Webster, Kate E.

Objective: Fatigue due to game play is often cited as a factor in musculoskeletal injuries; however, it is unclear whether or not this view is supported by published research findings. Given the importance researchers and practitioners place on the potential effects of game play with respect to injury, it is important to understand what inferences can be drawn from the collective research in this realm. This meta-analysis will consider the time of season and segment of the game, as it relates anterior cruciate ligament (ACL), groin, and hamstring injury occurrence. Data Sources: Database searches were run in PubMed, MEDLINE, SportDiscus, CINAHL, and Ausport, in addition to the inclusion of articles identified manually. Study Selection: Search terms were chosen to identify articles related to each of the 3 injuries of interest. There were no date limitations placed on the articles, as such, all published articles listed in the databases up to November 2017 were eligible for selection if they met the search criteria. Data Extraction: Initial searches yielded 1349 articles, and this was eventually reduced to 15 articles deemed suitable for inclusion in the meta-analysis, which provided 21 data sets. Data Synthesis: Comparing the first half with the second half of the season, there were no differences in ACL, groin, or hamstring injury occurrences [ACL: odds ratio (OR), 1.27; confidence interval (CI), 0.43-3.78, groin: OR, 1.79; CI, 0.63-5.06, and hamstring: OR, 1.16; CI, 0.88-1.53]. Similarly, there were no differences in injury occurrence between the first and second halves of the game for the ACL or hamstring injuries (ACL: OR, 0.43; CI, 0.47-7.92, hamstring: OR, 0.85; CI, 0.58-1.24). Conclusions: Findings from this meta-analysis determined that time in season or time in game does not influence risk of the ACL, groin, or hamstring injury. Commonly, many studies did not provide sufficient detail to be included in the meta-analysis. Consequently, it is recommended that future studies report data related to the timing of the injury within the season or game.

Background: Many studies have investigated factors that predict a return to sport participation after anterior cruciate ligament (ACL) reconstruction, but it is unclear whether the same factors are associated with a return to preinjury level of sport performance. Purpose: To identify factors that contribute to an athlete’s return to preinjury level of performance after ACL reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: A cohort of 222 patients (132 male, 90 female) who had ACL reconstruction surgery and completed a 12-month postoperative assessment were followed out to a mean 3 years (range, 2-4 years) to determine whether they had returned to their self-reported preinjury levels of sport performance. Rates of return to preinjury performance were calculated. Measures that had been recorded at the 12-month postoperative review—demographic (age, sex), sport activity level (Marx Activity Rating Scale, return to competition sport), knee laxity, limb symmetry (single and triple crossover hop), subjective function/symptoms (International Knee Documentation Committee subjective), and psychological readiness (Anterior Cruciate Ligament Return to Sport After Injury scale)—were compared between patients who returned to their preinjury levels of performance and those who did not. Univariate and multivariate logistic regression models were also used to prospectively determine the association between these measures and return to preinjury level of sport performance. Results: A total of 135 (61%) patients reported that they had returned to their preinjury levels of performance, with return rates similar between males (59%) and females (63%) and between those who had returned to competition at 12 months (62%) and those who had not (60%). There was no significant age difference between patients who returned to their preinjury levels of sport performance and those who did not; however, higher psychological readiness ( P < .0001), greater limb symmetry ( P < .05), higher subjective knee scores ( P = .01), and a higher activity level ( P < .04) were all associated with a return to performance. In the multivariate model, psychological readiness was the only variable that remained a significant predictor (odds ratio = 1.03; 95% CI, 1.01-1.04; P < .0001). Conclusion: A majority of athletes who returned to sport after ACL reconstruction reported that their performance was comparable with preinjury. Having a greater psychological readiness to return during rehabilitation was the most significant predictor of a subsequent return to comparable performance.

Background: Lower psychological readiness to return to sport has been reported for younger patients (≤20 years) who go on to a second anterior cruciate ligament (ACL) injury. However, changes in psychological readiness and specific psychological responses associated with second injury have not been identified. Purpose/Hypothesis: To identify changes in psychological readiness over time associated with a second ACL injury. It was hypothesized that younger patients who suffered a second injury would have smaller changes in psychological readiness to return to sport when compared with those who did not have a second injury. Study Design: Case-control study; Level of evidence, 2. Methods: Patients ≤20 years old at the time of surgery who had a primary ACL reconstruction procedure between June 2014 and June 2016 were recruited for this study. The short version of the Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) scale was completed by patients before their ACL reconstruction and repeated at 12 months after surgery to assess psychological readiness to return to sport. The primary outcome of interest was the relationship between the change in psychological readiness and second ACL injuries. Results: Among 115 young patients who returned to sport after ACL reconstruction, 21 (18%) experienced a second ACL injury. Injured patients did not show improvement in their ACL-RSI score between the preoperative assessment and 12-month time point (58.5 vs 60.8 points, P = .60) and had a significantly smaller change when compared with noninjured patients (9.2 vs 24.9 points, P = .01). When compared with the noninjured group, the injured group reported they were more nervous about playing sport, less confident in playing sport without concern for the knee, more frustrated with having to consider the knee with respect to sport, and more fearful of reinjuring the knee by playing sport ( P≤ .05). Conclusion: Injured patients exhibited less improvement in psychological readiness at a group level and reported different psychological characteristics with regard to return to sport at 12 months after ACL reconstruction as monitored by the ACL-RSI scale.

Background: Psychological responses after anterior cruciate ligament (ACL) injury and ACL reconstruction (ACLR) have been identified as predictors of return to sport but have not been investigated in relation to further injury. Purpose/Hypothesis: To determine whether psychological readiness to return to sport is associated with second ACL injury. It was hypothesized a priori that at both preoperative and 12-month postoperative time points, patients who sustained a second ACL injury would have lower psychological readiness than patients who did not have a second injury. Study Design: Cohort study; Level of evidence, 2. Methods: Patients who had a primary ACLR procedure between June 2014 and June 2016 completed the ACL–Return to Sport after Injury (ACL-RSI) (short version) scale before their ACLR and repeated the scale at 12 months after surgery to assess psychological readiness to return to sport. Patients were followed for a minimum of 2 years (range, 2-4 years) after surgery to determine further injury. The primary outcome was the relationship between ACL-RSI scores and the incidence of second ACL injury. Results: In 329 patients who returned to sport after ACLR, 52 (16%) sustained a second ACL injury. No difference in psychological readiness was observed at the preoperative time point, but patients who sustained a second injury trended toward lower psychological readiness at 12 months compared with noninjured patients (60.9 vs 67.2 points; P = .11). Younger (≤20 years) patients with injury had significantly lower psychological readiness to return to sport than young noninjured patients (60.8 vs 71.5 points; P = .02), but no difference was found in older patients (60.9 vs 64.6 points; P = .58). In younger patients, receiver operating characteristic curve analysis revealed a cutoff score of 76.7 points with 90% sensitivity to identify younger patients who sustained a second ACL injury. Conclusion: Younger patients with lower psychological readiness are at higher risk for a second ACL injury after return to sport.

Background: Clinical management of sport-related concussion typically involves a symptom checklist, clinical examination of mental status, and neurocognitive testing. However, recent studies have identified unresolved, impaired sensorimotor function after athletes return to sport. A review and meta-analysis of all current literature regarding risk of subsequent musculoskeletal (MSK) injury after concussion has yet to be published in the medical literature. Purpose/Hypothesis: To determine the odds that athletes will sustain MSK injury after concussion. It was hypothesized a priori that concussion would increase the risk for MSK injury. Study Design: Systematic review and meta-analysis. Methods: PubMed and Google Scholar were searched from January 2000 to November 2017. Reference lists of the included studies were manually searched. Two reviewers independently searched the literature for studies published in English that reported MSK injury after athletes returned to play following a concussion. Two independent reviewers completed data extraction using PRISMA guidelines and assessed study quality using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies from the National Institutes of Health. Random effects meta-analyses were used to calculate odds ratio (OR) and incidence rate ratio (IRR) of MSK injury after concussion. The primary study outcome of interest was the number of athletes who sustained MSK injury after concussion. Results: Eight studies met inclusion criteria for meta-analysis. Meta-analysis results indicated that athletes who had a concussion had 2 times greater odds of sustaining a MSK injury than athletes without concussion (OR, 2.11; 95% CI, 1.46-3.06). In addition, athletes with concussion demonstrated a higher incidence of MSK injury after return to sport compared with nonconcussed athletes (IRR, 1.67; 95% CI, 1.42-1.96). Further analysis showed that both male and female athletes with concussion were at an increased risk of MSK injury compared with their respective same-sex, nonconcussed controls (OR > 1.56, P < .01). Conclusion: Based on the evidence of higher risk of MSK injuries after concussion, standard clinical assessments for athletes with concussion should include not only physical symptoms and cognitive function before return to sport but also neuromuscular risk factors associated with increased risk for MSK injuries.

ABSTRACT Several meta‐analyses have been published on the effectiveness of anterior cruciate ligament (ACL) injury prevention training programs to reduce ACL injury risk, with various degrees of risk reduction reported. The purpose of this research was to perform a systematic review and meta‐analysis of overlapping meta‐analyses evaluating the effectiveness of ACL injury prevention training programs so as to summarize the amount of reduction in risk for all ACL and non‐contact ACL injuries into a single source, and determine if there were sex differences in the relative efficacy of ACL injury prevention training programs. Five databases (Medline, PubMed, Embase, CINAHL, and Cochrane) were searched to identify meta‐analyses that evaluated the effectiveness of ACL injury prevention training programs on ACL injury risk. ACL injury data were extracted and the results from each meta‐analysis were combined using a summary meta‐analysis based on odds ratios (OR). Eight meta‐analyses met eligibility criteria. Six of the eight only included data for female athletes. Summary meta‐analysis showed an overall 50% reduction (OR = 0.5 [0.41–0.59]; I 2 = 15%) in the risk of all ACL injuries in all athletes and a 67% reduction (OR = 0.33 [0.27–0.41]; I 2 = 15%) for non‐contact ACL injuries in females. This paper combines all previous meta‐analyses into a single source and shows conclusive evidence that ACL injury prevention programs reduce the risk of all ACL injuries by half in all athletes and non‐contact ACL injuries by two‐thirds in female athletes. There is insufficient data to make conclusions as to the effectiveness of ACL injury prevention programs in male athletes. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2696–2708, 2018.

Background: Anterior cruciate ligament (ACL) injury has a significant psychological effect, and a negative psychological state is a commonly cited reason for a reduction or cessation of sports participation after ACL reconstruction (ACLR) surgery. Purpose: To identify factors that contribute to an athlete’s psychological readiness to return to sport (RTS) after ACLR. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A cohort of 635 athletes (389 male, 246 female) who underwent ACLR and had been cleared to RTS completed the Anterior Cruciate Ligament–Return to Sport After Injury (ACL-RSI) scale at an average 12 months (range, 11-24 months) after surgery. Demographics (age, sex), sporting outcomes (preinjury frequency), surgical timing (injury to surgery interval), clinical factors (laxity), functional measures (single-limb hop symmetry), and symptoms of pain and function (International Knee Documentation Committee subjective) were also taken, and univariate and multiple regression models were used to determine the association between these and the psychological readiness of the athlete to RTS (ACL-RSI scores). Data for the entire cohort were initially analyzed; then, patients were grouped according to whether they had returned to competitive sport, and the analysis repeated for each group (return/nonreturn). Results: Univariate analysis for the entire group showed that all of the following had a positive effect on psychological readiness: male sex (β = 5.8; 95% CI, 2-10), younger age (β = −0.2; 95% CI, –0.4 to 0.01), a shorter interval between injury and surgery (β = −0.1; 95% CI, −0.1 to −0.02), a higher frequency of preinjury sport participation (β = 5.4; 95% CI, 2-9), greater limb symmetry (β = 0.5; 95% CI, 0.3-0.6), and higher subjective knee scores (β = 1.3; 95% CI, 1.1-1.4). In the multivariate model, subjective knee scores and age significantly accounted for 37% of the variance in psychological readiness ( r 2 = 0.37, P < .0001). The only difference between the groups who had and had not returned to sport was that female sex was a significant contributor for the nonreturn group. Conclusion: Self-reported symptoms and function were most associated with psychological readiness to RTS after ACLR surgery. Male patients who participated frequently in sport before ACL injury had higher psychological readiness. Conversely, female patients had a more negative outlook and may therefore benefit more from interventions designed to facilitate a smooth transition back to sport.

General and Critical Review Format: The evolution of clinical practice and medical technology has yielded an increasing number of clinical measures and tests to assess a patient's progression and return to sport readiness after injury. The plethora of available tests may be burdensome to clinicians in the absence of evidence that demonstrates the utility of a given measurement. Objective: Thus, there is a critical need to identify a discrete number of metrics to capture during clinical assessment to effectively and concisely guide patient care. Data Sources: The data sources included Pubmed and PMC Pubmed Central articles on the topic. Therefore, we present a systematic approach to injury risk analyses and how this concept may be used in algorithms for risk analyses for primary anterior cruciate ligament (ACL) injury in healthy athletes and patients after ACL reconstruction. Main Results: In this article, we present the five-factor maximum model, which states that in any predictive model, a maximum of 5 variables will contribute in a meaningful manner to any risk factor analysis. Conclusions: We demonstrate how this model already exists for prevention of primary ACL injury, how this model may guide development of the second ACL injury risk analysis, and how the five-factor maximum model may be applied across the injury spectrum for development of the injury risk analysis.