in the prevention, recognition and management of injuries and concussions in youth rugby.

Injury Trends for School Rugby Union in Ireland: The Need for Position-specific Injury-prevention Programs

BACKGROUND

Concern has been raised over the injury risk to school Rugby union (Rugby) players and the potential long-term health consequences. Despite the increase in studies for this cohort, the influence of playing position on injury incidence and presentation is unclear.

PURPOSE

To describe the incidence, nature and severity of match injuries for school Rugby in Ireland overall, and as a function of playing position.

STUDY DESIGN

Prospective cohort study.

METHODS

Data were collected from 15 male (aged 16-19 years) school Senior Cup teams across 2 seasons. In total, 339 players participated in season 1, whereas 326 players participated in season 2. Injury data were recorded onto a bespoke online platform. Match exposure was also recorded.

RESULTS

The incidence rate of match injuries (24-hour time loss) was 53.6 per 1000 hours. Across both seasons, 6810 days were lost from play due to injury. Forwards (65.4 per 1000 hours) sustained significantly more (P < 0.05) injuries than backs (40.5 per 1000 hours). The head, shoulder, knee, and ankle were the most common injured body regions; however, forwards sustained significantly more (P < 0.05) head and shoulder injuries than backs. The tackle was responsible for the majority of injuries in both groups. The highest proportion of injuries occurred during the third quarter.

CONCLUSION

Clear differences in injury presentation and incidence were evident when comparing forwards versus backs. The high rate of head and shoulder injuries in the forwards suggest the need for more targeted injury-prevention strategies and further research on education and laws around the tackle event. The spike of injuries in the third quarter suggests that fatigue or inadequate half-time warm-up may be a contributing factor warranting further exploration.

CLINICAL RELEVANCE

This study demonstrates clear differences in injury presentation according to playing position in school Rugby and highlights the need for a more tailored approach to the design and implementation of injury-prevention strategies.

LEVEL OF EVIDENCE

Level 3.

Return to play protocols for musculoskeletal upper and lower limb injuries in tackle-collision team sports: A systematic review

Athletes in tackle-collision teams are at high risk of musculoskeletal injuries resulting in absence from play due to the high impact nature of the sport. There is a paucity of research to guide the management and assessment methods needed to facilitate the return to play (RTP) process. This review aimed to describe, synthesise and evaluate RTP protocols implemented for musculoskeletal injuries in tackle-collision teams. A systematic search of Scopus, PubMed, Web of Science and Ebsco Host was conducted for RTP management protocols and assessment modalities following upper and lower limb musculoskeletal injuries in tackle-collision team athletes. Prospective and retrospective quantitative controlled trials, cohort, case-control, case-series and cross-sectional observation studies published between January 2000 and March 2020 were considered. The main outcome measures were the proportion of athletes to RTP, associated time-loss and reinjury risk. 5265 articles were screened. 34 studies met the eligibility criteria of which 23 involved management and 11 assessment modalities. Management involved surgical or conservative strategies along with exercise-based rehabilitation. Assessment modalities included radiographic assessment, clinical evaluation and subjective ratings. Promising RTP management included progressive weight-bearing and exercised-based rehabilitation for ankle sprains as well as surgery, the use of a sling and exercise-based rehabilitation for shoulder instability. MRI scans showed promise in predicting time-loss following hamstring and calf strains in tackle-collision athletes. There are currently no clear guidelines for RTP after musculoskeletal injuries in tackle-collision sports. Future research should investigate efficient management strategies evaluated through valid and reliable assessment methods to better guide clinicians.

Anterior Cruciate Ligament Injury Incidence in Adolescent Athletes: A Systematic Review and Meta-analysis

BACKGROUND

The incidence of anterior cruciate ligament (ACL) injuries among adolescent athletes is steadily increasing. Identification of the highest risk sports for ACL injuries by sex and competitive setting (ie, practice vs match) is important for targeting injury prevention programs.

PURPOSE

To identify the risk of ACL injuries in adolescent athletes by sport, sex, and setting across a variety of common US and international sports.

STUDY DESIGN

Meta-analysis.

METHODS

Essentially, 3 online databases (PubMed, Embase, and Cochrane Library) were searched for all studies of ACL injuries per athlete-exposure (AE) or hours of exposure in adolescent athletes. Injuries were then pooled and incidence rates (IRs) reported per 1000 AEs or hours of exposure, with the relative risk (RR) of injuries calculated for sex-comparable sports. IRs per competitive setting (match vs practice) were also calculated.

RESULTS

A total of 1235 ACL injuries over 17,824,251 AEs were identified (IR, 0.069 [95% CI, 0.065-0.074]), with 586 of these injuries in girls across 6,986,683 AEs (IR, 0.084 [95% CI, 0.077-0.091]) versus 649 injuries in boys over 10,837,568 AEs (IR, 0.060 [95% CI, 0.055-0.065]). Girls had a higher overall rate of ACL injuries (RR, 1.40 [95% CI, 1.25-1.57]), with the most disproportionate risk observed in basketball (RR, 4.14 [95% CI, 2.98-5.76]). The risk of ACL injuries by sex was highest in girls' soccer (IR, 0.166 [95% CI, 0.146-0.189]) and boys' football (IR, 0.101 [95% CI, 0.092-0.111]). ACL injuries were over 8 (RR, 8.54 [95% CI, 6.46-11.30]) and 6 (RR, 6.85 [95% CI, 5.52-8.49]) times more likely to occur in a match versus a practice setting for female and male athletes, respectively.

CONCLUSION

The risk of ACL injuries overall approached nearly 1 per 10,000 AEs for female athletes, who were almost 1.5 times as likely as male athletes to suffer an ACL injury across all adolescent sports. A multisport female athlete was estimated to have a nearly 10% risk of ACL injuries over her entire high school or secondary school career. Specifically, male and female adolescents playing soccer, basketball, lacrosse, and football appeared at particular risk of injuries, a finding that can be used to target an injury intervention.

Return to Play After Patellar Tendon Autograft for Primary Anterior Cruciate Ligament Reconstruction in Rugby Players

Background:

There is scant literature on outcomes after anterior cruciate ligament (ACL) reconstruction in rugby players, and no prior study has evaluated the outcomes of bone–patellar tendon–bone (BTB) autograft ACL reconstruction.

Purpose:

To assess the rate of return to play, the timing of that return, and the subsequent graft reinjury rate among rugby players after ACL reconstruction with BTB autograft.

Methods:

The ACL registry at a single hospital was screened for professional and amateur rugby players who had undergone a primary ACL reconstruction with BTB autograft. Professional rugby players were those playing for one of the professional provincial teams in Ireland. Outcomes were analyzed for the rate and timing of return to play, functional outcomes, and subsequent graft ruptures. Additionally, outcomes were compared between professional and amateur athletes.

Study Design:

Case series; Level of evidence, 4.

Results:

A total of 126 patients with 24 months of follow-up were enrolled. The overall rate of return to play was 84.9%, with 75.4% returning to the same level of play; 8.7% of patients did not return to play secondary to non–knee-related issues. The mean time to return was 10.9 ± 4.9 months. Among professional rugby players, 93.3% were able to return at a mean time of 9.7 ± 4.4 months; 80% returned to the same level. The mean Anterior Cruciate Ligament–Return to Sport after Injury score was 78.4 ± 20.2, the Cincinnati knee score was 92.5 ± 8.0, the International Knee Documentation Committee score was 88.2 ± 8.1, and the Marx score was 9.7 ± 5.3. Two patients sustained a subsequent rerupture of the reconstructed ACL, and 4 players sustained a contralateral ACL injury within the follow-up interval of 2 years.

Conclusion:

Rugby players receiving BTB ACL reconstruction demonstrated good clinical outcomes with a high rate of return to sport, with the majority returning before 12 months. The rate of a subsequent ACL injury was low among the authors’ cohort at short-term follow-up.

Return to Play and Performance After Primary ACL Reconstruction in American Football Players: A Systematic Review

Background

Anterior cruciate ligament (ACL) injuries are among the most common sports-related injuries, and they can have a negative impact on players' ability to return to play (RTP). There is a paucity of literature focused on RTP after ACL reconstruction (ACLR) in collision sports.

Purpose

To characterize the impact that an ACL injury has on the ability to RTP and the post-ACLR performance level in American football players.

Study Design

Systematic review; Level of evidence, 4.

Methods

An electronic search was performed using the following databases: the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, PubMed, Embase, and the Cumulative Index to Nursing and Allied Health Literature. Included studies were written in English; were published since the year 2000; examined only American football players; and reported on RTP, performance, and/or career length after primary ACLR.

Results

The initial search yielded 442 unique studies. Of these, 427 were removed after screening, leaving 15 studies that met inclusion criteria. An additional 2 studies were identified in these studies' references, yielding a total of 17. The rate of RTP after ACLR for football players was 67.2% (1249/1859), and the mean time to return was 11.6 months (range, 35.8-55.8 weeks). Although considerable heterogeneity existed in the study design and outcomes measured, in general, a majority of football players experienced greater declines from their preinjury performance level than controls over the same time period.

Conclusion

An ACL injury negatively affected football players' ability to RTP and their post-ACLR performance. The degree of effect varied by several factors, including playing position, preinjury performance level, and National Football League Draft round. These results may be used by physicians and football players to develop reasonable expectations for returning to play and performance after an ACL injury.

Lay of the land: narrative synthesis of tackle research in rugby union and rugby sevens

Objectives

The purpose of this review was to synthesise both injury prevention and performance tackle-related research to provide rugby stakeholders with information on tackle injury epidemiology, including tackle injury risk factors and performance determinants, and to discuss potential preventative measures.

Design

Systematic review and narrative synthesis.

Data sources

PubMed, Scopus and Web of Science.

Eligibility criteria

Limited to peer-reviewed English-only publications between January 1995 and October 2018.

Results

A total of 317 studies were identified, with 177 in rugby union and 13 were in rugby sevens. The tackle accounted for more than 50% of all injuries in rugby union and rugby sevens, both at the professional level and at the lower levels, with the rate of tackle injuries higher at the professional level (mean 32/1000 player-hours) compared with the lower levels (mean 17/1000 player-hours). A player’s tackle actions and technical ability were identified as major risk factors for injury and a key determinant of performance.

Summary/conclusion

Evidence-based education, progressive tackle technique training with a high potential to transfer and law changes have been proposed as key modifiers of player tackle actions and technical ability. Conceivably, all three modifiers working in unison (as opposed to separately) will have a higher potential at reducing tackle injury risk while enhancing performance. With the guidance of tackle injury and performance studies, as well as stakeholder engagement, experiential and explorative tackle research has the potential to inspire innovative injury prevention and performance strategies.

Effect of Academic Grade Level on Return to Athletic Competition After Anterior Cruciate Ligament Reconstruction

BACKGROUND

After anterior cruciate ligament (ACL) reconstruction, 63% to 87% of high school athletes return to competition. Although physical and psychological factors are known contributors for failure to return to play, little attention has been paid to effect of academic grade level. Our purpose was to determine the influence of effect of academic grade level on return to competitive play. The primary hypothesis is that high school seniors who undergo ACL reconstruction or knee arthroscopy will be less likely to return to competitive play at 1 year than those in grades 9 to 11.

METHODS

We retrospectively reviewed high school athletes who injured their knee during competitive athletic activity and underwent arthroscopic knee surgery, including ACL reconstruction. We included those 14 to 18 years old at time of surgery and analyzed records for grade level, sporting activity, surgery details, and date of return to play. The definition of return to competitive play was return to same preinjury sport within 1 year of surgery and the sport had to be organized.

RESULTS

Our study group included 225 patients that underwent an ACL reconstruction and 74 had knee arthroscopy. Athletes undergoing ACL reconstructions were less likely to return to preinjury sport within 1 year than those undergoing knee arthroscopy (P=0.0163). Seniors were significantly less likely to return to play at 1 year than athletes in grades 9 to 11 after both ACL reconstruction (P<0.0001) and knee arthroscopy (P=0.0335). Although return to competitive play rates remained fairly constant within grades 9 to 11, a precipitous decline by 28.9% and 29.4% in return to play rates occurred in the ACL reconstruction and knee arthroscopy groups, respectively, between the junior and senior years of high school.

DISCUSSION

Although return to competition rates were lower for high school athletes undergoing ACL reconstruction than those undergoing knee arthroscopy, both had declines in return when the surgery occurs during their senior season. These data are useful when interpreting return to play rates. Future studies would benefit from further defining this relationship, or at least, noting the number of "senior" athletes studied.

LEVEL OF EVIDENCE

Therapeutic study-Level III.

A new technique of surgical planning for anterior cruciate ligament reconstruction: Feasibility Assessment of Shear Wave Elastography to Tendon of Semitendinosus Muscle

There is currently no method to quantify the quality of the harvested graft before anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to explore a method for measuring stiffness of the normal tendon of the semitendinosus muscle using shear wave elastography (SWE). Our investigation comprised two steps. First, we determined orientation of the semitendinosus tendon fibers in 20 lower legs of embalmed cadavers. Second, we investigated the feasibility of quantifying stiffness of the normal semitendinosus tendon by SWE in 24 subjects (48 legs: 24 male and 24 female subjects) in vivo. Measured values were compared between male and female subjects. The point at the intersection of the semitendinosus tendon with the axial section through the center of the patella mostly was the middle of the semitendinosus tendon in the cadavers. The SWE modulus in all of the subjects could be measured on this point in vivo. The SWE modulus of males and females were 474.0 ± 71.9 kPa and 396.9 ± 104.5 kPa, respectively. The SWE modulus of males was significantly larger than that of females (P < 0.01). This study demonstrates that stiffness of the tendon of the semitendinosus muscle can be measured by SWE. It also shows that tendon of the semitendinosus muscle in males is stiffer than in females. Clin. Anat. 31:404-408, 2018. © 2017 Wiley Periodicals, Inc.