Clinical Tests Can Be Used to Screen for Second Anterior Cruciate Ligament Injury in Younger Patients Who Return to Sport

Association between passing return-to-sport testing and re-injury risk in patients after anterior cruciate ligament reconstruction surgery: a systematic review and meta-analysis

Background

Inconsistent results have been obtained regarding the association between return-to-sport (RTS) testing and the risk of subsequent re-injury following anterior cruciate ligament reconstruction (ACLR). We therefore conducted a systematic review and meta-analysis to assess the potential association between passing of RTS and the risk of re-injury for patients after ACLR.

Methods

This meta-analysis was registered in INPLASY with the registration number INPLASY202360027. The electronic databases MedLine, EmBase, and the Cochrane library were systematically searched to identify eligible studies from their inception up to September 2023. The investigated outcomes included knee injury, secondary ACL, contralateral ACL injury, and graft rupture. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the random-effects model.

Results

A total number of nine studies involving 1410 individuals were selected for the final quantitative analysis. We noted that passing RTS test was not associated with the risk of subsequent knee injury (OR: 0.95; 95% CI: 0.28-3.21; P = 0.929), secondary ACL injury (OR: 0.98; 95% CI: 0.55-1.75; P = 0.945), and contralateral ACL injury (OR: 1.53; 95% CI: 0.63-3.71; P = 0.347). However, the risk of graft rupture was significantly reduced (OR: 0.49; 95% CI: 0.33-0.75; P = 0.001).

Conclusions

This study found that passing RTS test was not associated with the risk of subsequent knee injury, secondary ACL injury, and contralateral ACL injury, while it was associated with a lower risk of graft rupture. Thus, it is recommended that patients after ACLR pass an RTS test in clinical settings.

Evaluation of hop test movement quality to enhance return to sport testing. A cross-sectional study

Introduction

Return to Sport tests with functional hop tests are often used to decide when a person is ready to return to sport after an anterior cruciate ligament (ACL) injury. Poor movement quality, such as knee valgus, hip adduction and hip internal rotation is considered a risk factor for ACL injury. However, it is unclear whether existing tests adequately cover the aspect of movement quality. This study aims to investigate whether there is a relationship between the calculated limb symmetry index (LSI) of hop tests as an indication of performance and the total score of the "Quality First" assessment (movement quality). The second aim is to examine the reliability of the newly developed "Quality First" assessment for evaluating movement quality in hop tests.

Methods

The cross-sectional study recruited 34 patients with an ACL reconstruction. The vertical hop, single-leg hop for distance, and side hop tests were performed and recorded. The video recordings were assessed using the "Quality First" assessment. The Spearman correlation coefficient was calculated using the LSI and the "Quality First" total score. Intraclass correlation coefficients (ICC) and standard error of measurements (SEM) were used to calculate intra- and interrater reliability. In addition, the minimal detectable change (MDC) was determined.

Results

The correlation test between the LSI and the "Quality First" total score showed no correlation for all three jumps (r = -0.1-0.02/p-value = 0.65-0.93). The interrater reliability of the "Quality First" assessment showed fair to good reliability (ICC2: 0.45-0.60), with SEM ranging from 1.46 to 1.73 and the MDC from 4.06 to 4.8. Intrarater reliability was good to excellent (ICC3: 0.73-0.85), with SEM values ranging from 0.89 to 1.09 and the MDC from 2.47 to 3.01.

Conclusion

The quality of movement, measured with the "Quality First" assessment, indicated no correlation with the calculated LSI from jump performance, therefore movement quality should also be examined in Return to Sport tests. The "Quality First" assessment shows fair to good reliability when used by different raters. When used multiple times by the same rater, the assessment has good to excellent reliability.

Reconsideration of Return-to-Sport Decision-Making After Pediatric ACL Injury: A Scoping Review

CONTEXT

Up to 90% of pediatric athletes return to sport (RTS) after anterior cruciate ligament reconstruction (ACL-R); however, <50% RTS at the same level and second ACL injury rates are up to 32%.

OBJECTIVES

(1) Determine which physical and patient-reported outcome measures guide clinical decision-making on RTS in pediatric athletes after ACL-R and (2) present a framework with insights from cognitive and neurophysiological domains to enhance rehabilitation outcomes.

DATA SOURCES

PubMed, CINAHL, Embrase, and Cochrane library databases and gray literature.

STUDY SELECTION

Data on pediatric (<18 years) ACL-R patients, RTS, tests, and decision-making were reported in 1214 studies. Two authors independently reviewed titles and abstract, excluding 962 studies. Gray literature and cross-reference checking resulted in 7 extra studies for full-text screening of 259 studies. Final data extraction was from 63 eligible studies.

STUDY DESIGN

Scoping review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Details on study population, aims, methodology, intervention, outcome measures, and important results were collected in a data chart.

RESULTS

Studies included 4456 patients (mean age, 14 years). Quadriceps and hamstring strength (n = 25), knee ligament arthrometer (n = 24), and hop tests (n = 22) were the most-reported physical outcome measures guiding RTS in <30% of studies with cutoff scores of limb symmetry index (LSI) ≥85% or arthrometer difference <3 mm. There were 19 different patient-reported outcome measures, most often reporting the International Knee Documentation Committee (IKDC) (n = 24), Lysholm (n = 23), and Tegner (n = 15) scales. Only for the IKDC was a cutoff value of 85% reported.

CONCLUSION

RTS clearance in pediatric ACL-R patients is not based on clear criteria. If RTS tests were performed, outcomes did not influence time of RTS. Postoperative LSI thresholds likely overestimate knee function since biomechanics are impaired despite achieving RTS criteria. RTS should be considered a continuum, and biomechanical parameters and contextual rehab should be pursued with attention to the individual, task, and environment. There is a need for psychological monitoring of the ACL-R pediatric population.

Surgical techniques in the management of pediatric anterior cruciate ligament tears: Current concepts

Background

Anterior cruciate ligament injury in the child and adolescent patient remains a controversial topic when considering management, especially regarding surgical choices. Treatment variations are seen not just when comparing different countries but also within nations. This arises partly as contemporary treatment is mostly inferred from the adult population who physiologically and in terms of outcomes differ significantly from children. There is an increasing body of evidence for this cohort of patients who have specific challenges and difficulties when determining the optimum treatment.

Methods

Within this article, we will summarize the current evidence for surgical management of anterior cruciate ligament injury for the pediatric patient.

Results and Conclusions

There remain many controversies and gaps inthe treatment of Paediatric Anterior cruciate ligament reconstruction and this high risk cohort continues to cause difficulty in identifying the best mode of surgical management.

Level of evidence

level IV.

Return to Sports: A Risky Business? A Systematic Review with Meta-Analysis of Risk Factors for Graft Rupture Following ACL Reconstruction

BACKGROUND

The risk of sustaining a graft rupture after anterior cruciate ligament reconstruction (ACLR) is high. Contributing risk factors are, however, still not clearly identified.

OBJECTIVE

The aim of this systematic review was to identify and quantify risk factors for graft rupture after ACLR.

METHODS

A systematic review with meta-analysis (PROSPERO CRD42020140129) based on PRISMA guidelines was performed. MEDLINE, CINAHL and EMBASE were searched from inception to September 2021. Prospective and retrospective studies addressing risk factors for graft rupture after ACLR in males/females of all ages were considered. Meta-analyses using a random effect model (effect measure: odds ratio [OR] with 95% confidence interval [CI]) were performed. The GRADE tool was used to assess evidence quality.

RESULTS

Following full-text screening of 310 relevant papers, 117 were eventually included, incorporating up to 133,000 individuals in each meta-analysis. Higher Tegner activity level (≥ 7 vs < 7) at primary injury (OR 3.91, 95% CI 1.69-9.04), increased tibial slope (degrees) (OR 2.21, 95% CI 1.26-3.86), lower psychological readiness to return to sport (RTS) (OR 2.18, 95% CI 1.32-3.61), early surgery (< 12 vs ≥ 12 months) (OR 1.87, 95% CI 1.58-2.22), RTS (pre-injury level) (OR 1.87, 95% CI 1.21-2.91) and family history of ACL injury (OR 1.76, 95% CI 1.34-2.31) were all associated with increased odds of graft rupture. Higher age (OR 0.47, 95% CI 0.39-0.59), female sex (OR 0.88, 95% CI 0.79-0.98), fewer self-reported knee symptoms pre-reconstruction (OR 0.81, 95% CI 0.69-0.95) and concomitant cartilage injuries (OR 0.70, 95% CI 0.62-0.79) instead decreased the odds. Meta-analysis revealed no association between body mass index, smoking, joint laxity, RTS time, knee kinematics, muscle strength or hop performance and graft rupture.

CONCLUSION

Conspicuous risk factors for graft rupture were mainly sports and hereditary related. Few studies investigated function-related modifiable factors or included sports exposure data.

Return to Sport Activities and Risk of Reinjury Following Primary Anterior Cruciate Ligament Reconstruction

This article examines the elements that affect the return to sport (RTS) and the risk and percentages of reinjury following a prior primary anterior cruciate ligament reconstruction (ACLR). The prevalence of RTS following ACLR ranges from 71% to 83%. Concerning elements affecting RTS, a limb symmetry index score of 90 or more duplicates the likelihood of RTS and triplicates it when the International Knee Documentation Committee (IKDC) score is 95 or more, irrespective of age. Other elements recognized to be preindicative of RTS at 1 year include complete rehabilitation, age ≤25, and higher IKDC scores. The prevalence of reinjury following ACLR ranges from 1.5% to 37.5% (between 9% and 29% in the majority of reports). It has been published that 1 in 5 individuals suffers reinjury to either knee, and that male individuals are more prone to reinjure following ACLR. The highest percentage of ACLR reinjury happens in younger male (<18 years), being substantially higher than in female of the same age. Passing a combination of functional tests with predetermined cut-off points utilized as RTS criteria are related diminished ACLR reinjury percentages.

Association Between Meeting Return-to-Sport Criteria and Psychological Readiness to Return to Sport After Anterior Cruciate Ligament Reconstruction

Background:

The relationship between meeting return-to-sport criteria and psychological readiness after anterior cruciate ligament (ACL) reconstruction is unknown.

Purposes:

To examine (1) whether patients who met 1 of the criteria for return to sport had higher psychological readiness than those who did not meet any of the criteria and (2) if those who met more criteria had higher psychological readiness.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

This study included 144 patients who underwent unilateral ACL reconstruction. All patients had regularly participated in some sport activities before an ACL rupture. At 12 months postoperatively, each patient completed 3 knee function tests (isokinetic quadriceps strength, isokinetic hamstring strength, and single-leg hop distance) and 2 self-reported measures (International Knee Documentation Committee [IKDC] 2000 subjective form and ACL–Return to Sport after Injury [ACL-RSI] scale); the ACL-RSI scale was used to measure psychological readiness to return to sport. The 4 criteria for return to sport were a limb symmetry index (LSI) ≥90% for each of the 3 function tests in addition to an IKDC score ≥90. Multivariate regression analysis was used to determine the association between meeting the individual criteria and the ACL-RSI score. In addition, the patients were divided into 5 groups according to the number of criteria met, and the Kruskal-Wallis and Steel-Dwass tests were used to compare the ACL-RSI scores among the groups.

Results:

Overall, 23 patients (16.0%) met none of the criteria for return to sport, 27 (18.7%) met 1 of the criteria, 34 (23.6%) met 2 criteria, 35 (24.3%) met 3 criteria, and 25 (17.4%) met all 4 criteria. Meeting the criteria for the hamstring strength LSI (P = .002), single-leg hop distance LSI (P = .004), and IKDC subjective score (P < .001) was each associated with higher ACL-RSI scores. Significant differences in ACL-RSI scores were found between patients who met none versus 2, 3, and 4 of the return-to-sport criteria (P < .001 for all) and between patients who met 1 versus 4 criteria (P < .001).

Conclusion:

Meeting return-to-sport criteria was positively associated with psychological readiness, and the patients who met multiple criteria had higher psychological readiness.

Screening Tests for Assessing Athletes at Risk of ACL Injury or Reinjury-A Scoping Review

Various tests are available to assess athletes for factors associated with their susceptibility and risk of anterior cruciate ligament (ACL) injury or reinjury; however, it is unclear which tests are clinically meaningful and what should be considered when using them. Therefore, the aim of this scoping review was to screen and summarize testing and to derive evidence-based recommendations for clinicians, practitioners and future research. Five databases were searched to identify studies addressing musculoskeletal morphology or functional-performance-related screening tests with a clear conceptual link or an evidence-based relationship to ACL (re)injury. A quality rating was carried out using the National Institutes of Health (NIH) Study-Quality Assessment Tool. Six different categories of common screening tests were identified: balance and postural control, gait- and running-related tests, joint laxity, joint morphology and anthropometrics, jump tests and strength tests. Predicting future injury in a complex, dynamic system based on a single screening test is methodologically challenging, which is also reflected in the highly controversial findings in the literature regarding potential associations between specific screening tests and the occurrence of ACL injuries and reinjuries. Nonetheless, various screening tests can provide clinically relevant information on ACL-(re)injury-related factors and help to provide tailored preventive measures. A selection of corresponding evidence-based recommendations is derived and presented in this scoping review.

Return to play testing following anterior cruciate reconstruction - A systematic review & meta-analysis

PURPOSE

The purpose of this study is to systematically review the evidence regarding return to sport evaluation following ACL reconstruction and evaluate the relationship between testing and secondary ACL injury.

METHODS

A systematic review of the literature with PubMed, Ovid MEDLINE, Cochrane Reviews, was performed on June, 2020 based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were included if they compared outcomes following passing and failing RTP testing subsequent to ACLR. Clinical outcomes were compared, with all statistical analysis performed using Review Manager Version 5.3. Correlation was calculated with Spearman testing.

RESULTS

Overall, 8 studies with 1224 patients were included in the analysis. Overall, 34.3% (420/1224) patients passed the RTP testing. Those who passed the RTP testing had a statistically significant 47% lower rate of ACL graft re-rupture compared to those who did not pass the RTP testing (p = 0.03). However, there was a slightly higher, albeit not statistically significant, rate of contralateral ACL rupture in those who passed the RTP testing compared to those who did not (p = 0.42). There was a strong positive correlation between a high rate of patients passing the ACL RTP testing in studies and ACL graft rupture rate in those who failed (0.80).

CONCLUSION

Passing RTP testing following ACLR results in a lower rate of ACL graft rupture, but not contralateral ACL injury. Further evaluation and standardization of RTP testing is necessary in order to increase reliability in identifying patients at risk for re-injury after ACLR.

LEVEL OF EVIDENCE

Level of Evidence III.

A comparison of kinematic demands placed on the knee and hip during two ACL return-to-sport screening maneuvers and an agility test

OBJECTIVES

This study's purpose was to compare the kinematic demands placed on the knee and the hip during various biomechanical tests.

DESIGN

Retrospective cross-sectional design.

SETTING

A university research laboratory.

PARTICIPANTS

The study sample consisted of 70 NCAA Division I female athletes.

MAIN OUTCOME MEASURES

During the performance of three test maneuvers, a drop vertical jump (DVJ), single leg cross over hop (COH) and modified T-test (AT), the hip and knee joint angles at maximum knee valgus were obtained from marker displacement data collected using a 20-camera motion analysis system. A linear mixed model was used to compare the effect of test on joint angle.

RESULTS

A significant difference (p < 0.001) in the frontal and sagittal plane position of the knee and hip was noted between the DVJ, COH, and AT tests at maximum knee valgus.

CONCLUSIONS

The DVJ, COH, and AT maneuvers do not appear to place the same kinematic stress on the knee, supporting the need for the development of return to sport tests that mimic on field demands.

Terminal knee extension deficit and female sex predict poorer quadriceps strength following ACL reconstruction using all-soft tissue quadriceps tendon autografts

PURPOSE

The all-soft tissue quadriceps tendon (QT) autograft is becoming increasingly popular for ACL reconstruction (ACLR); however, studies reporting strength recovery and early outcomes after QT autograft are limited with patient samples composed of predominantly males. The primary purpose was to characterize early, sex-specific recovery of strength, range of motion (ROM), and knee laxity in a large cohort of patients undergoing primary ACLR with standardized harvest technique of the all-soft tissue QT autograft. The secondary purpose was to examine the influence of demographic factors and clinical measures on 6-month quadriceps strength.

METHODS

Patients 14-25 years who underwent primary, unilateral ACLR with all-soft tissue QT autografts were prospectively followed. Knee laxity and ROM were collected at 6 weeks, 3 and 6 months; while, quadriceps normalized torques and limb symmetry indices (LSI) were collected at 3 and 6 months using isokinetic dynamometry at 60°/s. Two-way ANOVAs with repeated measures were conducted to determine recovery over time and between sexes. Stepwise linear multiple regressions were conducted to determine predictors of 6-month quadriceps strength.

RESULTS

Three-hundred and twenty patients were included (18 ± 3 years; 156 males:164 females; BMI = 24 ± 4 kg/m²) with no early graft failures within the study period. For strength, there were significant main effects of time (p < 0.001) and sex (p < 0.001), indicating similar improvement from 3 to 6 months with males demonstrating greater quadriceps LSI (6 months: 72.1 vs 63.3%) and normalized strength (6 months: 2.0 vs 1.6 Nm/kg). A significantly higher proportion of females had knee extension ROM deficits ≥ 5° compared to males at 6 weeks (61 vs 39%; p = 0.002). Female sex and 3-month extension ROM deficits were identified as significant predictors of 6-month quadriceps LSI (R² = 0.083; p < 0.001). Female sex, BMI, and 6-week extension ROM deficits were identified as significant predictors of 6-month normalized quadriceps strength (R² = 0.190; p < 0.001).

CONCLUSIONS

Females had decreased quadriceps strength and greater extension ROM deficits at 3 and 6 months following ACLR using all-soft tissue QT autografts. Female sex, higher BMI, and loss of extension ROM were independent predictors of poorer quadriceps strength at 6 months. There were no early graft failures, and laxity remained within normal ranges for both males and females. Surgeons and rehabilitation clinicians should be aware of the increased risk of postoperative loss of extension ROM in females and its implications on quadriceps strength recovery.

LEVEL OF EVIDENCE

III.

Does sex affect second ACL injury risk? A systematic review with meta-analysis

OBJECTIVE

To determine sex-based differences in risk of a second ACL injury (overall and by laterality) following primary ACL reconstruction in athletes who are attempting to return to sport.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

Systematic search of five databases conducted in August 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies reporting sex-based differences in the incidence of second ACL injury in athletes attempting to return-to-sports and who were followed for at least 1 year following primary ACL reconstruction.

RESULTS

Nineteen studies were included in this review, with seven studies excluded from the primary meta-analysis due to high risk of bias. The remaining 12 studies (n=1431 females, n=1513 males) underwent meta-analysis, with all 19 studies included in a sensitivity analysis. Total second ACL injury risk was 21.9% (females: 22.8%, males: 20.3%). Females were found to have 10.7% risk of an ipsilateral ACL injury and 11.8% risk of a contralateral ACL injury. Males were found to have 12.0% risk of an ipsilateral ACL injury and 8.7% risk of a contralateral ACL injury. No statistically significant differences were observed for total second ACL injury risk (risk difference=-0.6%, 95% CI -4.9 to 3.7, p=0.783, I²=41%) or contralateral ACL injury risk (risk difference=1.9%, 95% CI -0.5% to 4.4%, p=0.113, I²=15%) between sexes. Females were found to have a 3.4% absolute risk reduction in subsequent ipsilateral ACL injury risk compared with males (risk difference=-3.4%, 95% CI -6.7% to -0.02%, p=0.037, I²=35%).

CONCLUSION

Both sexes have >20% increased risk of experiencing a second ACL injury. Any difference in the absolute risk of either a subsequent ipsilateral or contralateral ACL injury between sexes appears to be small.

REGISTRATION

PROSPERO (CRD42020148369).

Poor Validity of Functional Performance Tests to Predict Knee Injury in Female Soccer Players With or Without Anterior Cruciate Ligament Reconstruction

BACKGROUND

Various tests have been developed to evaluate athletes' functional performance and for use as screening tools for injury prediction. Further validation of their accuracy to predict injury is needed.

PURPOSE

To investigate the validity of predetermined cutoffs used to differentiate between high- and low-risk players in different functional performance tests to predict (1) anterior cruciate ligament (ACL) injury or (2) severe traumatic knee injury in a cohort of female soccer players with a primary unilateral ACL reconstruction and a cohort of knee-healthy players.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 117 active female soccer players (mean age ± SD, 20 ± 2 years) an average of 19 ± 9 months after ACL reconstruction and 119 knee-healthy players (age, 19 ± 3 years) were prospectively followed up for 2 years for new knee injuries. At baseline, all players underwent tests to assess postural control (Star Excursion Balance Test), hop performance (single-leg hop for distance, side hop), and movement asymmetries in the lower limbs and trunk (drop vertical jump [DVJ], tuck jump). The predictive validity of the test cutoffs to identify players who would sustain an ACL injury or a severe traumatic knee injury (absence from soccer play, >28 days) was assessed. The risk ratio (RR), area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were calculated.

RESULTS

A total of 46 players (39%) with ACL reconstruction sustained 48 severe knee injuries, including 28 ACL ruptures. Of the knee-healthy players, 13 (11%) sustained 14 severe knee injuries, including 8 ACL ruptures. No association was found between the predetermined functional performance test cutoffs and the risk of a new ACL injury or severe knee injury in players with ACL reconstruction. In knee-healthy players, the only variable associated with future ACL injury was ≥6.5 cm knee valgus in the frontal plane (any knee) in the DVJ (RR, 4.93; 95% CI, 1.04-23.40; P = .045), but with only fair predictive validity (AUC, 0.7; sensitivity, 0.75; specificity, 0.65).

CONCLUSION

In our cohorts of female soccer players, the validity of commonly used functional performance tests to predict new knee injuries was poor. Only knee valgus during the DVJ was associated with new ACL injuries in knee-healthy players, but with only fair predictive validity.

Test Batteries After Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review

CONTEXT

There is a lack of consensus regarding test batteries for return to sport (RTS) after anterior cruciate ligament reconstruction (ACLR).

OBJECTIVE

To report the RTS test batteries for individuals after ACLR and to examine alignment with the American Academy of Orthopaedic Surgeons (AAOS) Appropriate Use Criteria (AUC). Finally, to examine how published RTS batteries prior to the AAOS AUC (2010-2015) compared with those after publication of the AUC (2016-2020).

DATA SOURCE

A systematic search of PubMed (2010-2020).

STUDY SELECTION

Studies were included if they were published from 2010 to 2020, patients underwent primary ACLR and were tested between 6 months and 2 years postoperatively and included a minimum of 2 assessments. Studies were excluded if patients were tested outside the designated time; had undergone a revision, contralateral, or multiligament injury; included healthy participants; were level 5 evidence or the study was a systematic review. A total of 1012 articles were reviewed and 63 met the criteria.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Information regarding the RTS batteries and patient demographics were extracted from the included articles.

RESULTS

A total of 63 studies met the inclusion and exclusion criteria (22 from 2010-2015 and 41 from 2016-2020). The most common RTS batteries included the hop test, quadriceps strength test, and patient-reported outcome measures. No study met all 7 AUC; the most common criteria met were functional skills (98.4%), followed by confidence (22.2%), then range of motion and knee stability (20.6%).

CONCLUSION

The test batteries in the current literature show high variability and a lack of essential components necessary for RTS. No study met the AUC guidelines, suggesting a disconnect between recommended guidelines and clinical practice. Test battery research has expanded over the past decade; however, standardized, clinically applicable batteries that encompass all criteria are needed.

Second ACL Injury Rates in Younger Athletes Who Were Advised to Delay Return to Sport Until 12 Months After ACL Reconstruction

Background:

Younger patients are at increased risk for anterior cruciate ligament (ACL) graft rupture and contralateral injury after ACL reconstruction (ACLR). Increasing the amount of time between surgery and the resumption of competitive sport may reduce this risk.

Purpose:

To determine the rates of graft rupture and injury to the contralateral native ACL at 3- to 5-year follow-up in younger patients who were advised to delay a return to competitive sport until 12 months after surgery and compare this with a nondelayed cohort.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

The primary study cohort consisted of 142 eligible patients aged <20 years when they underwent their first primary ACLR. All were informed about the risk of further injury and advised not to return to competitive sport before 12 months postoperatively. Return-to-sport status and the number of subsequent ACL injuries (graft rupture or a contralateral injury to the native ACL) were determined at 3- to 5-year follow-up and compared with a historic cohort of 299 patients with ACLR who were not advised to delay their return to sport for a set period. The cohorts were then combined, and injury rates were compared between those who returned to sport before and after 12 months postoperatively.

Results:

The follow-up rate was 91% (129/142). In the delayed cohort, 63% returned to competitive sport after 12 months (mean, 14 months). Few patients (n = 10) returned before 9 months. In the delayed group, 33% had a subsequent ACL injury; this was not significantly different when compared with the nondelayed group (31% rate), in which a majority (58%) returned to competitive sport before 12 months. Subsequent ACL injury rates were also similar when compared between patients who returned before and after 12 months postoperatively (33% vs 32%, respectively).

Conclusion:

At midterm follow-up, the overall rates of subsequent ACL injury were high, even for patients who delayed their return until 12 months after surgery. More research is required to identify strategies to reduce the high reinjury rate in younger athletes.

Joint movement variability during landing in patients with anterior cruciate ligament reconstruction

BACKGROUND

Rapid knee valgus and knee internal rotation motions in the initial phase of landing are the known mechanisms for anterior cruciate ligament injury, and many studies have been investigated on knee joint peak angle during landing. However, the variability in joint movement during landing has not been fully investigated. This study aimed to compare the coefficient of variation of lower extremity range of motion in patients with anterior cruciate ligament reconstruction and healthy subjects during landing.

METHODS

In this cross-sectional study, 54 patients with anterior cruciate ligament reconstruction and 44 healthy subjects were enrolled. All participants underwent six trials of single-leg hop landing for maximum safe horizontal distance. The kinematic variables were the coefficient of variation during two discrete (0.05 after initial contact and maximum knee flexion) time points for selected three-dimensional hip and knee joint range of motion. Comparisons were performed between the two groups.

RESULTS

Compared with healthy subjects, patients with anterior cruciate ligament reconstruction had greater the coefficient of variation in hip internal/external rotation range of motion (patients with anterior cruciate ligament reconstruction had 41.9%, healthy subjects had 25.5%; P=0.0018; effect size: 0.32) and knee internal/external rotation range of motion (patients with anterior cruciate ligament reconstruction had 68.4%; healthy subjects had 48.1%; P=0.0014; effect size: 0.32) for periods that spanned 0.05 s from the initial contact.

CONCLUSIONS

Patients with anterior cruciate ligament reconstruction could be disadvantageous in ability to control and adapt hip and knee joint rotations when controlling landings.

A New Rating Scale for the Rapid Evaluation of High-Level Sports Ability

Background:

Nearly half of patients with an anterior cruciate ligament (ACL) injury who have returned to sport after ACL reconstruction can return to sports activity at a competitive level, so emphasis should be focused not only on the timing of return to the sport but also on measuring the ability to participate in high-level sports activity.

Purpose:

To develop and evaluate a new, self-administered rating scale for rapid evaluation of high-level sports ability among community-level athletes who return to sports after ACL reconstruction surgery.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

We developed the new rating scale—the Knee Stability in Sports/Cutting-Pivoting Ability (KSS/CPA) scale—in 2 stages. Initially, we used a survey and roundtable discussion to achieve an expert consensus for the KSS/CPA scale from a group of independent orthopaedic experts. Next, 77 amateur athletes who underwent ACL reconstruction by a single surgeon were recruited for a background analysis of data to compare the new scale with results from the Marx activity rating scale, Tegner activity scale, International Knee Documentation Committee Subjective Knee Form, and self-assessment of overall knee function.

Results:

The KSS/CPA scale was applicable and effective for evaluating the high-level sports ability of community-level athletes who had returned to their sport after ACL reconstruction. Statistical analysis confirmed the test-retest reliability of the new rating scale (intraclass correlation coefficient, 0.85/0.84 postoperatively) as well as its internal consistency (Cronbach alpha coefficient, 0.73 preoperatively and 0.89 postoperatively), construct validity (Spearman correlation coefficient, >0.35 postoperatively), excellent discriminant validity, acceptable responsiveness, and reasonable minimal detectable change (<25).

Conclusion:

The KSS/CPA scale can act as a supplement to other clinical outcome measures for a more comprehensive evaluation of community-level athletes’ cutting-pivoting ability and knee stability.