Return to Sport and Reoperation Rates in Patients Under the Age of 20 After Primary Anterior Cruciate Ligament Reconstruction: Risk Profile Comparing 3 Patient Groups Predicated Upon Skeletal Age

Management of Anterior Cruciate Ligament Tears in Skeletally Immature Patients

PURPOSE OF REVIEW

Anterior cruciate ligament (ALC) tears are increasingly common in skeletally immature patients, as more children and adolescents participate in intensive sports training and specialization at increasingly younger ages. These injuries were historically treated nonoperatively, given concerns for physeal damage and subsequent growth disturbances after traditional ACL reconstruction techniques. However, there is now sufficient data to suggest superior outcomes with operative treatment, specifically with physeal-sparing and physeal-respecting techniques. This article reviews considerations of skeletal maturity in patients with ACL tears, then discusses surgical techniques, with a focus on their unique indications and outcomes. Additional surgical adjuncts and components of postoperative rehabilitation, which may reduce retear rates, are also considered.

RECENT FINDINGS

Current research shows favorable patient-reported outcomes and high return-to-sport rates after ACL reconstruction in skeletally immature patients. Graft rupture (ACL retear) rates are low, but notably higher than in most adult populations. Historically, there has been insufficient research to comprehensively compare reconstruction techniques used in this patient population. However, thoughtful systematic reviews and multicenter prospective studies are emerging to address this deficit. Also, more recent data suggests the addition of lateral extra-articular procedures and stringent return-to-sports testing may lower retear rates. Physeal-sparing and physeal-respecting ACL reconstructions result in stabilization of the knee, while respecting the growth remaining in children or skeletally immature adolescents. Future research will be essential to compare these techniques, given that more than one may be appropriate for patients of a specific age and skeletal maturity.

Quadriceps Tendon Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients: 3-Year Clinical and Patient-Reported Outcomes

BACKGROUND

The rate of anterior cruciate ligament (ACL) rupture in active, skeletally immature patients is increasing. Although hamstring tendon autograft (HTA) was previously deemed the gold standard, recent studies have shown HTA to have a high failure rate in this high-risk population of young competitive athletes, and quadriceps tendon autograft (QTA) has yielded excellent preliminary outcomes in some studies examining this population.

PURPOSE

To evaluate 3-year clinical and patient-reported functional outcomes of primary ACL reconstruction (ACLR) with soft tissue QTA in skeletally immature patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Skeletally immature patients who underwent ACLR with a full-thickness soft tissue QTA were included. Preoperative patient and surgical data were collected. The ACLR technique was selected predicated upon skeletal age and included all-epiphyseal and complete transphyseal techniques. Patients were followed for a minimum of 2 years with successive clinical visits or were contacted via telephone. Patients who did not have minimum 2-year follow-up after 3 contact attempts via telephone were excluded. Information regarding return to sports (RTS) and concomitant or subsequent surgical procedures was collected. Pediatric International Knee Documentation Committee (Pedi-IKDC), Hospital for Special Surgery Functional Activity Brief Scale (HSS Pedi-FABS), and Single Assessment Numeric Evaluation (SANE) scores were collected.

RESULTS

Of 85 adolescent patients aged 11.1 to 17.6 years (mean age, 14.1 ± 1.2 years), 2 patients were determined to be lost to follow-up after 3 failed contact attempts. Of the patients included in this study (N = 83), 26 patients (31%) underwent all-epiphyseal and 57 patients (69%) underwent complete transphyseal ACLR. Additionally, 48 patients (58%) underwent concomitant lateral extra-articular tenodesis using the iliotibial band with a modified Lemaire technique. The mean follow-up time was 3.7 ± 1.2 years (range, 2-7 years). Twenty (24%) patients had subsequent surgical procedures, of which 3 (4%) were due to graft failures. At a mean 3-year follow-up, the mean Pedi-IKDC, HSS Pedi-FABS, and SANE scores were 90, 23, and 94 respectively; the RTS rate was 100%; and the rate of RTS at the previous level of performance was 93%.

CONCLUSION

Use of a soft tissue QTA for ALCR in a high-risk skeletally immature population of athletes resulted in excellent postoperative outcomes with low rates of graft failure and high return to sport rates.

Global overview of anterior cruciate ligament reconstruction in children and adolescents over the past 20 years: a bibliometric analysis

OBJECTIVES

The objectives of this paper is to conduct a bibliometric analysis to examine the research status and development trend of anterior cruciate ligament injury and reconstruction in children and adolescents over the past 20 years.

DESIGN

Descriptive Research.

METHODS

This study obtained information regarding studies on Anterior Cruciate Ligament Reconstruction in Children and Adolescents from the Web of Science Core Collection database. Visual and bibliometric analysis were conducted using VOSviewer, Origin 2022, Pajek64 5.18and Excel 2019. These analytic tools facilitated the analysis of various aspects, including countries/regions, institutions, authors, journals and keywords related to the research.

RESULTS

From 2003 to 2023, a total of 1328 articles were retrieved in WOS, and 637 articles were selected by two authors. The most productive institutions are Childrens Hosp Philadelphia, Kocher, ms. Their articles have the highest number of publications and citations. The American journal of sports medicine is the most frequently cited journal for articles on anterior cruciate ligament reconstruction in children and adolescents. The most common keywords used in these articles were "anterior cruciate ligament reconstruction", "injury, children, adolescent", and "skeletally immature patients".

CONCLUSIONS

This study provides valuable insights into the research focus of anterior cruciate ligament reconstruction in children and adolescents. In recent years, there has been significant attention paid to areas of "the return to sport, re-repture rate and functional recovery after anterior cruciate ligament reconstruction" in this specific population. These aspects have emerged as key directions for future research in this field.

Effect of Age and Sex on Anterior Cruciate Ligament Functional Tests Approximately 6 Months After Anterior Cruciate Ligament Reconstruction

Purpose

To examine age- and sex-related differences in postoperative functional outcomes at approximately 6 months after anterior cruciate ligament reconstruction (ACLR).

Methods

In this study, patients who underwent primary ACLR performed a series of return-to-sport functional tests at 5 to 8 months after surgery. Functional tests included strength tests (knee extensors, knee flexors, hip abductors, and hip extensors), a balance test (Y-balance composite score), and hop tests (single, triple, crossover, and 6-m timed hop tests). Limb symmetry was calculated to compare the reconstructed limb with the uninvolved limb. A 2-way multivariate analysis of covariance was used, and effect size was calculated for data analysis.

Results

A total of 176 subjects were included in this study. There were no significant interaction between age and sex on return-to-sport functional tests after ACLR. Also, no main effects of age and sex on return-to-sport functional tests were found in our data.

Conclusions

Age and sex do not significantly affect functional test performance after ACLR 6 months postoperatively.

Level of Evidence

Level III, retrospective review of prospective cohort study.

Subjective Causes for Failure to Return to Sport After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

CONTEXT

While current literature has explored the outcomes of athletes who return to sport (RTS) after anterior cruciate ligament (ACL) injuries, less is known about the outcomes of those who are unsuccessful in returning to sport.

OBJECTIVE

To determine the rate of athletes who did not RTS after primary ACL reconstruction (ACLR) and to identify the specific subjective reasons for failure to RTS.

DATA SOURCES

A comprehensive search of the PubMed/MEDLINE, Scopus, and Web of Science databases was conducted through April 2021.

STUDY SELECTION

Eligible studies included those explicitly reporting the rate of failure for RTS after ACLR as well as providing details on reasons for athletes' inability to return; 31 studies met the inclusion criteria.

STUDY DESIGN

Systematic review and meta-analysis.

LEVEL OF EVIDENCE

Level 2 to 4.

DATA EXTRACTION

The reasons for failure to RTS referred to in our study are derived from those established previously in the studies included. Data were collected on the number of athletes, mean age, mean follow-up time, type of sport played, failure to RTS rate, and specific reasons for failure to return.

RESULTS

The weighted rate of failure to RTS after ACLR was 25.5% (95% CI, 19.88-31.66). The estimated proportion of psychosocial-related reasons cited for failure to RTS was significantly greater than knee-related reasons for failure RTS (55.4% vs 44.6%, P < 0.01). The most cited reason for failure to RTS was fear of reinjury (33.0%).

CONCLUSION

This study estimates the rate of failure to RTS after ACLR to be 25.5%, with the majority of athletes citing fear of reinjury as the major deterrent for returning to sports. We highlight how factors independent of surgical outcomes may impact an athlete's ability to return to play given that the predominant reason for no RTS after ACLR was unrelated to the knee.

All-epiphyseal anterior cruciate ligament reconstruction yields superior sports performances than the trans-epiphyseal technique in skeletally immature patients: a systematic review

BACKGROUND

Anterior cruciate ligament (ACL) tears in skeletally immature patients are increasingly common. Evidence comparing the outcomes of all-epiphyseal versus trans-epiphyseal ACL reconstruction in skeletally immature patients is limited, and the current literature could benefit from a comprehensive systematic review. The present study compared all-epiphyseal versus trans-epiphyseal ACL reconstruction in skeletally immature patients. The outcomes of interest were to compare joint laxity, patient-reported outcome measures (PROMs), return to sport, and complications.

METHODS

This study was conducted according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. In November 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. No additional filters were used in the database search. All the clinical studies investigating ACL reconstruction in skeletally immature patients were accessed. Only articles that clearly stated the surgical technique (all- or trans-epiphyseal) were eligible. Only articles with a minimum of 6 months of follow-up were included. Only articles that clearly stated that surgeries were conducted in children with open physis were eligible.

RESULTS

Data from 1489 patients (1493 procedures) were collected, of which 32% (490 of 1489 patients) were female. The mean length of follow-up was 46.6 months. The mean age of the patients was 12.7 years. No difference was found in joint laxity (Table 3): positive pivot shift (P = 0.4), positive Lachman test (P = 0.3), and mean arthrometer laxity (P = 0.1). No difference was found in PROMs (Table 4): International Knee Documentation Committee (IKDC) (P = 0.3), Lysholm (P = 0.4), and Tegner (P = 0.7). The trans-epiphyseal technique was associated with a greater rate of patients unable to return to sports (1% versus 7%, P = 0.0001) and with a longer time to return to sports (7.7 versus 8.6 months, P = 0.01). Though the trans-epiphyseal technique was associated with a lower rate of return to sport, this difference was not statistically significant (P = 0.8). No difference was evidenced in the rate of patients who had reduced their league or level of sports activity (P = 0.6) or in the rate of patients who had returned to their previous league or level of sports activity (P = 0.7). No difference was found in the rate of complication: re-tear (P = 0.8), reoperation (P = 0.7), increased laxity (P = 0.9), and persistent instability sensation (P = 0.3).

CONCLUSION

Trans-epiphyseal ACL reconstruction was associated with a greater rate of patients unable to return to sport and with a longer time to return to sport compared with the all-epiphyseal technique in skeletally immature patients. Level of evidence Level III, systematic review.

Improved Patient-reported Outcomes in Patients Aged 16 and Younger at Two Years After Anterior Cruciate Ligament Reconstruction Despite Relatively High Rates of Reinjury and Repeat Surgery

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) in adolescent patients, particularly those aged 16 and under, are increasingly common procedure that lacks robust clinical and patient-reported outcome (PRO) data. The purpose of this study was to report 2-year PROs of patients receiving ACLR aged 16 or younger using the single assessment numerical evaluation (SANE) and knee injury and osteoarthritis outcome score (KOOS). Secondary aims included characterizing treatment characteristics, return to sport (RTS), and clinical outcomes.

METHODS

The institutional PRO database was queried for patients receiving ACLR from 2009 to 2020. Patients aged older than 16, revision procedures, concomitant ligament repairs/reconstructions, and patients without full outcome data at 2 years were excluded. Outcomes over 2 years after ACLR included SANE, KOOS, reinjuries, reoperations, and time to RTS.

RESULTS

A total of 98 patients were included with an average age of 15.0 years. Most patients were females (77.6%). Bone-tendon-bone autograft (69.4%) was the most used. Average RTS was 8.7 months (range: 4.8 to 24.0 mo), with 90% of patients eventually returning to sport. A total of 23 patients (23.5%) experienced a reinjury and 24.5% (n = 24) underwent reoperation. Timing to RTS was not associated with reinjury, but patients who returned between 9.5 and 13.7 months did not sustain reinjuries. Mean KOOS and SANE scores at 2 years were 87.1 and 89.1, respectively, with an average improvement of +18.4 and +22.9, respectively. Change in KOOS was negatively impacted by reinjury to the anterior cruciate ligament graft and reoperation (anterior cruciate ligament failure: +10.0 vs 19.3, P = 0.081, respectively; reoperation: +13.2 vs +20.1, P = 0.051, respectively), though these did not reach statistical significance.

CONCLUSION

Patients experienced improved SANE and KOOS scores after ACLR. Rates of reinjury and reoperation were relatively high and negatively impacted PRO scores but were not associated with the timing of RTS. Adolescent patients should be counseled regarding the risk of subsequent ipsilateral and contralateral knee injury after ACLR.

LEVEL OF EVIDENCE

Level IV-case series.

Primary anterior cruciate ligament repair: Current concepts

The renewed interest in ACL repair over the last two decades stems from advances in modern arthroscopic techniques and clinical studies that have provided evidence that the ACL can reliably heal, and patients can return to sport at a comparable rate to ACL reconstruction patients. The ability to maintain and utilize native ACL tissue, with proprioceptive capabilities, and the smaller drill tunnels needed to repair an ACL leads to an overall less invasive procedure and improved early rehabilitation. Additionally, repair avoids a variety of comorbidities associated with autograft harvest. This current concept review details modern techniques of ACL repair and their current studies, a review on the use of biologic enhancement in ACL repair, and other considerations to appropriately integrate ACL repair into the sports medicine orthopaedic surgeon's practice.

Risk Factors for Ipsilateral Versus Contralateral Reinjury After ACL Reconstruction in Athletes: A Systematic Review and Meta-analysis

Background

Anterior cruciate ligament (ACL) reinjury after ACL reconstruction (ACLR) can occur on the ipsilateral or contralateral side. Limited evidence exists regarding the difference between the incidence of reinjury to either knee, which is important in developing interventions to prevent ACL reinjury.

Purpose

To compare the reinjury rate of the ACL on the ipsilateral side versus the contralateral side in athletes after ACLR and investigate the risk factors that may cause different reinjury rates between the sides.

Study Design

Systematic review; Level of evidence, 4.

Methods

A systematic review was performed based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies that involved ACL reinjury in athletes after ACLR were reviewed. Considering several risk factors, including age and sex, a comparison of ACL reinjury incidence on the ipsilateral and contralateral sides was performed using a meta-analysis.

Results

Of the 17 selected studies, 3 were found to be at high risk of bias, and thus, 14 (n = 3424 participants) studies were included in the meta-analysis. In this athletic population, the contralateral ACL had a significantly higher rupture rate than the ipsilateral graft (risk ratio [RR], 1.41; P < .0001). Female athletes were found to have a greater risk of ACL reinjury on the contralateral versus the ipsilateral side (RR, 1.65; P = .0005), but different results were found in male athletes. (RR, 0.81; P = .21). There was no statistical difference in the incidence rate of ACL reinjury to either side in adolescent athletes (RR, 1.15; P = .28).

Conclusion

The contralateral ACL was more vulnerable to reinjury than the ipsilateral side in athletes after ACLR. Female athletes were more likely to reinjure their contralateral native ACL, while the same trend was not found in their male counterparts. The reinjury rate was comparable in both knees in adolescent athletes.

Greater self-efficacy, psychological readiness and return to sport amongst paediatric patients compared with adolescents and young adults, 8 and 12 months after ACL reconstruction

PURPOSE

The purpose of this study was to evaluate differences in rehabilitation-specific outcomes between paediatric patients, adolescents and young adults within the first 2 years after anterior cruciate ligament (ACL) reconstruction. A further aim was to determine whether patient age was associated with an increased risk of not achieving symmetrical muscle function within the first 2 years after ACL reconstruction.

METHODS

The patient data in the present study were extracted from the rehabilitation outcome registry, Project ACL. Patients aged 11-25 years registered for primary ACL reconstruction with a hamstring tendon autograft between April 1, 2013 and November 23, 2020 were included. A total of 691 patients met the inclusion criteria and were included in the study; 41 paediatric patients (females 11-13, males 11-15 years), 347 adolescents (females 14-19, males 16-19 years) and 303 young adults (females 20-25, males 20-25 years).

RESULTS

The comparison between groups revealed that 70% of paediatric patients, 39% of adolescents and 35% of young adults had returned to knee-strenuous sport at 8 months and that 90% of paediatric patients, 71% of adolescents and 62% of young adults had returned to sport at 12 months. Paediatric patients also reported higher scores compared with both the other patient groups on the Knee Self-Efficacy Scale (K-SES) and the Anterior Cruciate Ligament Return to Sport after Injury scale (ACL-RSI) at 8 and 12 months.

CONCLUSIONS

A larger proportion of paediatric patients had returned to sport compared with adolescents and young adults 8 and 12 months after ACL reconstruction. Paediatric patients also reported higher self-efficacy and greater psychological readiness to return to sport at 8 and 12 months than the other two groups. No differences in terms of muscle function tests when comparing paediatric patients, adolescents and young adults were found.

LEVEL OF EVIDENCE

II.

Functional Rehabilitation of Anterior Cruciate Ligament Tear in the Pediatric Population: A Comprehensive Review

Pediatric sports injuries are a growing concern due to increased youth participation in sports. Effective rehabilitation strategies are essential for ensuring optimal recovery, restoring knee function, and preventing long-term consequences. This research aims to explore and evaluate various functional rehabilitation approaches tailored to pediatric anterior cruciate ligament (ACL) tear injuries. Functional rehabilitation of ACL tears in pediatric sports injuries is an important area of research due to the unique considerations and challenges that arise when treating ACL injuries in young athletes. Over the last 20 years, there has been a well-documented uptick in ACL injuries among pediatric populations. This rise can be attributed to the growing involvement of the younger population in competitive sports, as well as heightened awareness regarding sports-linked injuries. This study highlights the importance of early surgical reconstruction in children to enable a quick return to sports and prevent long-term cartilage and meniscal damage resulting from instability. The use of physeal-sparing ACL reconstruction techniques, particularly hamstring autografts, is recommended for favorable clinical outcomes while minimizing growth disturbances. This study offers valuable insights for healthcare professionals and researchers, serving as a reference to guide optimal approaches in managing pediatric ACL injuries and achieving successful results in this field.

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.

Anterior Cruciate Ligament Tears in the Adolescent Population: Injury Demographics and Risk of Reinjury Among High School Athletes

BACKGROUND

The incidence of anterior cruciate ligament (ACL) injuries is increasing among the adolescent population with a peak occurring in the high school age range.

PURPOSE

To characterize recent epidemiologic trends of ACL injuries, ACL reconstruction (ACLR), and retear rates in high school adolescents based on age, participating sport, and mechanism of injury.

STUDY DESIGN

Retrospective case series.

METHODS

A prospectively maintained institutional database was retrospectively reviewed for all patients 18 or younger who underwent primary ACLR between 2015 and 2020. Odds ratios were calculated for baseline patient characteristics and their association with risk of retear. Multivariate regression analysis was also performed to identify the relationship between retear and specific categorical variables.

RESULTS

A total of 482 patients were included, with a mean follow-up time of 13.0 ± 11.8 months. Patients were an average age of 16.1 ± 1.3 years old (range: 13 to 18 y). Initial presentation of ACL injuries in high school athletes often occurred at 16 years old regardless of the sport played. Based on age, high school freshmen and seniors are found to have an increased risk of ACL retear. One hundred three patients (21.6%) completed at least 2 or more years of follow-up after ACLR. Of these patients, 38.8% received a bone-tendon-bone (BTB) autograft, 36.9% hamstring autograft, 14.6% quadriceps tendon autograft, and 3.9% received hamstring allograft or other graft (eg, tibialis anterior and BTB allograft), respectively. There were 25 ipsilateral ACL retears that occurred in the patient cohort (5.2%). Thirteen (52%) of retears were females. Football and soccer were the most common sports played by patients with a retear of the ipsilateral knee (31.8% and 27.3%, respectively). Patients who were 13 to 14 or 18 years old ( P = 0.009 and 0.035, respectively) or who received a tibialis anterior/BTB allograft ( P = 0.002) were found to have increased risk of ACL retear compared with other age groups. When evaluating by sex, female soccer players had a greater risk of retear compared with male soccer players ( P = 0.007). When adjusting for multiple variables, (including age, sex, body mass index, primary reconstruction graft choice, sport, and length of follow-up), the odds of ipsilateral retear in patients who received hamstring autograft ( P = 0.02), sustained a contralateral ACL tear ( P = 0 .04), or a contact injury ( P = 0.01) were increased.

CONCLUSION

Initial presentation of ACL injuries in high school athletes often occurs at 16 years old regardless of the sport played. Based on age, high school freshmen and seniors are found to have an increased risk of ACL retear. However, the overall rate of ACL retear in high school athletes of all ages is low. Patients who underwent ACLR with hamstring tendon autograft had a greater risk of retear compared with other graft types. Female soccer players also had a greater risk of ACL retear. High school athletes must take caution when in the early high school years (underclassman) and more senior years (upperclassman), as susceptibility for ACL retears is elevated.

LEVEL OF EVIDENCE

Level IV.

Risk Factors for Revision or Rerupture After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

BACKGROUND

The rerupture or need for revision after anterior cruciate ligament reconstruction (ACLR) is a serious complication. Preventive strategies that target the early identification of risk factors are important to reduce the incidence of additional surgery.

PURPOSE

To perform a systematic review and meta-analysis to investigate risk factors for revision or rerupture after ACLR.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

Literature searches were performed in PubMed, Embase, and Web of Science from database inception to November 2021 and updated in January 2022. Quantitative, original studies reporting potential adjusted risk factors were included. Odds ratios (ORs) were calculated for potential risk factors.

RESULTS

A total of 71 studies across 13 countries with a total sample size of 629,120 met the inclusion criteria. Fifteen factors were associated with an increase in the risk of revision or rerupture after ACLR: male sex (OR, 1.27; 95% CI, 1.14-1.41), younger age (OR, 1.07; 95% CI, 1.05-1.08), lower body mass index (BMI) (OR, 1.03; 95% CI, 1.00-1.06), family history (OR, 2.47; 95% CI, 1.50-4.08), White race (OR, 1.32; 95% CI, 1.08-1.60), higher posterolateral tibial slope (OR, 1.15; 95% CI, 1.05-1.26), preoperative high-grade anterior knee laxity (OR, 2.30; 95% CI, 1.46-3.64), higher baseline Marx activity level (OR, 1.07; 95% CI, 1.02-1.13), return to a high activity level/sport (OR, 2.03; 95% CI, 1.15-3.57), an ACLR within less than a year after injury (OR, 2.05; 95% CI, 1.81-2.32), a concomitant medial collateral ligament (MCL) injury (OR, 1.62; 95% CI, 1.31-2.00), an anteromedial portal or transportal technique (OR, 1.36; 95% CI, 1.22-1.51), hamstring tendon (HT) autografts (vs bone-patellar tendon-bone [BPTB] autografts) (OR, 1.60; 95% CI, 1.40-1.82), allografts (OR, 2.63; 95% CI, 1.65-4.19), and smaller graft diameter (OR, 1.21; 95% CI, 1.05-1.38). The other factors failed to show an association with an increased risk of revision or rerupture after ACLR.

CONCLUSION

Male sex, younger age, lower BMI, family history, White race, higher posterolateral tibial slope, preoperative high-grade anterior knee laxity, higher baseline Marx activity level, return to a high activity level/sport, an ACLR within less than a year from injury, a concomitant MCL injury, an anteromedial portal or transportal technique, HT autografts (vs BPTB autografts), allografts, and smaller graft diameter may increase the risk of revision or rerupture after ACLR. Raising awareness and implementing effective preventions/interventions for risk factors are priorities for clinical practitioners to reduce the incidence of revision or rerupture after ACLR.

A Modified Lemaire Lateral Extra-articular Tenodesis in High-Risk Adolescents Undergoing Anterior Cruciate Ligament Reconstruction With Quadriceps Tendon Autograft: 2-Year Clinical Outcomes

BACKGROUND

The incidence of anterior cruciate ligament (ACL) reconstruction (ACLR) in children and adolescents has increased significantly, and many such patients are at increased risk for ACL retear. Lateral extra-articular tenodesis (LET) may be performed in conjunction with ACLR to reduce the risk of ACL retear.

PURPOSE

To evaluate the 2-year clinical outcomes of ACLR with soft tissue quadriceps tendon (QUAD) autograft performed with a concomitant LET using a modified Lemaire technique in skeletally immature patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A consecutive series of adolescent patients who underwent QUAD autograft ACLR and LET with a minimum of 2 years of follow-up data were analyzed retrospectively. ACLR techniques, including all-epiphyseal and complete transphyseal, were indicated based on skeletal age. Outcome measures included return to sports, concomitant or subsequent surgical procedures, and multiple patient-reported outcome measures, including Single Assessment Numeric Evaluation (SANE), Pediatric International Knee Documentation Committee (Pedi-IKDC), and Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) scores.

RESULTS

The final cohort included 49 consecutive adolescent patients aged 11 to 16 years (mean, 14.2 ± 1 years) with a minimum follow-up of 2 years. One patient was lost to follow-up. Of the patients included in the study (N = 48; 27 male, 21 female), 98% participated in high-risk competitive sports. Two (4%) patients were undergoing revision ACLR. Thirty-eight (79%) patients underwent complete transphyseal, and 10 (21%) patients underwent all-epiphyseal ACLR. Sixteen (33%) patients had subsequent surgical procedures, including 5 contralateral ACLR, 4 meniscal surgery, 4 QUAD autograft scar revision, 4 irrigation and debridement (2 patients, 2 each), and 3 hardware removal (2 for hemi-epiphysiodesis and 1 tibial socket button removal) procedures. The rate of graft rupture was 0%. At a mean follow-up of 3.4 ± 1.2 years (range, 2-7 range), the mean SANE score was 93, the mean Pedi-IKDC score was 89, and the mean HSS Pedi-FABS score was 23. The return-to-sports rate was 100%.

CONCLUSION

An LET performed concomitantly with an ACLR is safe and should be considered as a concomitant procedure for adolescent patients with nonmodifiable risk factors who are at high risk of retear.

Preoperative Risk Factors for Subsequent Ipsilateral ACL Revision Surgery After an ACL Restoration Procedure

BACKGROUND

Anterior cruciate ligament (ACL) revision surgery is challenging for both patients and surgeons. Understanding the risk factors for failure after bridge-enhanced ACL restoration (BEAR) may help with patient selection for ACL restoration versus ACL reconstruction.

PURPOSE

To identify the preoperative risk factors for ACL revision surgery within the first 2 years after BEAR.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Data from the prospective BEAR I, II, and III trials were used to determine the preoperative risk factors for ACL revision surgery. All patients with a complete ACL tear (aged 13-47 years, depending on the trial), who met all other inclusion/exclusion criteria and underwent a primary BEAR procedure within 30 to 50 days from the injury (dependent on the trial), were included. Demographic data (age, sex, body mass index), baseline patient-reported outcomes (International Knee Documentation Committee [IKDC] subjective score, Marx activity score), preoperative imaging results (ACL stump length, notch size, tibial slope), and intraoperative findings (knee hyperextension, meniscal status) were evaluated to determine their contribution to the risk of ipsilateral ACL revision surgery.

RESULTS

A total of 123 patients, with a median age of 17.6 years (interquartile range, 16-23 years), including 67 (54%) female patients, met study criteria. Overall, 18 (15%) patients required ACL revision surgery in the first 2 years after the BEAR procedure. On bivariate analyses, younger age (P = .011), having a contact injury at the time of the initial tear (P = .048), and increased medial tibial slope (MTS; P = .029) were associated with a higher risk of ipsilateral revision surgery. Multivariable logistic regression analyses identified 2 independent predictors of revision: patient age and MTS. The odds of ipsilateral revision surgery were decreased by 32% for each 1-year increase in age (odds ratio, 0.684 [95% CI, 0.517-0.905]; P = .008) and increased by 28% for each 1° increase in MTS (odds ratio, 1.280 [95% CI, 1.024-1.601]; P = .030). Sex, baseline IKDC or Marx score, knee hyperextension, and meniscal status were not significant predictors of revision.

CONCLUSION

Younger age and higher MTS were predictors of ipsilateral ACL revision surgery after the BEAR procedure. Younger patients with higher tibial slopes should be aware of the increased risk for revision surgery when deciding to undergo ACL restoration.

Physeal-sparing ACL reconstruction provides better knee laxity restoration but similar clinical outcomes to partial transphyseal and complete transphyseal approaches in the pediatric population: a systematic review and meta-analysis

PURPOSE

The aim of this meta-analysis was to evaluate complete transphyseal (CTP), partial transphyseal (PTP), and physeal-sparing (PS) techniques for anterior cruciate ligament (ACL) reconstruction.

METHODS

A systematic literature search of the PubMed, Web of Science, Cochrane Library, and Scopus literature databases was performed on 10.05.2021. All human studies evaluating the outcomes of CTP, PTP, and PS techniques were included. The influence of the selected approach was evaluated in terms of rates of retears, return to previous level of sport competition, IKDC subjective and objective scores, Lysholm score, rate of normal Lachman and pivot-shift tests, limb length discrepancy, and hip-knee angle (HKA) deviation. Risk of bias and quality of evidence were assessed following the Downs and Black checklist.

RESULTS

Forty-nine out of 425 retrieved studies (3260 patients) met the inclusion criteria. The results of the meta-analysis comparing CTP, PTP, and PS approaches for ACL reconstruction in the under 20-year-old population showed a significant difference in terms of differential laxity (CTP 1.98 mm, PTP 1.69 mm, PS 0.22 mm, p < 0.001). No significant differences were seen in terms of growth malalignment, rate of normal Lachman and pivot-shift tests, and rate of normal/quasi-normal IKDC objective score.

CONCLUSIONS

The present meta-analysis found overall similar results with the three ACL reconstruction approaches. The PS technique showed better results in terms of knee laxity than the PTP and CTP approaches, but this did not lead to a significant difference in terms of subjective and objective scores. No clear superiority of one technique over the others was found with respect to re-ruptures, growth disturbances, and axial deviations. While the argument for avoiding growth malalignment does not seem to be a crucial point, the PS technique should be the preferred approach in a young population to ensure knee laxity restoration.

LEVEL OF EVIDENCE

Level III.

Risk of reoperation after primary anterior cruciate ligament reconstruction in children and adolescents

OBJECTIVE

To examine the incidence and risk factors of any-cause reoperation after primary ACLR in children and adolescents.

DESIGN

Retrospective Cohort.

SETTING

Electronic medical records from a large tertiary care, single institution integrated healthcare delivery system.

PATIENTS

Patients were under the age of 18 years and had anterior cruciate ligament reconstruction. They were excluded if they had a multi-ligamentous knee injury or <1 year follow-up.

INTERVENTIONS

Patients were further identified to have undergone a subsequent knee operation ipsilaterally or contralateral ACLR.

MAIN OUTCOME MEASURES

The rate of any-cause reoperation was our primary outcome measure.

RESULTS

The median age was 16. There were 208 females (53.9%) and 178 males (46.1%) included. The median follow-up was 25 months with a minimum of 12 months (interquartile range: 16.0, 46.0). The rate of any-cause reoperation was 34.7%. There was no statistically significant difference between those who underwent reoperation versus those who did not undergo reoperation relative to age, sex, BMI, graft type, or the presence of concomitant meniscal injury. The rates of ipsilateral ACLR and contralateral ACLR at any time during the study period was 8.0% and 10.9% respectively. There was no statistically significant difference for rate of reoperation between graft types, between various concomitant injuries, between those who underwent meniscus repair or no repair.

CONCLUSIONS

This study reflects a 34.7% rate of a subsequent knee operation after ACLR in patients younger than 18 years. These findings can be used to inform pediatric patients undergoing primary ACLR on their risk of returning to the operating room.

Lower rate of acceptable knee function in adolescents compared with young adults five years after acl reconstruction: results from the swedish national knee ligament register

Background

The number of studies with a large cohort of patients that primarily focus on patient-reported outcomes after ACL reconstruction in children and adolescents is limited. The purpose of the present study was to determine whether patient age affects the proportion of patients that achieve a patient-acceptable symptom state (PASS) on the Knee injury and Osteoarthritis Outcome Score (KOOS) subscales one, two, five and 10 years after an ACL reconstruction.

Methods

The patient data in the present study were extracted from the Swedish National Knee Ligament Register (SNKLR). Patients aged between five and 35 years that underwent a primary ACL reconstruction between 1 January 2005 and 31 December 2017 and had completed the KOOS questionnaire at the one-, two-, five- or 10-year follow-up were included. A total of 2,848 patients met the inclusion criteria and were included in the study; 47 paediatric patients (females 5–13, males 5–15 years), 522 adolescents (females 14–19, males 16–19 years) and 2,279 young adults (females 20–35, males 20–35 years). The results from the KOOS were presented as the mean and 95% confidence interval (CI) for the mean. For comparisons between groups, the chi-square test was used for non-ordered categorical variables. For pairwise comparisons between groups, Fisher’s exact test (2-sided) was used for dichotomous variables. All the statistical analyses was set at 5%.

Results

Adolescents reported a significantly lower score than young adults on the KOOS4 at the two- (68.4 vs. 72.1; P < 0.05), five- (69.8 vs. 76.0; P < 0.05) and 10-year follow-ups (69.8 vs. 78.2; P < 0.05). Moreover, a significantly smaller proportion of adolescents achieved a PASS on each of the KOOS subscales when compared with young adults at the five-year follow-up (Symptoms: 83.3% vs. 91.6%; Pain: 42.9% vs. 55.3%; Function in daily living: 31.4% vs. 41.1%; Function in sports and recreational activities: 42.3% vs. 55.7%; Knee-related quality of life: 50.0% vs. 65.0%; P < 0.05).

Conclusions

A significantly smaller proportion of adolescents achieved a PASS on each of the KOOS subscales when compared with young adults five years after ACL reconstruction. The results of the present study provide important information for physicians and physiotherapists treating young patients after an ACL injury and they can aid in providing realistic expectations in terms of the mid- and long-term outcomes.

Level of evidence

Prospective Observational Register/Cohort Study, Level II.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05727-6.

Lateral extra-articular tenodesis and anterior cruciate ligament reconstruction in young patients: clinical results and return to sport

Lateral extra-articular tenodesis (L.E.T.) have been proposed to reduce the tibia's anterior translation and internal rotation in concomitant to Anterior cruciate ligament (A.C.L.) reconstruction. Recent studies show that the addition of L.E.T. to A.C.L. reconstruction results in a statistically significant reduction in graft failure. The purpose of the present study was to evaluate the clinical outcomes, complications, and rate of return to preinjury sports level in pediatric patients who underwent combined A.C.L. reconstruction with L.E.T. at a minimum 2-year follow-up. The authors retrospectively evaluated 42 pediatric patients at high risk of graft failure who experienced ACLR connected to L.E.T. IKDC and Tegner-Lysholm Knee Scores Scale were used to assess clinical outcomes, and the Tegner Activity Scale to evaluate the return to sport. No graft failure or subsequent surgery related to A.C.L. reconstruction occurred. Furthermore, 88% of patients returned to the sport. Satisfactory clinical results were obtained on a short and medium-term follow-up. These findings help to consider this procedure for active adolescents at a high risk of graft failure to enhance A.C.L. reconstruction.

Paediatric Anterior Cruciate Ligament (ACL) Injuries: Current Concepts Review

BACKGROUND

Over the past two decades, there has been a documented increase in paediatric ACL injuries because of a rise in younger age sports participation at the competitive level, awareness about sports-related injuries, and advanced imaging modalities.

METHODS

A PubMed electronic database search was done, which revealed 1366 hits over the last five years (2016 - 2020). Finally, 37 articles that contributed to new findings were included. This review was conducted based on predefined research questions.

RESULTS AND CONCLUSION

Early surgical reconstruction is recommended in children due to the increasing demand for early return to sports and to prevent the instability that can lead to progressive cartilage and meniscal damage. With the evolution of several "physeal sparing" ACL reconstruction (ACLR) techniques, a favorable clinical outcome with less growth disturbance is achievable. Although different autograft options are available, hamstring autografts are most commonly preferred. A specific pattern of a bone bruise not extending into the metaphysis, and lateral meniscus tears are the most common associated injuries. Following paediatric ACLR, complications like graft rupture and contralateral ACL injuries are two to three folds higher than with adult ACLR. Unprepared early return to sports is one of the reasons for increased complication rates in children; thus, clearance criteria for return to sports need to be standardized, and early return to sports (< 9 months post ACLR) should be avoided. Neuromuscular training protocols are recommended to minimize complications like graft ruptures.

High variability and lack of standardization in the evaluation of return to sport after ACL reconstruction: a systematic review

PURPOSE

Return to sport (RTS) after ACL reconstruction (ACLR) has been recognized as an important outcome, which is associated with success of the surgery. This study aimed to assess the methods used to determine return to sport after ACLR in the published literature, report on variability of methods and evaluate their strength in establishing accurate RTS data.

METHODS

Electronic databases (PubMed, Cochrane Library and Embase) were searched via a defined search strategy with no limits, to identify relevant studies from January 2008 to December 2020 for inclusion in the review. Defined eligibility criteria included studies specifically measuring and reporting on return to sport after ACLR with a clear methodology. Each included study was assessed for the definition of successful RTS, successful return to pre-injury level of sport and for methods used to determine RTS.

RESULTS

One hundred and seventy-one studies were included. Of the included studies, six studies (4%) were level of evidence 1 and seventy-two studies (42%) were level of evidence 4. Forty-one studies (24%) reported on return to a specific sport and 130 studies (76%) reported on return to multiple sports or general sport. Sixteen studies (9%) reported on RTS in the pediatric population, 36 (21%) in the adult population and 119 (70%) reported on a mixed-aged population. The most commonly used definition of successful RTS was return to the same sport (44 of 125 studies, 35%). The most common method used to determine RTS was a non-validated study-specific questionnaire (73 studies, 43%), which was administered in various ways to the patients. Time of RTS assessment was variable and ranged between 6 months and 27 years post-surgery.

CONCLUSION

This review demonstrates high variability in defining, evaluating and reporting RTS following ACLR. The findings of this study reveal low reliability and unproven validity of methods used to evaluate RTS and highlight the challenges in interpreting and using RTS data reported in literature.

LEVEL OF EVIDENCE

IV.

The top 100 most impactful articles on the anterior cruciate ligament: An altmetric analysis of online media

Objectives:

To identify the top 100 most impactful anterior cruciate ligament articles in online media as measured by the Altmetric Attention Score and compare their characteristics to the most-cited anterior cruciate ligament articles in the scientific literature.

Methods:

The Altmetric database was queried to identify all published articles pertaining to the anterior cruciate ligament. The search yielded 9445 articles, which were stratified by highest to lowest Altmetric Attention Score. The top 100 articles were included. Collected data included article type, article topic, journal name, and online mentions in news, blogs, Twitter, Facebook, Wikipedia, and other sources. The geographic origin of each article was also determined based on the institutional affiliation of the first author.

Results:

Altmetric Attention Score of the top 100 anterior cruciate ligament articles ranged from 109 to 2193 (median 172.0, interquartile range 137.5–271.5). Of the 100 articles, 65 were published in three journals: American Journal of Sports Medicine, British Journal of Sports Medicine, and Journal of Orthopaedic & Sports Physical Therapy. The most prevalent article type was original research (60%), followed by systematic review/meta-analysis (18%). The most prevalent article topic was rehabilitation and return to play after anterior cruciate ligament reconstruction (22%), followed by epidemiology/risk factors (16%), injury prevention (14%), and biomechanics of anterior cruciate ligament injuries (14%). Of the top 100 articles, 54% were American, 31% were European, and 15% were published in other countries outside of the United States and Europe.

Conclusion:

This study used Altmetric Attention Score to identify the 100 most engaged anterior cruciate ligament articles in online media. The characteristics of these articles differed substantially from the most-cited anterior cruciate ligament articles in the literature with regard to article type, article topic, geographic origin, and publication journal. These findings suggest that alternative metrics measure distinct components of anterior cruciate ligament article engagement and add an important dimension to understanding the overall impact of published research on the anterior cruciate ligament.

Over-the-top Anterior Cruciate Ligament (ACL) reconstruction plus lateral plasty with hamstrings in high-school athletes: Results at 10 years

BACKGROUND

Anterior Cruciate Ligament (ACL) injuries have grown in adolescent population in the last decades, and if surgical reconstruction resulted safe in the short term, its impact in the long term is still unclear. The purpose of this study was to assess the long-term risk of failure, the rate of contralateral injury and the clinical reported outcomes in a cohort of high-school athletes after ACL reconstruction.

METHODS

54 consecutive patients (mean age 16.3 ± 1.4 years) underwent ACL reconstruction with a single-bundle plus lateral plasty hamstring technique between May 2006 and July 2009. The number of subsequent ipsilateral reoperations and contralateral ACL reconstruction, Lhysolm, KOOS, VAS for pain and Tegner Activity Level was determined at a minimum follow-up of 10 years.

RESULTS

Ipsilateral ACL revision was performed in 8 (3.4%) patients, contralateral ACL reconstruction in 11 (21.1%). The average Lysholm score was 95.1 ± 9.2. The average KOOS was 96.5 ± 6.3 for the Pain subscale, 92.2 ± 9.0 for the Symptom subscale, 99.2 ± 1.8 for the ADL subscale, 94.1 ± 10.1 for the Sport subscale and 91.8 ± 14.5 for the Quality-of-life subscale. The average VAS for pain during activity was 1.7 ± 2.3. 90% returned to sport, 15% decreased the activity level, 61% of patients were still involved in sport, 35% at the same pre-injury level.

CONCLUSION

At long-term, single-bundle hamstring ACL-R plus lateral-plasty in a cohort of high school athletes resulted to have a comparable graft failure rate and contralateral ACL injury with other surgical techniques.

Clinical Outcomes and Postoperative Complications After All-Epiphyseal Double-Bundle ACL Reconstruction for Skeletally Immature Patients

Background

The treatment strategy for pediatric anterior cruciate ligament (ACL) tears, especially in patients with open physes, remains controversial.

Purpose

To assess clinical outcomes and postoperative complications after all-epiphyseal double-bundle ACL (DB-ACL) reconstruction for patients with open physes.

Study Design

Cohort study; Level of evidence, 3.

Methods

Included were 102 patients aged ≤15 years who underwent ACL reconstruction at a single institution and had a minimum of 2 years of follow-up. Of these patients, 18 had undergone all-epiphyseal DB-ACL reconstruction (mean age, 12.4 ± 1.2 year) and 84 had undergone conventional DB-ACL reconstruction (mean age, 14.1 ± 0.9 year). The outcomes of the all-epiphyseal group were compared with those of the conventional group. Objective clinical outcomes included KT-1000 arthrometer measurements of side-to-side difference in anterior tibial translation, Lachman test grade, and pivot-shift test grade. Radiographic angular deformity (defined as >3° of the side-to-side difference in femorotibial angle) and incidence of second ACL injury were also compared.

Results

The postoperative side-to-side difference in laxity significantly improved from 6.1 ± 2.4 to 0.6 ± 0.9 mm in the all-epiphyseal group (P = .001), and postoperative laxity was similar to that of the conventional group (0.4 ± 0.8 mm; P = .518). A Lachman grade 1 positive result was observed in 20% of the all-epiphyseal group and 3% of the conventional group (P = .042), and a pivot-shift grade 1 positive result was observed in 22% of the all-epiphyseal group and 4% of the conventional group (P = .074). A total of 4 patients (26.7%) in the all-epiphyseal group and 4 (6.1%) in the conventional group demonstrated angular deformity (P = .035). The incidence of postoperative ipsilateral ACL tear was 16.7% in the all-epiphyseal group and 23.8% in the conventional group (P = .757). The incidence of contralateral ACL tear was 11.1% in the all-epiphyseal group and 14.3% in the conventional group (P ≥ .999).

Conclusion

All-epiphyseal DB-ACL reconstruction for skeletally immature patients achieved satisfactory clinical outcomes compared with conventional DB-ACL reconstruction. The incidence of ipsilateral graft rupture was relatively high in both groups. The all-epiphyseal group had a significantly higher incidence of angular deformity.

Treatment Decisions in Pediatric Sports Medicine: Do Personal and Professional Bias Affect Decision-Making?

Background:

Personal and professional biases can affect decision-making regarding important issues in pediatric sports medicine. Gaining insight into the opinions of health care professionals who specialize in pediatric sports medicine will provide information that may be useful for directing ongoing research in this field.

Hypothesis:

It was hypothesized that surgeons would demonstrate bias toward early surgical intervention versus nonsurgeons. In addition, it was hypothesized that youth sports medicine professionals who were parents of a child with a previous major sports injury or concussion would be less likely to allow their child to play American tackle football or return to football after a concussion.

Study Design:

Cross-sectional study.

Methods:

An online survey was provided to the active members of the Pediatric Research in Sports Medicine Society. We used both professional background information and responses to questions related to personal experiences with youth sports injuries to determine potential factors associated with underlying biases. Survey responses among subgroups were compared using the Fisher exact test. The Pearson correlation coefficient was used to evaluate years in practice versus opioid use.

Results:

Of the survey participants, 62.5% were pediatric surgeons, and 37.5% represented different nonsurgical youth sports medicine professions. Surgeons were less likely than nonsurgeons to agree to allow their child to return to football after sustaining a concussion and completing a concussion protocol (48% vs 76%, P = .013). Surgeons were more likely than nonsurgeons to agree to both elective shoulder stabilization after a first-time dislocation and elective drilling of a stable knee osteochondritis dissecans (OCD) before nonoperative treatment (41% vs 10%, P = .003 and 52% vs 23%, P = .013, respectively). Those who reported having a child with a concussion history were more likely to support him or her returning to football after a concussion (65% vs 33%, P = .026).

Conclusion:

Surgeons were more likely to favor elective shoulder-stabilization surgery after a first-time dislocation and drilling of a stable knee OCD instead of nonoperative management. Personal experience of having a child who sustained a major sports injury or concussion did not demonstrate a bias against participation in football or return to football after a concussion.

Adolescents Have Twice the Revision Rate of Young Adults After ACL Reconstruction With Hamstring Tendon Autograft: A Study From the Swedish National Knee Ligament Registry

Background:

Previous studies have identified young age as a risk factor for anterior cruciate ligament (ACL) revision. However, few studies have looked separately at pediatric patients and adolescents with regard to outcomes after ACL reconstruction.

Purpose:

To determine whether patient age at ACL reconstruction affects the risk of undergoing revision surgery in young patients.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

This study was based on data from the Swedish National Knee Ligament Registry. Patients aged 5 to 35 years who underwent a primary ACL reconstruction with a hamstring tendon autograft between January 1, 2005, and December 31, 2015, were included. The cohort was stratified into different age groups of pediatric patients, adolescents, and young adults to estimate patients with open, recently closed, and closed epiphyses, respectively. The primary endpoint was ACL revision. A multivariable Cox regression model was used to assess the ACL revision rate. The results were expressed as hazard ratios (HRs) and 95% CIs.

Results:

A total of 36,274 ACL reconstructions were registered during the study period. Of these, 2848 patients were included in the study: 47 pediatric patients (mean age, 13.6 years; range, 9-15 years), 522 adolescents (mean age, 17.4; range, 14-19 years), and 2279 young adults (mean age, 27.0; range, 20-35 years). A total of 31 patients (1.1%) underwent ACL revision within 2 years (0 pediatric patients, 9 adolescents [1.7%], and 22 young adults [1.0%]) and a total of 53 patients (2.6%) underwent ACL revision within 5 years (2 pediatric patients [6.9%], 15 adolescents [3.9%], and 36 young adults [2.2%]). The adolescent age group had a 1.91 times higher rate of ACL revision compared with the young adults (HR = 1.91 [95% CI, 1.13-3.21]; P = .015). There were no differences in revision rates between the pediatric age group and the young adults (HR = 2.93 [95% CI, 0.88-9.79]; P = .081).

Conclusion:

Adolescents had almost twice the rate of revision ACL reconstruction compared with young adults.

Optimizing outcomes of ACL surgery-Is autograft reconstruction the only reasonable option?

Anterior cruciate ligament (ACL) injuries occur at a high frequency in the United States with approximately 400,000 ACL reconstructions being performed each year. While ACL reconstruction is our current gold standard of treatment, it does not restore joint motion, or prevent the premature development of posttraumatic osteoarthritis (PTOA) in many patients. Thus, new treatments for an ACL injury, which are less invasive and minimize patient morbidity, including cartilage damage, are highly desirable. We have used a tissue-engineered approach to stimulate ligament healing, to improve upon current treatment options. In this review, we describe and discuss our work moving a tissue engineering strategy from the concept to bench, preclinical, clinical trials and ultimately FDA 510(k) de Novo approval, providing clinicians and patients with a viable alternative to ACL reconstruction.

Stenotic Intercondylar Notch as a Risk Factor for Physeal-Sparing ACL Reconstruction Failure: A Case-Control Study

Identifying risk factors is crucial for developing strategies that minimize reinjury after anterior cruciate ligament reconstruction (ACLR). This study aims to determine whether certain features of intercondylar notch geometry are associated with failure of physeal-sparing ACLRs in skeletally immature athletes.

Knee strength outcomes in adolescents by age and sex during late-stage rehabilitation after anterior cruciate ligament reconstruction

OBJECTIVE

To determine if knee strength differences exist according to age group and sex among adolescents during late-stage anterior cruciate ligament reconstruction (ACLR) rehabilitation.

DESIGN

Retrospective cohort study.

METHODS

Consecutive patients who had undergone ACLR with a hamstring autograft completed isokinetic knee strength assessment. Patients were categorized into early (ages 11-14 years) and middle (ages 15-17 years) adolescence. A two-way MANOVA was used to examine strength differences according to age group and sex.

RESULTS

144 patients were included in the analysis (56.9% females, age = 15.3 ± 1.5 years; days since surgery = 228.2 ± 41.2). Differences in quadriceps peak torque were identified between age groups on the involved (p = 0.001) and uninvolved limbs (p < 0.001), however, no differences in quadriceps peak torque were found between age groups when normalized to body mass (p = 0.16-0.49). Differences between groups according to sex were identified for each strength outcome (p < 0.01), with decreased normalized quadriceps (12-13%) and hamstring (13-16%) peak torque for females. No interactions between age group and sex were noted, F(8, 133) = 1.48, p = 0.17.

CONCLUSION

Early adolescents produced less quadriceps and hamstring peak torque compared to middle adolescents after ACLR. No differences were found between age groups when normalized to body mass.

Anterior Cruciate Ligament Reconstruction and Lateral Plasty in High-Risk Young Adolescents: Revisions, Subjective Evaluation, and the Role of Surgical Timing on Meniscal Preservation

BACKGROUND

In adolescents, the rate of meniscal injury at the time of anterior cruciate ligament (ACL) reconstruction, the rate of ACL graft revision, and clinical outcomes has not yet been investigated.

HYPOTHESIS

In patients younger than 16 years, the rate of meniscal injuries at the time of ACL reconstruction increases with time from injury. The mid-term revision rate and reoperation rate after ACL reconstruction with hamstrings and lateral tenodesis are lower than those reported in literature for isolate ACL reconstruction.

STUDY DESIGN

Case series.

LEVEL OF EVIDENCE

Level 4.

METHODS

Patients younger than 16 years who underwent ACL reconstruction with hamstring and lateral tenodesis, with a follow-up ≥2 years were included. The number of meniscal lesions was stratified according to the delay between injury-to-surgery (<3, 3-12, >12 months). All reoperations, Lysholm score, Knee Injury and Osteoarthritis Outcome Score subscales for pain (at rest and during activity), and return to sport were collected.

RESULTS

A total of 151 patients (mean age 14.8 ± 1.2 years) were included. Patients undergoing surgery at <3 months after injury had a lower meniscal injury rate (36%) than those treated at 3 to 12 months (55%) and >12 months (63%) after injury (P = 0.04). Medial meniscal lesions were more likely to be repaired when surgery was performed <3 months after injury (91%). Subjective follow-up data were available for 132 patients, and 19 were lost to follow-up. At 6.0 ± 2.6 years, 6% of patients underwent ACL revision; 1 of 20 (5%) patients with posterior tibial slope ≥12° and 4 of 45 (9%) patients with Tegner level ≥8. Nine new meniscal procedures were performed; 19% of repaired menisci underwent meniscectomy. Good or excellent Lysholm score was reported by 88% of patients; 56% of patients with concurrent lateral meniscectomy had pain during activity, 91% returned to sport, and 79% were still participating at final follow-up.

CONCLUSION

Patients younger than 16 years undergoing ACL reconstruction within 3 months from injury had the lowest rate of meniscal injuries. ACL reconstruction with lateral tenodesis had low revision rate (6%) and good or excellent clinical outcomes in 88% of young adolescents.

CLINICAL RELEVANCE

Sport physicians should be aware that adolescent patients undergoing ACL reconstruction within 3 months after injury have the lowest rate of meniscal injuries; the mid-term revision rate of ACL reconstruction with lateral plasty is lower than 10% and the patients' perceived outcomes are good with almost all patients returning to sport activity.

High Specialization among Female Youth Soccer Players Is Associated with an Increased Likelihood of Serious Injury

PURPOSE

This study aimed to assess the associations between serious injury (≥3-month time loss) and level of specialization among high-level female soccer players and to compare the specialization and college commitment ages of female youth soccer players to Division I college and professional soccer athletes.

METHODS

Youth, college, and professional female soccer players in the United States playing in the top league at each level were recruited to complete an anonymous online survey. The survey collected information about player demographics, soccer specialization and training patterns, history of serious injuries from soccer, and perceptions surrounding soccer specialization. Comparisons between groups were performed using two-sample t-tests, χ2 analyses, and multiple logistic regression models controlling for differences in age. A P value of less than 0.05 was set as significant.

RESULTS

A total of 1,018 (767 youth, 251 college/professional) athletes completed the survey. Serious injuries affected 23.6% of youth and 51.4% of college/professional athletes. Anterior cruciate ligament tears were more prevalent in college/professional players compared with youth athletes (18.3% vs 4.0%; P < 0.001). Highly specialized youth athletes (66.5%) were more likely to have sustained a serious injury from soccer compared with athletes with low specialization (odds ratio, 2.28 (1.38-3.92); P = 0.008) but not moderate specialization (odds ratio, 1.37 (0.83-2.27); P = 0.43). A higher proportion of youth athletes specialized at a young age (≤10 yr) compared with college/professional players (44.2% vs 25.9%; P < 0.001).

CONCLUSIONS

High specialization in female youth soccer players is associated with an increased likelihood of sustaining a serious injury. Current youth soccer players are specializing earlier and committing to play college soccer at a younger age compared with when current college and professional players did.

Risk Factors for Failure After Anterior Cruciate Ligament Reconstruction in a Pediatric Population: A Prediction Algorithm

Background:

Anterior cruciate ligament reconstruction (ACLR) in pediatric patients is becoming increasingly common. There is growing yet limited literature on the risk factors for revision in this demographic.

Purpose:

To (1) determine the rate of pediatric revision ACLR in a nationally representative sample, (2) ascertain the associated patient- and injury-specific risk factors for revision ACLR, and (3) examine the differences in the rate and risks of revision ACLR between pediatric and adult patients.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

The PearlDiver patient record database was used to identify adult patients (age ≥20 years) and pediatric patients (age <20 years) who underwent primary ACLR between 2010 and 2015. At 5 years postoperatively, the risk of revision ACLR was compared between the adult and pediatric groups. ACLR to the contralateral side was also compared. Multivariate logistic regression was used to determine the significant risk factors for revision ACLR and the overall reoperation rates in pediatric and adult patients; from these risk factors, an algorithm was developed to predict the risk of revision ACLR in pediatric patients.

Results:

Included were 2055 pediatric patients, 1778 adult patients aged 20 to 29 years, and 1646 adult patients aged 30 to 39 years who underwent ACLR. At 5 years postoperatively, pediatric patients faced a higher risk of revision surgery when compared with adults (18.0 % vs 9.2% [adults 20-29 years] and 7.1% [adults 30-39 years]; P < .0001), with significantly decreased survivorship of the index ACLR (P < .0001; log-rank test). Pediatric patients were also at higher risk of undergoing contralateral ACLR as compared with adults (5.8% vs 1.6% [adults 20-29 years] and 1.9% [adults 30-39 years]; P < .0001). Among the pediatric cohort, boys (odds ratio [OR], 0.78; 95% CI, 0.63-0.96; P = .0204) and patients >14 years old (OR, 0.62; 95% CI, 0.45-0.86; P = .0035) had a decreased risk of overall reoperation; patients undergoing concurrent meniscal repair (OR, 1.84; 95% CI, 1.43-2.38; P < .0001) or meniscectomy (OR, 2.20; 95% CI, 1.72-2.82; P < .0001) had an increased risk of revision surgery. According to the risk algorithm, the highest probability for revision ACLR was in girls <15 years old with concomitant meniscal and medial collateral ligament injury (36% risk of revision).

Conclusion:

As compared with adults, pediatric patients had an increased likelihood of revision ACLR, contralateral ACLR, and meniscal reoperation within 5 years of an index ACLR. Families of pediatric patients—especially female patients, younger patients, and those with concomitant medial collateral ligament and meniscal injuries—should be counseled on such risks.

Effectiveness of thicker hamstring or patella tendon grafts to reduce graft failure rate in anterior cruciate ligament reconstruction in young patients

PURPOSE

The purpose of this study was to determine the anterior cruciate ligament reconstruction (ACLR) failure rate in young patients utilizing the New Zealand (NZ) anterior cruciate ligament (ACL) Registry. The hypothesis was that the ACLR rupture rate would be lower for thicker hamstring graft and bone patellar tendon bone (BPB) grafts in comparison to the classic hamstring technique. The ACLR failure rate was assessed according to graft type and patients' sex.

METHODS

The NZ ACL registry was utilized to identify all patients aged 20 years or younger at the time of surgery who were skeletally mature and had a minimum 2-year follow-up. Graft ruptures, defined as an ACL revision, were identified according to graft type (traditional 4 strands hamstring semitendinosus and gracilis, 4 strands semitendinosus, 5-6 strands semitendinosus and gracilis, 7-8 strands semitendinosus and gracilis, bone-patella-bone graft).

RESULTS

Nine-hundred and ninety-two patients were included. At a mean follow-up of 38 months, 52 cases of graft rupture were recorded, (overall failure rate: 5.2%). The failure rate was not statistically influenced by the graft diameter. Patients with a thinner graft (< 8 mm-196 patients) had a similar failure rate (6%) to patients with a thicker graft (8 mm or more-485 patients) (6.2%). There was a lower failure rate in the BPB group (3.1%) versus all hamstrings group (6%) (ns). Finally, BPB in females had a lower failure rate than all hamstring constructs together (0% versus 5.1%; p = 0.023) CONCLUSION: In a young population traditional four-strand hamstring grafts, multiple strand configurations or BPB ACLR, whatever their size (> or < 8 mm), showed no significant difference in the failure rate in the NZ ACL registry. Female patients who had an ACL reconstruction with BPB graft had a significant lower failure rate than patients who had a hamstring graft.

LEVEL OF EVIDENCE

III.

Secondary Injuries After Pediatric Anterior Cruciate Ligament Reconstruction: A Systematic Review With Quantitative Analysis

BACKGROUND

In the skeletally mature anterior cruciate ligament (ACL) reconstruction population, patients aged <25 years are at significantly increased risk of graft failure and injury to the contralateral ACL. Skeletal immaturity often affects graft selection and reconstruction technique.

PURPOSE

To examine the incidence of ipsilateral graft failure and contralateral ACL injury in the skeletally immature patient population.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

Using the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines, we reviewed all literature that involved ACL reconstruction performed on skeletally immature patients between May 1976 and May 2019. Patient demographics, surgical technique, and the prevalence of ipsilateral graft failure or subsequent contralateral ACL injury were recorded. Ipsilateral, contralateral, and secondary ACL injuries were then compared between sexes via chi-square tests.

RESULTS

A total of 24 articles (1254 children; 1258 knees) met inclusion criteria for analysis. Ipsilateral graft failures occurred in 105 of 1258 patients (8.3%), and there were no statistically significant sex differences in the prevalence of graft failures (female, 9.7%; male patients, 7.1%; P = .14). The prevalence of contralateral ACL injury was significantly greater in female (29/129; 22.5%) than male (18/206; 8.7%; P = .0004) patients in the 9 studies that reported contralateral injury. Skeletally immature female patients were at significantly increased risk of contralateral ACL injury (odds ratio = 3.0; P = .0006) when compared with their male counterparts.

CONCLUSION

In the literature to date, 1 in 3 female skeletally immature patients experienced an ipsilateral graft failure or contralateral ACL injury. Regardless of sex, the 24% prevalence of secondary injury after pediatric ACL reconstruction is almost identical to previously published secondary injury rates in skeletally mature patients <25 years old. As such, skeletal maturity alone does not seem to be a determinant of secondary injury; however, there is a clear need to improve postoperative rehabilitation, activity progression, and return-to-play testing to allow a safe return to sports that protects the long-term health of the reconstructed and contralateral limbs, especially for female patients.

Mid-term outcomes of anterior cruciate ligament reconstruction across age groups: A national database study

Background

The purpose of this study was to examine the impact of age on complication risk after anterior cruciate ligament reconstruction.

Methods

The TriNetX research database was retrospectively queried for patients undergoing primary arthroscopic ACL reconstruction. Univariate logistic regression was performed to evaluate the risk of complication by age group.

Results

A total of 21,449 patients were included in the study. Patients ≥61 years old demonstrated significantly higher rates of repeat reconstruction. Rates of postoperative opioid related disorders and surgical site infection varied by age.

Conclusion

For patients undergoing ACL reconstruction, increasing age is associated with increased risk of developing opioid related disorders, and repeat reconstruction.

Healthy Pediatric Athletes Have Significant Baseline Limb Asymmetries on Common Return-to-Sport Physical Performance Tests

Background:

Return to sport (RTS) after anterior cruciate ligament (ACL) reconstruction in children is associated with a much higher risk (∼30%) of subsequent ACL injury than in adults. Most RTS testing protocols use a limb symmetry index (LSI) ≥90% on physical performance tests (PPTs) to assess an athlete’s readiness for sport. This assumes that, in a healthy state, the physical performances across both lower extremities are and should be equal.

Purpose:

To determine the prevalence of limb asymmetries >10% in the uninjured pediatric population on common PPTs as well as to explore the relationship between athlete variables, limb preference, and LSI values.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

This study included healthy volunteers (N = 100) evenly distributed between the ages of 6 and 18 years (mean age, 11.7 ± 3.6 years; 52% female). Participants performed 9 common PPTs. For analysis, we developed a composite score for each limb by averaging trials. We then calculated the LSI for each test. Univariable and multivariable linear regression analyses were performed to assess the relationship between athlete variables (age, sex, height, and weight) and LSI for each PPT.

Results:

Instances of poor baseline limb symmetry (<90% LSI) were common across all PPTs. The single-leg timed hop had the highest percentage of participants, with LSI ≥90% at 73%, while the stork on a Bosu ball had the lowest percentage at 23%. After adjusting for age, female sex showed a significant association with LSI for the stork test (P = .010) and the quadrant hop–counterclockwise (P = .021). Additionally, after adjusting for sex, increasing age showed a significant association with LSI for the stork test (P < .001), single-leg squat on a Bosu ball (P = .010), quadrant hop–clockwise (P = .016), and quadrant hop–counterclockwise (P = .009).

Conclusion:

The majority of healthy athletes 18 years and younger demonstrated significant (<90%) limb asymmetries. Limb symmetry was not consistently affected by participant age or sex, and the effect sizes of these relationships were small. These findings should encourage clinicians and coaches to exercise caution in using the LSI as an isolated measure of RTS readiness after injury in pediatric athletes.

Beighton Score, Tibial Slope, Tibial Subluxation, Quadriceps Circumference Difference, and Family History Are Risk Factors for Anterior Cruciate Ligament Graft Failure: A Retrospective Comparison of Primary and Revision Anterior Cruciate Ligament Reconstructions

PURPOSE

To assess patient history, physical examination findings, magnetic resonance imaging (MRI) and 3-dimensional computed tomographic (3D CT) measurements of those with anterior cruciate ligament (ACL) graft failure compared with primary ACL tear patients to better discern risk factors for ACL graft failure.

METHODS

We performed a retrospective review comparing patients who underwent revision ACL reconstruction (ACLR) with a primary ACLR group with minimum 1-year follow-up. Preoperative history, examination, and imaging data were collected and compared. Measurements were made on MRI, plain radiographs, and 3D CT. Inclusion criteria were patients who underwent primary ACLR by a single surgeon at a single center with minimum 1-year follow-up or ACL graft failure with revision ACLR performed by the same surgeon.

RESULTS

A total of 109 primary ACLR patients, mean age 33.7 years (range 15 to 71), enrolled between July 2016 and July 2018 and 90 revision ACLR patients, mean age 32.9 years (range 16 to 65), were included. The revision ACLR group had increased Beighton score (4 versus 0; P < .001) and greater side-to-side differences in quadricep circumference (2 versus 0 cm; P < .001) compared with the primary ACLR group. A family history of ACL tear was significantly more likely in the revision group (47.8% versus 16.5%; P < .001). The revision group exhibited significantly increased lateral posterior tibial slope (7.9° versus 6.2°), anterolateral tibial subluxation (7.1 versus 4.9 mm), and anteromedial tibia subluxation (2.7 versus 0.5 mm; all P < .005). In the revision group, femoral tunnel malposition occurred in 66.7% in the deep-shallow position and 33.3% in the high-low position. The rate of tibial tunnel malposition was 9.7% from medial to lateral and 54.2% from anterior to posterior. Fifty-six patients (77.8%) had tunnel malposition in ≥2 positions. Allograft tissue was used for the index ACLR in 28% in the revision group compared with 14.7% in the primary group.

CONCLUSION

Beighton score, quadriceps circumference side-to-side difference, family history of ACL tear, lateral posterior tibial slope, anterolateral tibial subluxation, and anteromedial tibia subluxation were all significantly different between primary and revision ACLR groups. In addition, there was a high rate of tunnel malposition in the revision ACLR group.

Failure Rates of Autograft and Allograft ACL Reconstruction in Patients 19 Years of Age and Younger: A Systematic Review and Meta-Analysis

BACKGROUND

Graft choice for pediatric anterior cruciate ligament reconstruction (ACLR) is determined by several factors. There is limited information on the use and outcomes of allograft ACLR in pediatric patients. The purpose of this systematic review and meta-analysis was to quantify reported failure rates of allograft versus autograft ACLR in patients ≤19 years of age with ≥2 years of follow-up. We hypothesized that there would be higher rates of failure for allograft compared with autograft ACLR in this population.

METHODS

PubMed/MEDLINE and Embase databases were systematically searched for literature regarding allograft and autograft ACLR in pediatric/adolescent patients. Articles were included if they described a cohort of patients with average age of ≤19 years, had a minimum of 2 years of follow-up, described graft failure as an outcome, and had a Level of Evidence grade of I to III. Qualitative review and quantitative meta-analysis were performed to compare graft failure rates. A random-effects model was created to compare failure events in patients receiving allograft versus autograft in a pairwise fashion. Data analysis was completed using RevMan 5.3 software (The Cochrane Collaboration).

RESULTS

The database search identified 1,604 studies; 203 full-text articles were assessed for eligibility. Fourteen studies met the inclusion criteria for qualitative review; 5 studies were included for quantitative meta-analysis. Bone-patellar tendon-bone (BTB) represented 58.2% (n = 1,012) of the autografts, and hamstring grafts represented 41.8% (n = 727). Hybrid allografts (autograft + supplemental allograft) represented 12.8% (n = 18) of all allograft ACLRs (n = 141). The unweighted, pooled failure rate for each graft type was 8.5% for BTB, 16.6% for hamstring, and 25.5% for allograft. Allografts were significantly more likely than autografts to result in graft failure (odds ratio, 3.87; 95% confidence interval, 2.24 to 6.69).

CONCLUSIONS

Allograft ACLR in pediatric and adolescent patients should be used judiciously, as existing studies revealed a significantly higher failure rate for allograft compared with autograft ACLR in this patient population. Additional studies are needed to improve the understanding of variables associated with the high ACLR failure rate among pediatric and adolescent patients.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Open Full-Thickness Quadriceps Tendon Autograft Harvest With Repair for Anterior Cruciate Ligament Reconstruction

Historically, one of the most common graft choices for anterior cruciate ligament (ACL) reconstruction in the pediatric population has been the hamstring autograft. Although pediatric ACL reconstructions with a hamstring autograft have allowed a majority of children and adolescents to return to athletics, it has been reported that anywhere between 6% and 38% of these patients will go on to experience subsequent graft rupture. The quadriceps tendon autograft is an alternative to the hamstring tendon autograft that demonstrates superior preliminary outcomes, and we currently recommend it for skeletally immature patients undergoing primary and revision ACL reconstruction. This paper aims to describe our technique for an open full-thickness quadriceps tendon harvest with repair.

Single Sport Specialization in the Skeletally Immature Athlete: Current Concepts

Youth sport participation patterns have drastically changed over the past two decades. Increasingly, young individuals are specializing in single sport while skeletally immature. Sport specialization in the growing athlete has profound effects on performance, short- and long-term injury risks, and joint health. Evidence continues to mount as the detrimental effects of this trend on the immature athlete. The knee, shoulder, and elbow of these young athletes are particularly affected by this emphasis on skill-based sporting activity as opposed to generalized fitness and participation. An understanding of the epidemiology of sport participation, particularly financial impacts, and the effects on elite sport performance are critical so that the clinician can effectively educate athletes, parents, and coaches.

Transphyseal Anterior Cruciate Ligament Reconstruction Using Hybrid Transtibial Femoral Drilling and a Quadriceps Tendon Autograft

Significant controversy exists regarding the optimal surgical technique for anterior cruciate ligament (ACL) reconstruction in adolescents with 1 to 3 years of skeletal growth remaining. Graft choice and physeal injury remain primary concerns given significantly elevated rates of failure of hamstring autograft reconstructions in this population, as well as risks of leg-length discrepancy and growth axis deviation. Traditional (more vertical) transtibial drilling of the femoral tunnel can reduce risks of physeal injury but has been shown to have less accuracy restoring the native femoral ACL footprint and associated incomplete knee stabilization. On the other hand, anteromedial and outside-in drilling yields improvements in the tunnel location and biomechanics but at the cost of a more oblique trajectory and greater risk of physeal injury. A hybrid transtibial pin technique using a Pathfinder guide facilitates femoral drilling with the "best of both worlds," allowing for reproduction of the native ACL footprint and a more physeal-respecting femoral tunnel. When combined with an all-soft tissue quadriceps tendon autograft and suspensory fixation, the hybrid transtibial method yields a reliable, safe, and robust construct with promising results for the young athlete. We describe our preferred graft harvest, tunnel drilling, and fixation techniques to minimize physeal risks and optimize outcomes.

All-epiphyseal anterior cruciate ligament reconstruction produces good functional outcomes and low complication rates in pediatric patients: a systematic review

PURPOSE

To assess the literature on indications, outcomes, and complications in pediatric patients undergoing all-epiphyseal (AE) anterior cruciate ligament reconstruction (ACLR).

METHODS

PubMed, Medline, and Embase were searched for literature evaluating AE ACLR in pediatric patients. All included studies were assessed for quality using the Methodological Index for Non-Randomized Studies (MINORS). Descriptive statistics are presented where applicable.

RESULTS

Overall, 17 studies comprising 545 patients, with a mean age of 12.0 ± 1.2 (range 8-19) met the inclusion criteria. The graft choices in this systematic review included hamstring tendon autografts (75.4%, n = 403), quadriceps tendon autograft (6.2%, n = 33), Achilles tendon allograft (3.6%, n = 19) and posterior tibialis tendon allograft in one patient (0.2%, n = 1). Time of return-to-sport ranged from 8 to 22 months. Postoperative subjective IKDC scores were above 90 points. The rate of return-to-sport after AE ACLR was 93.2% (n = 219/235) and 77.9% (n = 142/183) of patients returned to sport at pre-injury level. The overall complication rate was 9.8% (n = 53/545) with the most common complication being ACL re-rupture (5.0%; n = 27/545). Only 1.5% (n = 8/545) of patients demonstrated growth disturbances.

CONCLUSION

Overall, the AE ACLR technique can achieve good postoperative functional outcomes while notably minimizing the incidence of primary issue of physeal disruption and potential associated leg-length discrepancies. AE ACLR should be considered in pediatric patients with at least 2 years of skeletal growth remaining based on radiographic bone age to minimize the impact of growth-related complications.

LEVEL OF EVIDENCE

IV (Systematic Review of Level III and IV evidence).

Anterior Cruciate Ligament Re-tear and Revision Reconstruction in the Skeletally Immature Athlete

PURPOSE OF REVIEW

With an increase in high-demand sporting activity, the rate of pediatric and adolescent anterior cruciate ligament (ACL) reconstruction is increasing. Yet, the failure rates after reconstruction are much higher than the adult population. The purpose of this paper is to understand failure rates, reasons for graft failure, and strategies for successful revision surgery.

RECENT FINDINGS

A complete understanding of the failure etiology is essential for the clinician treating this population prior to revision. This begins with an assessment of post-operative patient compliance and sporting activity. Surgical technique must then be scrutinized for non-anatomic tunnel placement and poor graft size/type. Concurrent bony deformity must also be addressed including lower extremity valgus alignment and tibial slope abnormalities. Meniscus and chondral injury must be aggressively treated. Furthermore, imaging must be examined to look for missed posterolateral corner injury. Lateral extra-articular tenodesis (in the setting of ligamentous laxity or rotational instability) may be also indicated as well. The surgeon can then choose a graft type and surgical technique that optimizes outcome and respects skeletal growth. Prior to surgical intervention, the clinician must also counsel patients in regard to the guarded prognosis and outcomes in this setting. Prolonged rehabilitation protocols/return-to-play timing as well as sporting activity modification in the post-operative period after revision are critical. There is limited literature on revision ACL reconstruction in the skeletally immature athlete. An understanding of all the risk factors for failure is essential in order to achieve treatment success.

Bridge-Enhanced Anterior Cruciate Ligament Repair Is Not Inferior to Autograft Anterior Cruciate Ligament Reconstruction at 2 Years: Results of a Prospective Randomized Clinical Trial

BACKGROUND

Preclinical studies suggest that for complete midsubstance anterior cruciate ligament (ACL) injuries, a suture repair of the ACL augmented with a protein implant placed in the gap between the torn ends (bridge-enhanced ACL repair [BEAR]) may be a viable alternative to ACL reconstruction (ACLR).

HYPOTHESIS

We hypothesized that patients treated with BEAR would have a noninferior patient-reported outcomes (International Knee Documentation Committee [IKDC] Subjective Score; prespecified noninferiority margin, -11.5 points) and instrumented anteroposterior (AP) knee laxity (prespecified noninferiority margin, +2-mm side-to-side difference) and superior muscle strength at 2 years after surgery when compared with patients who underwent ACLR with autograft.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

One hundred patients (median age, 17 years; median preoperative Marx activity score, 16) with complete midsubstance ACL injuries were enrolled and underwent surgery within 45 days of injury. Patients were randomly assigned to receive either BEAR (n = 65) or autograft ACLR (n = 35 [33 with quadrupled semitendinosus-gracilis and 2 with bone-patellar tendon-bone]). Outcomes-including the IKDC Subjective Score, the side-to-side difference in instrumented AP knee laxity, and muscle strength-were assessed at 2 years by an independent examiner blinded to the procedure. Patients were unblinded after their 2-year visit.

RESULTS

In total, 96% of the patients returned for 2-year follow-up. Noninferiority criteria were met for both the IKDC Subjective Score (BEAR, 88.9 points; ACLR, 84.8 points; mean difference, 4.1 points [95% CI, -1.5 to 9.7]) and the side-to-side difference in AP knee laxity (BEAR, 1.61 mm; ACLR, 1.77 mm; mean difference, -0.15 mm [95% CI, -1.48 to 1.17]). The BEAR group had a significantly higher mean hamstring muscle strength index than the ACLR group at 2 years (98.2% vs 63.2%; P < .001). In addition, 14% of the BEAR group and 6% of the ACLR group had a reinjury that required a second ipsilateral ACL surgical procedure (P = .32). Furthermore, the 8 patients who converted from BEAR to ACLR in the study period and returned for the 2-year postoperative visit had similar primary outcomes to patients who had a single ipsilateral ACL procedure.

CONCLUSION

BEAR resulted in noninferior patient-reported outcomes and AP knee laxity and superior hamstring muscle strength when compared with autograft ACLR at 2-year follow-up in a young and active cohort. These promising results suggest that longer-term studies of this technique are justified.

REGISTRATION

NCT02664545 (ClinicalTrials.gov identifier).

Over the top anterior cruciate ligament reconstruction in patients with open physes: a long-term follow-up study

INTRODUCTION

Anterior cruciate ligament (ACL) rupture in skeletally immature athletes is becoming an injury with increasing incidence. Choices of treatment are still debated, including conservative management vs. various surgical techniques. The lack of long-term reports has been highlighted in the literature.

AIM

To evaluate long-term results of ACL reconstructions performed in skeletally immature patients using the Over the Top technique with lateral extra-articular tenodesis.

METHODS

Retrospective study. All surgeries performed by same surgeon. A total of 42 patients included. All patients had pre-operative radiological studies.

SUBJECTS

30 males and 12 females. Average age: 12.5 years (range 11-14 years). Average follow-up: 96.1 months. Clinical evaluation: Pedi-IKDC, Tegner-Lysholm, KT-1000 and plain radiographs. Standardized rehabilitation protocol.

RESULTS

No instability or leg length discrepancy was recorded. Average pre-operative Tegner-Lysholm and Pedi-IKDC scores were 55 and 40, respectively, with a score of 94.8 (p < 0.05) and 94.78, respectively, at final follow-up (p < 0.05). Average post-operative (1 month) Tegner-Lysholm score: 75 (range: 62-79). Median post-operative Tegner activity: 8. Mean side-to-side (KT-1000): 1.2 mm. A total of 22 patients could go back to pre-injury sport activity, with an average rehabilitation of 7.3 months.

DISCUSSION

A significant number of cases were included in our structured standardized study and follow-up. Functional scores were excellent overall. Excellent results are testified by a final achievement of 22 patients going back to pre-injury sport activity, which is in keeping with the literature. Our experience exhibited a low complication rate and no metalwork failure. We correlate our results to the use of the Over the Top technique with lateral extra-articular tenodesis.

CONCLUSION

The studied procedure seems to be an excellent option and an effective, feasible and safe technique when treating ruptured ACLs in skeletally immature patients.

Outcomes of Quadriceps Tendon With Patellar Bone Block Anterior Cruciate Ligament Reconstruction in Adolescent Patients With a Minimum 2-Year Follow-up

BACKGROUND

The incidence of anterior cruciate ligament (ACL) injury in the adolescent population is increasing. The quadriceps tendon-patellar bone autograft (QPA) has been established as a reliable graft choice for ACL reconstruction in the adult population.

PURPOSE

To investigate graft failure, ability to return to sport, patient-reported functional outcomes, joint laxity, and subsequent injury among adolescent patients >2 years after primary ACL reconstruction with the QPA.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Consecutive patients who underwent QPA ACL reconstruction performed by a single surgeon were identified from an existing database. Information available in the database included demographics, concomitant/subsequent injuries, surgical procedures, graft failure, return to sport, and Lachman examination collected by medical record review. Pediatric International Knee Documentation Committee (Pedi-IKDC) and Lysholm scores were collected by telephone or during a clinic visit >2 years postoperatively.

RESULTS

The final cohort included 81 of 104 consecutive adolescent patients aged 10 to 18 years (mean ± SD, 15.9 ± 1.7 years at the time of surgery) for whom follow-up information was collected at >2 years after surgery. The cumulative incidence of graft failure within the 36-month follow-up period was 1.2% (95% CI, 0.1%-11.4%). The rate of ipsilateral non-ACL injuries was similar (1.2%; 95% CI, 0.2%-7.6%). Contralateral ACL and non-ACL injuries requiring surgical intervention were documented in 9.8% (95% CI, 4.9%-19.5%). The median Pedi-IKDC score was 94 (interquartile range, 89-98). The median Lysholm score was 99.5 (interquartile range, 89.0-100.0). At 36 months after surgery, 87.9% (95% CI, 81.4%-94.9%) of individuals had returned to play.

CONCLUSION

The quadriceps tendon-patellar autograft is a novel graft that demonstrates excellent stability and favorable patient-reported outcomes. Based on these results, the QPA is a reliable choice for primary ACL reconstruction in adolescent patients.