ACL Injuries Aren't Just for Girls: The Role of Age in Predicting Pediatric ACL Injury

Unraveling sex-specific risks of knee osteoarthritis before menopause: Do sex differences start early in life?

OBJECTIVE

Sufficient evidence within the past two decades have shown that osteoarthritis (OA) has a sex-specific component. However, efforts to reveal the biological causes of this disparity have emerged more gradually. In this narrative review, we discuss anatomical differences within the knee, incidence of injuries in youth sports, and metabolic factors that present early in life (childhood and early adulthood) that can contribute to a higher risk of OA in females.

DESIGN

We compiled clinical data from multiple tissues within the knee joint-since OA is a whole joint disorder-aiming to reveal relevant factors behind the sex differences from different perspectives.

RESULTS

The data gathered in this review indicate that sex differences in articular cartilage, meniscus, and anterior cruciate ligament are detected as early as childhood and are not only explained by sex hormones. Aiming to unveil the biological causes of the uneven sex-specific risks for knee OA, we review the current knowledge of sex differences mostly in young, but also including old populations, from the perspective of (i) human anatomy in both healthy and pathological conditions, (ii) physical activity and response to injury, and (iii) metabolic signatures.

CONCLUSIONS

We propose that to close the gap in health disparities, and specifically regarding OA, we should address sex-specific anatomic, biologic, and metabolic factors at early stages in life, as a way to prevent the higher severity and incidence of OA in women later in life.

Predictors of Anterior Cruciate Ligament Tears in Adolescents and Young Adults

Background

Anterior cruciate ligament (ACL) injury in youth can lead to expensive treatment, lengthy rehabilitation, and long-term impairment. Injuries to the ACL are more common in adolescents who participate in organized sports.

Purpose

To examine whether there is an association between age, physical activity patterns, pubertal timing (Tanner stage), or body mass index (obesity/overweight status) and the risk of developing an ACL injury in youth.

Study Design

Cohort study; Level of evidence, 2.

Methods

Data from the Growing Up Today Study (GUTS), a prospective cohort study of youth throughout the United States, were used in this study. From 1996 to 2003, questionnaires were sent to GUTS participants every 12 to 18 months to assess a variety of self-reported factors; in a related 2004 questionnaire, ACL tears and other diagnoses among the participants were reported. Cox proportional hazard models were run to determine the sex-specific association of activity patterns and pubertal timing with risk of developing an ACL tear.

Results

A total of 4519 boys and 5622 girls (age: 9-15 years) were included, with 2.4% and 2.0% sustaining an ACL injury, respectively. Age was found to be a significant risk factor for ACL injury in both sexes (male: hazard ratio [HR] = 1.30 [95% CI, 1.14-1.48]; female: HR = 1.23 [95% CI, 1.10-1.38]). Mean hours per week engaged in vigorous activity was also predictive of a higher risk of ACL injury (male: HR = 1.04 [95% CI, 1.01-1.08]; female: HR = 1.10 [95% CI, 1.07-1.14]). The sports that were the most predictive of injury were running, basketball, soccer, and cheerleading/gymnastics in girls and running, football, and karate/martial arts in boys. Additionally, in boys, overweight/obese status was found to be a significant predictor of ACL injury (HR = 2.61 [95% CI, 1.60-4.26]). Furthermore, among 9- to 13-year-old girls, advanced Tanner stage was a strong predictor of injury risk (HR = 2.43 [95% CI, 1.10-5.36]).

Conclusion

Age, time engaged in vigorous activity, overweight/obese status, and advanced Tanner stage were associated with an increased risk of ACL injury in young adults and adolescents. Further research with follow-up data will help complement this study and continue to highlight the risk factors associated with ACL reconstruction in adolescents and young adults.

Anterior knee laxity is greater in athletic females who attain menarche at a younger age

PURPOSE

Females with above-average anterior knee laxity values are at increased risk of anterior cruciate ligament (ACL) injury. The purpose of this study was to examine the effects of menarche age (MA) and menarche offset on anterior knee laxity in young, physically active women.

METHODS

Anterior knee laxity (KT-2000) and menstrual characteristics (per self-report) were recorded in 686 Slovenian sportswomen from team handball, volleyball and basketball club sports (average years sport participation: 7.3 ± 3.6 years). Females were stratified into four groups based on their self-reported age at menarche: 9-11, 12, 13 and 14+ years. Anterior knee laxity was compared across MA groups using a univariate analysis of variance (ANOVA) with Bonferroni correction, with and without controlling for factors that could potentially differ between groups and influence anterior knee laxity. Females were then stratified into four groups based on the number of years they were away from their age at onset of menarche. Groups were compared using a univariate ANOVA with Bonferroni correction, with and without controlling for factors that differed between groups and could influence anterior knee laxity.

RESULTS

Anterior knee laxity was greater in females who attained menarche at 12 years of age (6.4 ± 1.5 mm) or younger (6.6 ± 1.6 mm) compared to 14 years of age or older (5.8 ± 1.2 mm) (p < 0.001; partial η2 = 0.032). Anterior knee laxity was 0.7-1.4 mm greater in females who were 5 or more years away from menarche compared to those who were within 2 years of menarche (5.8 ± 1.3 mm; p < 0.001).

CONCLUSION

Anterior knee laxity is greater in females who attained menarche at a younger age and in females who are 5 or more years postmenarche. Age of menarche represents a critical pubertal event that is easy for women to recall and may provide important insights into factors that moderate anterior knee laxity, a risk factor for ACL injury in women.

LEVEL OF EVIDENCE

Level IV.

Increased Alpha Angles and Younger Age Increase the Risk of Contralateral Femoral Acetabular Impingement Syndrome Symptom Development and Surgical Intervention: A Systematic Review

PURPOSE

To identify the preoperative risk factors associated with contralateral symptom development and surgical intervention for patients presenting with unilateral femoral acetabular impingement (FAI) syndrome.

METHODS

A literature search was performed using PubMed and Scopus computerized databases according to the 2020 Preferred Reporting Items for Systematic Meta-Analyses guidelines. Studies evaluating preoperative risk factors associated with the contralateral progression of FAI were included. Quality assessment was completed using the Methodological Index for Non-Randomized Studies criteria.

RESULTS

A total of 5 studies (n = 1,011 patients; mean age, 29.9 years) published from 2013 to 2022 met the inclusion/exclusion criteria. Mean follow-up ranged from 12 to 132 months. The overall rate of contralateral progression of symptomatic FAI ranged from 32.4% to 81%. Increased alpha angle was frequently reported factor associated with contralateral symptom progression, followed by decreased total arc of rotation, decreased internal rotation, reduced neck-shaft angle, and head-neck offset. The incidence rate of progression to contralateral surgery ranged from 15.7% to 24% of patients. Younger age was frequently reported factor associated with contralateral surgical intervention, followed by male sex, increased level of activity, and increased alpha angle.

CONCLUSIONS

Increased alpha angle and younger age were commonly reported risk factors associated with an increased risk of symptom development and surgical progression of contralateral FAI, respectively. The overall rate of contralateral progression of symptomatic FAI and the rate of progression to surgical intervention ranged up to 81% and 24%, respectively. This information may help both patients and surgeons to establish expectations regarding development of contralateral hip symptoms and possible need for surgery.

LEVEL OF EVIDENCE

Level III; systematic review of Level II-III studies.

Prevalence and Predictors of Concomitant Meniscal Surgery During Pediatric and Adolescent ACL Reconstruction: Analysis of 4729 Patients Over 20 Years at a Tertiary-Care Regional Children's Hospital

Background

The rate of concomitant meniscal procedures performed in conjunction with anterior cruciate ligament (ACL) reconstruction is increasing. Few studies have examined these procedures in high-risk pediatric cohorts.

Hypotheses

That (1) the rates of meniscal repair compared with meniscectomy would increase throughout the study period and (2) patient-related factors would be able to predict the type of meniscal operation, which would differ according to age.

Study Design

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

Methods

Natural language processing was used to extract clinical variables from notes of patients who underwent ACL reconstruction between 2000 and 2020 at a single institution. Patients were stratified to pediatric (5-13 years) and adolescent (14-19 years) cohorts. Linear regression was used to evaluate changes in the prevalence of concomitant meniscal surgery during the study period. Logistic regression was used to determine predictors of the need for and type of meniscal procedure.

Results

Of 4729 patients (mean age, 16 ± 2 years; 54.7% female) identified, 2458 patients (52%) underwent concomitant meniscal procedures (55% repair rate). The prevalence of lateral meniscal (LM) procedures increased in both pediatric and adolescent cohorts, whereas the prevalence of medial meniscal (MM) repair increased in the adolescent cohort (P = .02). In the adolescent cohort, older age was predictive of concomitant medial meniscectomy (P = .031). In the pediatric cohort, female sex was predictive of concomitant MM surgery and of undergoing lateral meniscectomy versus repair (P≤ .029). Female sex was associated with decreased odds of concomitant LM surgery in both cohorts (P≤ .018). Revision ACLR was predictive of concomitant MM surgery and of meniscectomy (medial and lateral) in the adolescent cohort (P < .001). Higher body mass index was associated with increased odds of undergoing medial meniscectomy versus repair in the pediatric cohort (P = .03).

Conclusion

More than half of the young patients who underwent ACLR had meniscal pathology warranting surgical intervention. The prevalence of MM repair compared with meniscectomy in adolescents increased throughout the study period. Patients who underwent revision ACLR were more likely to undergo concomitant meniscal surgeries, which were more often meniscectomy. Female sex had mixed effects in both the pediatric and adolescent cohorts.

Prevalence and Predictors of Concomitant Meniscal and Ligamentous Injuries Associated With ACL Surgery: An Analysis of 20 Years of ACL Reconstruction at a Tertiary Care Children's Hospital

BACKGROUND

There is an increasing rate of procedures being performed for concomitant injuries during anterior cruciate ligament (ACL) surgery. Few studies have examined risk factors for these associated injuries in young patients.

HYPOTHESIS

There are patient-related factors predictive of concomitant knee pathology that differ between age-based cohorts.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Natural language processing was used to extract clinical variables from available notes of patients undergoing ACL surgery between 2000 and 2020 at a single institution (5174 ACL surgeries; mean age, 17 ± 4 years; 53.1% female; accuracy, >98%). Patients were stratified to pediatric (5-13 years), adolescent (14-19 years), and young adult (20-35 years) cohorts. Logistic regression was used to determine predictors of concomitant injury to the menisci, medial collateral ligament (MCL), posterolateral corner (PLC), and posterior cruciate ligament (PCL).

RESULTS

Between 2000 and 2020, 54% of pediatric, 71% of adolescent, and 70% of adult patients had ≥1 concomitant soft tissue injury. In children and adolescents, increased age was consistently predictive of sustaining a concomitant injury (P < .02). Female children had increased odds of concomitant medial meniscal injury, while female adults had decreased odds (P≤ .046). Adolescent and adult female patients had decreased odds of concomitant lateral meniscal injury (P≤ .027). Female children had increased odds of injury to the MCL (P = .015), whereas female children and adolescents had decreased odds of PCL injury (P≤ .044). Adolescents undergoing revision ACL surgery had increased odds of meniscal injury (P≤ .001) and decreased odds of concomitant MCL injury (P = .028). Increased body mass index (BMI) was associated with increased odds of concomitant medial meniscal injury in all cohorts (P≤ .041), lateral meniscal injury in adults (P = .045), and PLC injury in children (P = .016). Contact injuries were associated with increased odds of MCL injury in adolescents (P = .017) and PLC injury in adolescents and adults (P < .014).

CONCLUSION

These findings support the hypothesis, as there were multiple factors that significantly affected the risk of concomitant injuries that differed between cohorts. Increased age, BMI, and contact injury history were generally associated with increased odds of sustaining a concomitant injury, whereas female sex and revision ACL surgery had mixed effects. Further studies are essential to investigate the sex-based differences in risk for concomitant injuries and to develop tailored treatment plans that minimize the risk of secondary ACL injury.

Paediatric reference anatomy for ACL reconstruction and secondary anterolateral ligament or lateral extra-articular tenodesis procedures

OBJECTIVES

For iliotibial band (ITB) lateral extra-articular tenodesis or anterolateral ligamentous/capsular reconstruction with anterior cruciate ligament reconstruction, a clear understanding of the referenced anterolateral knee anatomy is critical-especially given the risk of injury to the physis or key anterolateral structures in the paediatric population, which is at high-risk for primary and secondary anterior cruciate ligament injury. The purpose of this study was to quantitatively assess the anatomy of the knee physes, paediatric lateral collateral ligament (LCL) origin, popliteus origin and ITB tibial insertion.

METHODS

Nine paediatric cadaveric knee specimens with average age 4.2 years (range 2 months-10 years) underwent dissection to identify the LCL's and popliteus' femoral origins and the ITB's tibial insertion. Metallic marking pins demarcated precise anatomic attachment sites, and subsequent computerised tomography scans enabled quantified measurements among them.

RESULTS

LCL & Popliteus: On the femur, the popliteus origin lay consistently deep to the LCL and inserted both distally and anteriorly to the LCL, a mean distance of 4.6 mm (range 1.9-7.6; standard deviation 2.0). From the joint line, the LCL lay a mean distance of 12.5 mm proximally while the popliteus measured a mean of 8.2 mm. Both were consistently distal to the physis. The LCL was a mean distance of 4.4 mm (range 1.0-9.5) and the popliteus was a mean distance of 8.2 (range 1.7-12.5) from the physis. ITB insertion: The ITB insertion at Gerdy's tubercle had an average footprint measuring 28.2 mm² (range 10.3-58.4) and the ITB centre lay proximal to the physis in 6 specimens (mean age 4.2 years, median 2.5 years) and distal in 3 specimens (mean age 1.5 years, median 4 months). Mean distance from the footprint centre to the physis was 1.6 mm proximal (range 7.1 proximal - 2.2 distal).

CONCLUSION

This study describes relative and quantitative positions of the femoral LCL and popliteus origins and tibial ITB attachment and their respective physeal relationships. Knowledge of paediatric anterolateral knee anatomy will help guide essential future research and procedures providing extra-articular anterolateral rotatory stabilisation and may help reduce iatrogenic physeal injury risk.

LEVEL OF EVIDENCE

N/A (descriptive anatomic study).

Differences in the course of rehabilitation and outcomes for publicly insured pediatric patients after anterior cruciate ligament reconstruction

OBJECTIVE

Examine the effect of insurance type on physical therapy (PT) utilization and outcomes within pediatric and adolescent patients after anterior cruciate ligament reconstruction.

DESIGN

Multicenter retrospective cohort study.

METHODS

PT visits and functional hop test performance were extracted into a shared database. The average number of PT visits per week was assessed overall and by time period. Independent samples t-test examined the effect of insurance on PT utilization and the effect of insurance status on the odds of passing single-legged hop tests was assessed using multivariable logistic regression.

RESULTS

A total of 281 patients (15.7 ± 1.9, 42% female) were included in this analysis. Of these, 128 (45%) had public insurance. Publicly insured patients experienced a longer delay from surgery to hop test (8.3vs7.7 months, p = 0.009), attended overall fewer PT visits per week (0.92vs1.04, p = 0.005), with most of the decreased frequency occurring between weeks 7-24. Insurance status had a significant effect on the odds of passing the single leg hop test (2.72; 95%CI, 1.27-5.81).

CONCLUSION

Publicly insured patients average a lower number of weekly PT visits, experienced a longer delay from surgery to hop testing and were 2.7 times less likely to pass the single leg hop for distance test.

Sex-Specific Changes in Physical Risk Factors for Anterior Cruciate Ligament Injury by Chronological Age and Stages of Growth and Maturation From 8 to 18 Years of Age

OBJECTIVE

To critically assess the literature focused on sex-specific trajectories in physical characteristics associated with anterior cruciate ligament (ACL) injury risk by age and maturational stage.

DATA SOURCES

PubMed, CINAHL, Scopus, and SPORTDiscus databases were searched through December 2021.

STUDY SELECTION

Longitudinal and cross-sectional studies of healthy 8- to 18-year-olds, stratified by sex and age or maturation on ≥1 measure of body composition, lower extremity strength, ACL size, joint laxity, knee-joint geometry, lower extremity alignment, balance, or lower extremity biomechanics were included.

DATA EXTRACTION

Extracted data included study design, participant characteristics, maturational metrics, and outcome measures. We used random-effects meta-analyses to examine sex differences in trajectory over time. For each variable, standardized differences in means between sexes were calculated.

DATA SYNTHESIS

The search yielded 216 primary and 22 secondary articles. Less fat-free mass, leg strength, and power and greater general joint laxity were evident in girls by 8 to 10 years of age and Tanner stage I. Sex differences in body composition, strength, power, general joint laxity, and balance were more evident by 11 to 13 years of age and when transitioning from the prepubertal to pubertal stages. Sex differences in ACL size (smaller in girls), anterior knee laxity and tibiofemoral angle (greater in girls), and higher-risk biomechanics (in girls) were observed at later ages and when transitioning from the pubertal to postpubertal stages. Inconsistent study designs and data reporting limited the number of included studies.

CONCLUSIONS

Critical gaps remain in our knowledge and highlight the need to improve our understanding of the relative timing and tempo of ACL risk factor development.

Trends in Pediatric Anterior Cruciate Ligament Reconstruction: The Effect of COVID-19

CONTEXT

The number of pediatric anterior cruciate ligament reconstructions (ACLRs) occurring yearly increased almost 6-fold from 2004-2014. We find it interesting that limited recent data exist on rates of ACL injury and reconstruction in children and adolescents, especially in the context of COVID-19.

OBJECTIVE

Given the effect of the COVID-19 pandemic on youth sports seasons and the postponement of many elective surgeries, we sought to examine the changes in rates of ACLR during this period.

DESIGN

Retrospective cohort study.

SETTING

This study used the Pediatric Health Information System (PHIS) database to identify eligible patients at PHIS-participating hospitals nationwide from January 2016-June 2021, with March 1, 2020, considered the start of the COVID-19 pandemic.

PATIENTS OR OTHER PARTICIPANTS

Using Current Procedural Terminology codes, patients 18 years old and younger who underwent ACLR surgery were identified.

MAIN OUTCOME MEASURE(S)

Patient demographics and overall rates of surgery prepandemic and intrapandemic were compared. Data were analyzed using bivariate, mixed-model, and time series analyses.

RESULTS

A total of 24 843 ACLRs were identified during this time period. In total, 1853 fewer surgeries than expected were performed after March 2020 given prepandemic trends. Intrapandemic demographics revealed an increase in the proportion of patients who identified as White and with private insurance and a decrease in the proportion who identified as Black and with public insurance. Also, the proportion of ACLRs by region shifted, with more surgeries performed in the Midwest and fewer in the Northeast. In the model adjusted for hospital-level variability, only race and insurance status remained significant.

CONCLUSIONS

Based on prepandemic trends, fewer patients than projected underwent ACLR once the pandemic began, likely due to a combination of decreased rates of injury and delayed surgery.

Influence of Sex, Race/Ethnicity, and Socioeconomic Factors on Meniscal Treatment With Pediatric and Adolescent ACL Reconstruction

BACKGROUND

The rate of anterior cruciate ligament (ACL) reconstruction is increasing over time in pediatric/adolescent populations, but there is less evidence to support how concomitant meniscal procedures are changing over time. There are also less data to suggest which characteristics are associated with meniscectomy versus meniscal repair treatment.

HYPOTHESIS

Age, sex, race/ethnicity, income, and insurance type may independently affect the rate of concomitant meniscal procedures and treatment modalities in pediatric patients with ACL reconstruction.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

The Pediatric Health Information System database was queried for all patients aged ≤18 years who underwent ACL reconstruction with or without concomitant meniscal procedures from 2015 to 2019. Basic demographic data including age, sex, self-identified race/ethnicity, rural-urban commuting area code, predicted median income, and insurance status were collected. Linear regression was used to model trends and multiple logistic regression modeling was used to test for associations.

RESULTS

A total of 14,398 patients aged ≤18 years underwent ACL reconstruction during the study period, with 8337 patients (58%) having concomitant meniscal procedures with a 1.24-fold increase over 5 years. Of the concomitant meniscal treatment cohort, 41% had a meniscectomy and 59% had meniscal repair. There was a 0.82-fold change in meniscectomy and a 1.67-fold increase in meniscal repair during the study period. Male patients, older patients, Black race, living in an urban area, and those with nonprivate insurance had increased odds of undergoing a concomitant meniscal procedure (all P < .05). Patients of non-White race and those with nonprivate insurance had increased odds of having a meniscectomy versus meniscal repair (all P < .05). There were no associations detected between income bracket and the outcomes in this study.

CONCLUSION

This study shows that in pediatric and adolescent patients undergoing ACL reconstruction, there was a rise in concomitant meniscal procedures from 2015 to 2019. In addition, patients of non-White race and those with nonprivate insurance have increased odds of undergoing meniscectomy versus meniscal repair.

Epidemiology and Revision Rates of Pediatric ACL Reconstruction in New York State

BACKGROUND

There are limited epidemiologic data examining the incidence of pediatric anterior cruciate ligament reconstruction (ACLR) over the past decade.

PURPOSE

To examine statewide population trends in the incidence of ACLR in a pediatric population.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Inpatient and outpatient claims for pediatric patients who underwent ACLR between 2009 and 2017 were identified in the New York Statewide Planning and Research Cooperative System database via International Classification of Diseases (ICD), Revision 9, Clinical Modification; ICD, Revision 10, Clinical Modification and Procedural Classification System; or Current Procedural Terminology codes. New York population data for each year between 2009 and 2017 were used from the New York State Department of Health to calculate the rates of ACLR per 100,000 people aged 3 to 19 years and determine the 95% confidence limits. The rates were then stratified by age, sex, and insurance. Two-year rates of revision and contralateral ACLR were also analyzed by sex.

RESULTS

Between 2009 and 2017, 20,170 pediatric ACLRs were identified. The rates of pediatric ACLR increased steadily from 49.3 per 100,000 in 2009 (95% CI, 47.2-51.4) to a peak of 61.0 (95% CI, 58.6-63.4) in 2014 and decreased to 51.8 (95% CI, 49.6-54.1) by 2017. The age group 15 to 17 years had the highest rates of ACLR of all age groups, peaking at 198.5 (95% CI, 188.3-208.7) per 100,000. Analysis by sex showed that ACLR rates between males and females were not different. Males had a 2-year ipsilateral revision rate of 4.3%, while females had a rate of 3.3% (P = .0001). Females had a contralateral ACLR rate of 4.0%, while males had a rate of 2.6% (P = .0002).

CONCLUSION

Pediatric ACLR rates continued to rise until 2014, but there was a demonstrable decrease in rates after 2014. This decline in pediatric ACLR may point to the efficacy of injury prevention programs or changes in practice management. The high revision rate in males and high contralateral surgery rate in females can help guide patient counseling for return to play and complication risk.

CLINICAL RELEVANCE

This study showed that ACLR in pediatric patients may be decreasing in recent years. There were differences in revision and contralateral ACLR by sex.

Unique Considerations for the Pediatric Athlete During Rehabilitation and Return to Sport After Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) injuries and surgical intervention in the pediatric population have increased in the recent years. Although surgical techniques have advanced, evidence-based rehabilitation guidelines that consider all aspects of the youth athlete are currently lacking. The purpose of this commentary is to review the current evidence on unique considerations for the pediatric and adolescent population during rehabilitation and return to sport after ACL reconstruction (ACLR), with a focus on children under 18 years of age. This review revealed that returning a youth athlete to sport after ACLR requires knowledge and appreciation of various aspects of the growing athlete different from adults. In addition to postoperative precautions that contribute to a slow rehabilitation process, young athletes need additional time for strength gains. Address risk of reinjury and for contralateral injury by using neuromuscular training and rigorous return-to-sport training programs. Consider return to sport after 9 months because the reinjury rate is high in this population. A combination of time and objective measures, both quantitative and qualitative criteria, and psychological readiness should be used to assess readiness to return to sport and decrease risk of future injury. Healthcare providers should be aware of the psychosocial impact of injury on the youth athletes and refer to sport psychology when necessary.

LEVEL OF EVIDENCE

Level V.

Iliotibial Band Autograft Provides the Fastest Recovery of Knee Extensor Mechanism Function in Pediatric Anterior Cruciate Ligament Reconstruction

Iliotibial band autograft is an increasingly popular option for pediatric anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to compare recovery of knee extensor mechanism function among pediatric patients who underwent ACLR using iliotibial band (IT), hamstring tendon (HT), quadriceps tendon (QT), and patellar tendon (PT) autografts. One hundred forty-five pediatric athletes (76 female; age 15.0, range 7–21 years) with recent (3–18 months) unilateral ACLR performed drop-jump landing and 45° cutting with 3D motion capture. Knee extensor mechanism function (maximum knee flexion angle, maximum internal knee extensor moment, energy absorption at knee) during the loading phase (foot contact to peak knee flexion) was compared among graft types (20 IT, 29 HT, 39 QT, 57 PT) and sides (ACLR or contralateral) using linear mixed models with sex, age, and time since surgery as covariates. Overall, knee flexion was significantly lower on the operated vs. contralateral side for HT, QT, and PT during both tasks (p < 0.03). All graft types exhibited lower knee extensor moments and energy absorption on the operated side during both movements (p ≤ 0.001). Kinetic asymmetry was significantly lower for IT compared with QT and PT during both movements (p ≤ 0.005), and similar patterns were observed for HT vs. QT and PT (p ≤ 0.07). Asymmetry was similar between IT and HT and between QT and PT. This study found that knee extensor mechanism function recovers fastest in pediatric ACLR patients with IT autografts, followed by HT, in comparison to QT and PT, suggesting that IT is a viable option for returning young athletes to play after ACLR.