Outcomes and Complications After All-Epiphyseal Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients

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.

Return to Sport After Pediatric Anterior Cruciate Ligament Reconstruction: A Systematic Review of the Criteria

BACKGROUND

Postoperative rehabilitation is an important component of recovery after anterior cruciate ligament (ACL) reconstruction (ACLR), facilitating successful return to sport (RTS) by reducing risk factors for repeat injury.

PURPOSE

This systematic review aimed to determine the best protocol for RTS after ACLR in children.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

PubMed, Embase, PEDro, SPORTDiscus, and Web of Science databases were searched from October 3, 2014, to November 3, 2022. The inclusion criteria were the pediatric population (<18 years old) after ACLR with clear RTS criteria and/or mean/median time to RTS. Multiligament knee injuries were excluded from this study. The methodologic quality of the included articles was assessed using the methodological index for non-randomized studies (MINORS). The highest possible score was 24 points for comparative studies (ie, a study comparing 2 protocols or more). Noncomparative studies or studies with a single protocol could score a maximum of 16 points as assessed by the MINORS score.

RESULTS

The search yielded 1816 titles, and 24 were retained based on the inclusion and exclusion criteria. Every study was published between 2015 and 2022. Among the 24 studies included, 13 were retrospective and 11 were prospective. The mean MINORS score for the noncomparative studies was 13 of 16 (n = 23) and 23 of 24 for the comparative study (n = 1). The studies were categorized into unspecified clearance (n = 10), milestone based (n = 13), and combined time and milestone (n = 1). A total of 1978 patients (57% female) were included in the review. The mean age at ACLR was 14.7 years. The most common endpoint used was graft rupture (0% to 35%). In the unspecified group, the quickest RTS was 5.8 months and the longest was 9.6 months. Statistically significant risk factors for ACL reinjury included younger age and earlier RTS. The latter was a significant contributor to graft failure for combined time-based and milestone-based RTS. In the milestone-based group, the most common criteria were ≥90% limb symmetry measured using hamstring strength, quadriceps strength, and/or hop tests. The mean RTS time was 6.8 to 13.5 months.

CONCLUSION

RTS should be delayed, when possible, especially in the younger population. A combination of quantitative tests and qualitative tests is also recommended. However, optimal RTS criteria have yet to be determined. Future prospective studies should focus on comparing the different times and milestones currently available.

Quadriceps tendon autograft is promising with lower graft rupture rates and better functional Lysholm scores than hamstring tendon autograft in pediatric ACL reconstruction. A systematic review and meta-analysis

Purpose

Graft rupture is the most prevalent complication following pediatric anterior cruciate ligament reconstruction (ACLR). The hamstring tendon (HT) autograft is frequently employed, while the quadriceps tendon (QT) autograft has garnered increased attention recently. This study aims to perform a systematic review to assess the complication rates and functional outcomes associated with these two widely used autografts in skeletally immature patients - comparing HT versus QT autografts.

Research question

Is QT autograft better than HT autograft for ACLR in skeletally immature cohorts?

Methodology

Three electronic databases (PubMed/Medline, Scopus, and Ovid) were comprehensively searched to identify pertinent articles reporting the outcomes of HT and QT autografts in pediatric ACLR with a minimum 2-year follow-up. Data on the outcome parameters, such as graft rupture rates, contralateral ACL injury rates, functional outcomes, and growth disturbances rates, were extracted. Meta-analysis was performed using OpenMeta Analyst software.

Results

Twelve studies were included for meta-analysis (pooled analysis) with 659 patients (QT: 205; HT: 454). The analysis showed that QT autografts had a significantly lesser graft rupture rate than HT autografts (3.5 % [95 % CI 0.2, 6.8] and 12.4 % [95 % CI 6.1, 18.7] respectively, p < 0.001). The graft rupture rates between QT with bone and without bone block showed no statistically significant difference (4.6 % [95 % CI 0.8, 1.0] and 3.5 % [95 % CI 2.0, 8.9] respectively, p = 0.181). The overall contralateral ACL injury rate was 10.2 %, and the subgroup analysis revealed no statistically significant difference between the QT and HT groups (p = 0.7). Regarding functional outcome scores at the final follow-up, the mean Lysholm score demonstrated a significant increase in the QT group compared to the HT group (p < 0.001). There were no significant differences between the two groups concerning growth disturbances at the final follow-up. Return to sports (RTS) varied between 6 and 13.5 months after surgery.

Conclusion

QT autografts demonstrate encouraging outcomes, showcasing lower graft rupture rates, better functional outcomes, and comparable contralateral ACL injury rates and growth disturbances relative to the commonly used HT autograft in skeletally immature patients undergoing ACLR.

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.

Anterior cruciate ligament reconstruction in skeletally immature patients is effective: A systematic review

PURPOSE

The present study evaluated the outcomes of anterior cruciate ligament (ACL) reconstruction in children with open physes. The outcomes of interest were to compare the increase in joint laxity and PROMs from baseline to the last follow-up, the rate and features of the return to sport and the rate of complications.

METHODS

This study was conducted according to the 2020 PRISMA guidelines. In October 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar and Embase. All the clinical studies investigating ACL reconstruction in skeletally immature patients were accessed. Only articles which clearly stated that surgeries were conducted in children with open physis were eligible.

RESULTS

Data from 53 studies (1691 procedures) were collected. 35% (597 out of 1691 patients) were women. The mean length of the follow-up was 44.7 ± 31.3 months. The mean age of the patients was 12.7 ± 1.1 years old. All PROMs significantly improved from the baseline values to those at the last follow-up. The mean time to return to sport was 8.3 ± 1.9 months. 89% (690 out of 771 patients) returned to sports, 15% (109 out of 721 patients) reduced their level of sports activity or league, and 84% (651 out of 771 patients) returned to their previous level of sport. 9% (112 out of 1213) of patients experienced re-tear of the reconstructed ACL, and 11% (75 out of 660) of patients underwent a further ACL reoperation. No patients (0 out of 83) demonstrated increased laxity at the last follow-up, and persistent sensation of instability was reported by 5% (11 out of 235) of patients.

CONCLUSION

ACL reconstruction in skeletally immature patients is effective and safe, and is associated with fast recovery and a high rate of return to sport.

LEVEL OF EVIDENCE

Level IV.

The Risk of Growth Disturbance Is Low After Pediatric Anterior Cruciate Ligament Reconstruction With a Femoral Growth Plate Sparing Technique

Purpose

To evaluate radiological tibial and femoral length and axis growth disturbances, as well as clinical outcome in skeletal immature anterior cruciate ligament reconstruction (ACLR) patients treated with a femoral growth plate-sparing ACLR technique.

Methods

Skeletally immature patients who underwent operation between 2013 to 2019 with ALCR using the femoral growth plate-sparing technique were investigated with follow-up after growth plate closure. The inclusion criteria were isolated ACL rupture in patients with open physis in the distal femur and proximal tibia seen at plain radiography. The minimum follow-up time was 29 months. Patients were evaluated with full extremity radiographs measuring limb length discrepancy and coronal knee alignment compared to contralateral leg, as well as clinical evaluation with Rolimeter measurements and the Knee Osteoarthritis Outcome Score (KOOS), the International Knee Documentation Committee subjective knee form (IKDC), and Tegner Activity Scale scores.

Results

Sixty-five patients were examined with radiography, and 52 patients were assessed with clinical examination. The mean follow-up time was 68 (range, 29-148) months. No limb-length discrepancy (-0.65 mm [confidence interval {CI}, -2.21 to 0.92]) or angular deformity at tibia (-0.25° [CI, -0.78° to 0.28°]) was found. There was a small but statistically significant different angular deformity at the distal femur compared to the contralateral leg (-1.51° [CI, -2.31 to -0.72]) at follow-up. The side-to-side difference in knee laxity at follow-up was 2.4 mm. At follow-up the KOOS Sport, KOOS Quality of Life (QoL), IKDC, and Tegner scores were 80, 75, 86, and 5, respectively. Sixty-seven percent of the patients met the Patient Acceptable Symptom State, and 52% reported results exceeding the KOOS Sport MCID Level and 69% the KOOS QoL level.

Conclusions

Femoral physis-sparing ALCR is associated with a low risk of alignment and length disturbances. The technique provides otherwise good subjective clinical outcome and knee stability.

Level of Evidence

Level IV, therapeutic case series.

Management of anterior cruciate ligament tears in Tanner stage 1 and 2 children: a narrative review and treatment algorithm guided by ACL tear location

The incidence of anterior cruciate ligament (ACL) tears in skeletally immature patients has acutely increased over the last 20 years, yet there is no consensus on a single "best treatment." Selection of an optimal treatment is critical and based on individual circumstances; consequently, we propose a treatment-selection algorithm based on skeletal development, ACL tear location, type, and quality, as well as parental perspective in order to facilitate the decision-making process. We combined our surgical group's extensive case histories of ACL tear management in Tanner Stage 1 and 2 patients with those in the literature to form a consolidated data base. For each case the diagnostic phase, communication with patient and parents, treatment choice(s), selected surgical techniques and rehabilitation schedule were critically analyzed and compared for patient outcomes. MRI-imaging and intraoperative tissue quality assessment were preeminent in importance for selection of the optimal treatment strategy. Considerations for selecting an optimal treatment included: associated lesions, the child/patient and parent(s)' well-informed and counseled consent, biological potential, and the potential for successful ACL preservative surgery. Complete ACL tears were evaluated according to tear-location. In type I and II ACL tears with remaining good tissue quality, we propose primary ACL repair. In type III and IV ACL tears we propose physeal-sparing reconstruction with an iliotibial band graft. Finally, in the case of a type V ACL tear, we propose that the best treatment be based on the Meyers-McKeever classification. We present a facile decision-making algorithm for ACL management in pediatric patients based on specific elements of tissue damage and status.

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.

Intrarater and Interrater Reliability of Radiographic Characteristics in Skeletally Immature Patients With Anterior Cruciate Ligament Tears: A PLUTO Study Group Reliability Study

BACKGROUND

Radiographic measurements of limb alignment in skeletally immature patients with anterior cruciate ligament (ACL) tears are frequently used for surgical decision-making, preoperative planning, and postoperative monitoring of skeletal growth. However, the interrater and intrarater reliability of these radiographic characteristics in this patient population is not well documented.

HYPOTHESIS

Excellent reliability across 4 raters will be demonstrated for all digital measures of length, coronal plane joint orientation angles, mechanical axis, and tibial slope in skeletally immature patients with ACL tears.

STUDY DESIGN

Cohort study (diagnosis).

METHODS

Three fellowship-trained orthopaedic surgeons and 1 medical student performed 2 rounds of radiographic measurements on digital imaging (lateral knee radiographs and long-leg radiographs) of skeletally immature patients with ACL tears. Intrarater and interrater reliability for continuous radiographic measurements was assessed with intraclass correlation coefficients (ICCs) across 4 raters with 95% CIs for affected and unaffected side measurements. Interrater reliability analysis used an ICC (2, 4) structure and intrarater reliability analysis used an ICC (2, 1) structure. A weighted kappa coefficient was calculated for ordinal variables along with 95% CIs for both interrater and intrarater reliability. Agreement statistic interpretations are based on scales described by Fleiss, and Cicchetti and Sparrow: <0.40, poor; 0.40 to 0.59, fair; 0.60 to 0.74, good; and >0.74, excellent.

RESULTS

Radiographs from a convenience sample of 43 patients were included. Intrarater reliability was excellent for nearly all measurements and raters. Interrater reliability was also excellent for nearly all reads for all measurements.

CONCLUSION

Radiographic reliability of long-leg radiographs and lateral knee x-rays in skeletally immature children with ACL tears is excellent across nearly all measures and raters and can be obtained and interpreted as reliable and reproducible means to measure limb length and alignment.

LEVEL OF EVIDENCE

Level III.

Clinical outcomes of different autografts used for all-epiphyseal, partial epiphyseal or transphyseal anterior cruciate ligament reconstruction in skeletally immature patients - a systematic review

BACKGROUND

Different types of grafts can be used for anterior cruciate ligament reconstruction (ACLR). There is little published data regarding skeletally immature patients. The purpose of this systematic review was to assess the clinical outcomes and complications for different autograft types used in all-epiphyseal, transphyseal and partial epiphyseal/hybrid ACLR in skeletally immature children and adolescents.

METHODS

PubMed, Embase and Cochrane databases were systematically searched for literature regarding ACLR using hamstrings, quadriceps or bone-patellar-tendon-bone (BPTB) autografts in skeletally immature patients. Studies were included if they examined at least one of the following outcomes: graft failure, return to sport(s), growth disturbance, arthrofibrosis or patient reported outcomes and had a minimum follow-up of 1 year. Case reports, conference abstracts and studies examining allografts and extra-articular or over-the-top ACL reconstruction techniques were excluded. Graft failure rates were pooled for each graft type using the quality effects model of MetaXL. A qualitative synthesis of secondary outcomes was performed.

RESULTS

The database search identified 242 studies. In total 31 studies were included in this review, comprising of 1358 patients. Most patients (81%) were treated using hamstring autograft. The most common used surgical technique was transphyseal. The weighted, pooled failure rate for each graft type was 12% for hamstring tendon autografts, 8% for quadriceps tendon autografts and 6% for BPTB autografts. Confidence intervals were overlapping. The variability in time to graft failure was high. The qualitative analysis of the secondary outcomes showed similar results with good clinical outcomes and low complication rates across all graft types.

CONCLUSIONS

Based on this review it is not possible to determine a superior graft type for ACLR in skeletally immature. Of the included studies, the most common graft type used was the hamstring tendon. Overall, graft failure rates are low, and most studies show good clinical outcomes with high return to sports rates.

Overgrowth of long bone in rabbits by growth stimulation through metaphyseal hole creation

Overgrowth of long bones was noted in pediatric patients who underwent anterior cruciate ligament reconstruction. Hyperaemia during creating a metaphyseal hole and the microinstability made by the drill hole may induce overgrowth. This study aimed to determine whether metaphyseal hole creation accelerates growth and increases bone length and compare the effects of growth stimulation between metaphyseal hole creation and periosteal resection. We selected 7- to 8-week-old male New Zealand white rabbits. Periosteal resection (N = 7) and metaphyseal hole creation (N = 7) were performed on the tibiae of skeletally immature rabbits. Seven additional sham controls were included as age-matched controls. In the metaphyseal hole group, the hole was made using a Steinman pin at the same level of periosteal resection, and the cancellous bone beneath the physis was removed by curettage. The vacant space in the metaphysis below the physis was filled with bone wax. Tibiae were collected 6 weeks after surgery. The operated tibia was longer in the metaphyseal hole group (10.43 ± 0.29 cm vs. 10.65 ± 0.35 cm, P = 0.002). Overgrowth was higher in the metaphyseal hole group (3.17 ± 1.16 mm) than in the sham group (- 0.17 ± 0.39 mm, P < 0.001). The overgrowth in the metaphyseal hole group was comparable to that in the periosteal resection group (2.23 ± 1.52 mm, P = 0.287). In rabbits, metaphyseal hole creation and interposition with bone wax can stimulate long bone overgrowth, and the amount of overgrowth is similar to that seen in periosteal resection.

Growth Disturbances Following Paediatric Anterior Cruciate Ligament Reconstruction: A Systematic Review

Growth disturbances after transphyseal paediatric anterior cruciate ligament (ACL) reconstruction have led to the development of physeal-sparing techniques. The aim of this study is to investigate growth disturbances following paediatric ACL reconstruction and identify associated risk factors. A systematic search on PubMed, Scopus and Web of Science databases was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify case series reporting paediatric ACL reconstructions. Of 518 articles, 78 met the inclusion criteria, and data related to growth disturbances and graft failures were extracted. A total of 2,693 paediatric ACL reconstructions resulted in 70 growth disturbances (2.6%): 17 were varus, 26 were valgus, 13 were shortening, 14 were lengthening and five patients had reduced tibial slope. Some patients showed deformities in more than one plane. Coronal plane deformities were seen more frequently with eccentric physeal arrest and lengthening with intraepiphyseal tunnelling. Shortening and reduced tibial slope were related to large central physeal arrest and anterior tibial physeal arrest, respectively. Sixty-two studies documented 166 graft failures in 2,120 reconstructions (7.8%). The extraphyseal technique was least likely to result in growth disturbances and graft failure. Paediatric ACL reconstruction is a safe and effective treatment of rupture. Growth disturbances are least likely following extraphyseal tunnelling, and those resulting from transphyseal techniques can be minimised by reducing drill size, drilling steep and avoiding the physeal periphery. The insertion of hardware, synthetic material, or a bone plug through the drilled physis should be avoided. There is a greater need for robust long-term data collection, such as national ligament registries, to standardise practice and evaluate the risk of growth disturbance and re-ruptures in this treatment.

Criteria Used to Determine Unrestricted Return to Activity After ACL Reconstruction in Pediatric and Adolescent Patients: A Systematic Review

Background

The rates of anterior cruciate ligament (ACL) graft failure or contralateral ACL rupture range from 17% to 30% in pediatric patients after ACL reconstruction (ACLR). A contributing factor to the high reinjury rate in this population may be the limited evidence regarding appropriate criteria for allowing unrestricted return to activity (RTA) postoperatively.

Purpose

To review the literature and identify the most commonly used criteria when determining unrestricted RTA after ACLR in pediatric patients.

Study Design

Systematic review; Level of evidence, 4.

Methods

A search was performed of the Medline/PubMed, Cochrane Central Register of Controlled Trials, Embase, CINAHL, and SPORTDiscus databases using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The authors identified studies that included pediatric patients (<19 years of age) and specified the criteria used to determine RTA after ACLR.

Results

A total of 27 articles met all criteria for review, of which 13 studies only used 1 criterion when determining RTA. Objective criteria were the most common type of criteria for RTA (17 studies). Strength tests (15 studies) and hop tests (10 studies) were the most commonly used tasks when deriving RTA criteria. Only 2 studies used validated questionnaires to assess the patient's physiological readiness for RTA, and only 2 studies used an objective assessment of movement quality before RTA.

Conclusion

Only 14 of the 27 reviewed studies reported using >1 criterion when determining RTA. Furthermore, few studies used patient-reported outcome measures or lower limb kinematics as RTA criteria, indicating that more research is needed to validate these metrics in the pediatric population.

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

Background

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

Methods

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

Results and Conclusions

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

Level of evidence

level IV.

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.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Anterior Cruciate Ligament Reconstruction Procedures Using the Iliotibial Band Autograft

The Micheli anterior cruciate ligament (ACL) procedure is a combined intra-articular and extra-articular knee stabilization technique that combines lateral augmentation with ACL reconstruction using the iliotibial band as an autograft for both aspects of the technique. Its primary indication is for ACL reconstruction in skeletally immature patients with more than 2 years of growth remaining. Studies have shown it to be effective at restoring knee biomechanics to have minimal risk of complications, including those associated with growth disturbances and a relatively low ACL graft rupture rate. Additional studies are needed to better understand the potential utilization of this technique and related modifications in the marginally skeletally immature patient, skeletally mature adolescent, adult, and revision ACL reconstruction settings.

Physeal-Sparing Anterior Cruciate Ligament Reconstruction with Iliotibial Band Autograft in the Skeletally Immature Knee

Conventional adult anterior cruciate ligament reconstruction techniques are controversial in skeletally immature patients due to the risk of iatrogenic physeal damage and potential growth disturbance. The physeal-sparing, combined intra- and extra-articular anterior cruciate ligament reconstruction using an autogenous iliotibial band was developed to mitigate this risk in prepubescent, skeletally immature patients, with excellent functional outcomes and a low revision rate. This article describes the surgical details of this reproducible reconstruction technique.

The Spectrum of Anterior Cruciate Ligament Reconstruction Options for the Pediatric and Adolescent Patient: A Narrative Review

As youth sports participation has increased in recent years, injuries to the anterior cruciate ligament (ACL) have become increasingly common in pediatric patients. Historically, ACL reconstruction was delayed in pediatric patients to avoid physeal damage with the potential for leg-length discrepancy or angular deformity. Current research shows that delaying reconstruction or choosing nonoperative management is associated with increased rates of meniscal and chondral injuries, persistent knee instability, and low rates of return to previous activity. Early ACL reconstruction using techniques to avoid physeal growth disturbance is now widely accepted among physicians. The purpose of this review was to describe the pediatric ACL in terms of the relevant anatomy and biomechanics, physical examination, and diagnostic imaging. In addition, the importance of skeletal age and possible physeal injury is discussed in the context of ACL reconstruction options by skeletal age and remaining growth potential.

17-Year Results following Transepiphyseal Anterior Cruciate Ligament Reconstruction in Children and Adolescents

OBJECTIVE

Rupture of the anterior cruciate ligament (ACL) in childhood and adolescence is a serious injury. It is now known that conservative therapy of an unstable knee joint in childhood or adolescence under can lead to poor subjective and objective results. The aim of this study is to record long-term results after transepiphyseal ACL reconstruction using autologous hamstring tendons and extracortical fixation in childhood and adolescence with open physes - at least 15 years after surgery.

METHODS

Our internal registry was used to identify all patients who received surgical treatment of an acl tear during childhood and adolescence by transepiphyseal acl reconstruction more than 15 years previously. In these patients, the International Knee Documentation Committee for Subjective Knee Form (IKDCsubj.), Knee Injury and Osteoarthritis Outcome Score (KOOS), Tegner Activity Score (TAS) and Lysholm Score were collected, and clinical and magnetic resonance imaging (MRI) examinations were performed.

RESULTS

A total of 22 patients were identified, 5 of whom could not be contacted. The mean age at the time of surgery was 13.1 years, and the mean follow-up time was 17.4 years. In 3 patients, a traumatic tear was observed with subsequent reconstruction of the ACL. None of the included patients showed a growth disorder during the course of the study. The IKDC_subj. was 92.4 ± 14.7 (48 - 100), the Lysholm score was 87.9 ± 16.9 (34 - 100), the TAS was 5.7 ± 2.3 (3 - 9) and the pain level based on VAS was 3.5 ± 2.6 (1 - 8) points. The values showed subjective and objective deterioration compared to the 10-year results, with no statistical significance. The following subscores were reported for the KOOS: KOOS_pain 90.9 ± 17.6 (28 - 100); KOOS_symptom 82.9 ± 22.6 (11 - 100); KOOOS_ADL 94.3 ± 13.7 (44 - 100); KOOS_Sport 80.3 ± 26.4 (15 - 100); KOOS_QOL 80.9 ± 25.8 (0 - 100). 13 of the 17 patients could also be clinically and radiologically examined. In 92% of patients, an intact acl reconstruction was found without evidence of cartilage or meniscus damage. The mean lateral difference in the KT-1000 measurement was 1.5 mm.

CONCLUSION

ACL reconstruction in childhood and adolescence provides good functionality and stability of the knee joint over the long term. Secondary signs of osteoarthritis can only be detected in isolated cases by MRI. ACL reconstruction using the transepiphyseal technique can be considered the method of choice for open growth plate knee joints.

Outcomes Following Primary Anterior Cruciate Ligament Reconstruction Using a Partial Transphyseal (Over-the-Top) Technique in Skeletally Immature Patients

BACKGROUND

The incidence of anterior cruciate ligament (ACL) injuries in skeletally immature patients is increasing, with ACL reconstruction preferred in this population due to reported chondroprotective benefits. Due to concerns with growth disturbance following ACL reconstruction in skeletally immature patients, various physealsparing and partial transphyseal techniques have been developed. Currently, there is no consensus on the most effective ACL reconstruction technique in skeletally immature patients. The purpose of the current study was to report the outcomes of a partial-transphyseal over-the-top (OTT) ACL reconstruction in a cohort of skeletally immature patients.

METHODS

All patients with radiographic evidence of open tibial and femoral physes that underwent primary ACL reconstruction using a partial-transphyseal OTT technique between 2009-2018 at a single tertiary-care institution with at least twelve months of clinical follow-up were retrospectively reviewed. Patient demographics, physical examination findings, graft ruptures, return to sport, and Tegner activity levels were analyzed. Statistical significance was defined as p<0.05.

RESULTS

Overall, 11 males and 1 female (12 knees) with a mean age of 12.8±1.8 (range: 10-16) years were included in the study. The mean postoperative follow-up of the cohort was 2.3±1.2 (range: 1.1-5.2) years. All ACLs were reconstructed with hamstring autograft with allograft augmentation utilized in a single patient. There were two cases of ACL graft rupture (16.7%). All patients were able to return to the same or higher level of sporting activity at an average of 7.4+2.7 months. There were no cases of clinically significant longitudinal or angular growth disturbance.

CONCLUSION

Partial transphyseal ACL reconstruction using a transphyseal tibial tunnel and an extra-articular OTT technique on the femur in skeletally immature patients affords minimal risk of growth disturbance with a graft rupture rate consistent with what has been reported in this high-risk population. All patients were able to return to sport at the same or higher level. Level of Evidence: IV.

Improved epiphyseal socket placement with intraoperative 3D fluoroscopy: a consecutive series of pediatric all-epiphyseal anterior cruciate ligament reconstruction

PURPOSE

Disturbance of the growth plate during all-epiphyseal anterior cruciate ligament reconstruction (ACLR) socket placement is possible due to the undulation of the distal femoral physis and proximal tibial physis. Therefore, it is important to obtain intraoperative imaging of the guide wire prior to reaming the socket. The purpose of this study was to investigate the effect of the use of 3D intraoperative fluoroscopy on socket placement in patients undergoing all-epiphyseal ACLR. It was hypothesized that 3D imaging would allow for more accurate intraoperative visualization of the growth plate and hence a lower incidence of growth plate violation compared to 2D imaging.

METHODS

Patients under the age of 18 who underwent a primary all-epiphyseal ACL reconstruction by the senior authors and had an available postoperative MRI were retrospectively reviewed. Demographic data, surgical details, and the distances between the femoral socket and distal femoral physis (DFP) and tibial socket and proximal tibial physis (PTP) were recorded. Patients were split into two groups based on type of intraoperative fluoroscopy used: a 2D group and a 3D group. Interrater reliability of radiographic measurements was evaluated using intraclass correlation coefficient (ICC).

RESULTS

Seventy-two patients fit the inclusion criteria and were retrospectively reviewed. 54 patients had 2D imaging and 18 patients had 3D imaging. The mean age at time of surgery was 12.3 ± 1.5 years, 79% of patients were male, and 54% tore their left ACL. The mean time from surgery to postoperative MRI was 2.0 ± 1.1 years. The ICC was 0.92 (95% CI 0.35-0.98), indicating almost perfect interrater reliability. The mean difference in distance between the tibial socket and the PTP was significantly less in the 2D imaging group than the 3D imaging group (1.2 ± 1.7 mm vs 2.5 ± 2.2 mm, p = 0.03). The femoral and tibial sockets touched or extended beyond the DFP or PTP, respectively, significantly less in the 3D group than in the 2D group (11% vs 43%, p < 0.000, 17% vs 65%, p < 0.000).

CONCLUSION

There was a significantly increased distance from the PTP and decreased incidence of DFP violation with use of 3D intraoperative imaging for all-epiphyseal ACLR socket placement. Surgeons should consider utilizing 3D imaging prior to creating femoral and tibial sockets to potentially decrease the risk of physis violation in these patients.

LEVEL OF EVIDENCE

III.

Assessment of Skeletal Maturity and Postoperative Growth Disturbance After Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients: A Systematic Review

BACKGROUND

Growth disturbance is an uncommon but potentially serious complication after anterior cruciate ligament (ACL) reconstruction in skeletally immature patients.

PURPOSE

To describe how the pediatric ACL literature has assessed preoperative skeletal maturity and the amount of growth remaining and to comprehensively review the incidence, reporting, and monitoring of postoperative growth disturbance.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

This review included studies reporting original research of clinical outcomes of skeletally immature patients after ACL reconstruction. Patient characteristics, surgical techniques, preoperative assessments of skeletal maturity or growth remaining, and postoperative assessments of growth disturbances were extracted.

RESULTS

A total of 100 studies met inclusion criteria. All studies reported chronological age, and 28 studies (28%) assessed skeletal age. A total of 44 studies (44%) used Tanner staging, and 12 studies (12%) obtained standing hip-to-ankle radiographs preoperatively. In total, 42 patients (2.1%) demonstrated a leg length discrepancy (LLD) >10 mm postoperatively, including 9 patients (0.5%) with LLD >20 mm; furthermore, 11 patients (0.6%) with LLD underwent growth modulation. Shortening was the most common deformity overall, but overgrowth was reported more frequently in patients who had undergone all-epiphyseal techniques. Most LLDs involved the femur (83%). A total of 26 patients (1.3%) demonstrated a postoperative angular deformity ≥5°, and 9 of these patients underwent growth modulation. The most common deformities were femoral valgus (41%), tibial recurvatum (33%), and tibial varus (22%). Although standing hip-to-ankle radiographs were the most common radiographic assessment of growth disturbance, most studies inadequately reported the clinical and radiographic methods of assessment for growth disturbance. Additionally, only 35% of studies explicitly followed patients to skeletal maturity.

CONCLUSION

This systematic review described significant variability in the reporting and monitoring of growth-related complications after ACL reconstruction in skeletally immature patients. The incidence of LLD and angular deformity appeared to be low, but the quality of research was not comprehensive enough for accurate assessment.

REGISTRATION

CRD42019136059 (PROSPERO).

Graft Choice for Anterior Cruciate Ligament Reconstruction in Women Aged 25 Years and Younger: A Systematic Review

CONTEXT

Although anterior cruciate ligament (ACL) tears are relatively common in athletic populations, few studies have systematically reviewed graft choice in young women.

OBJECTIVE

To quantitatively and qualitatively examine reported outcomes for graft choice in women aged 25 years and younger undergoing primary ACL reconstruction.

DATA SOURCE

A systematic review was performed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. An electronic search in the PubMed (includes MEDLINE) and EMBASE databases was completed using a combination of key terms.

STUDY SELECTION

Studies were included if they reported graft choice outcomes in women aged 25 years and younger.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

The following information was extracted: title, author, year of publication, number of female patients and age, graft type, follow-up, and patient-reported outcome measures. The following outcome scores were identified as being reported or not reported by each study: graft failure, contralateral ACL (CACL) rupture, IKDC (International Knee Documentation Committee), graft survival (Kaplan-Meier), Lysholm, Tegner, KT-1000, kneeling pain, return to sport, and Lachman.

RESULTS

Of 1170 identified articles, 16 met inclusion criteria, reporting on 1385 female patients aged 25 years and younger. Comparison of 655 bone-patellar tendon-bone (BPTB) versus 525 hamstring tendon (HT) autografts showed significant differences in mean failure rate between BPTB autografts (6.13% ± 2.58%) and HT autografts (17.35% ± 8.19%), P = 0.001. No statistically significant differences in CACL failure rates were found between BPTB autografts and HT autografts (P = 0.25). Pooled results for IKDC were possible in 3 of the HT autograft studies, showing a mean score of 88.31 (95% CI 83.53-93.08). Pooled Lysholm score results were possible in 2 of the HT autograft studies, showing a mean score of 93.46 (95% CI 91.90-95.01).

CONCLUSION

In female patients aged 25 years and younger, BPTB autografts showed significantly less graft failure compared with HT autografts. However, BPTB autografts had comparable patient-reported outcomes compared with HT autografts with the available data. The overall state of evidence for graft choice in female patients aged 25 years and younger is low. Future studies should report statistics by age and sex to allow for further analysis of graft choice for this specific population that is known to be more vulnerable to ACL injury.

Complication rates following all-epiphyseal ACL reconstructions in skeletally immature patients: A retrospective case series study

The aim was to evaluate the safety of a physeal-sparing anterior cruciate ligament reconstruction technique (ACLR), performed with Orthopediatrics (Warsaw, IN) equipment, by assessing complications.Skeletally immature patients who underwent all-epiphyseal ACLR between 2015 and 2017 with postoperative follow-up were included in this retrospective study. Complications, demographic, clinical, surgical, and imaging data was retrieved from an urban tertiary pediatric hospital database. Physeal status, limb-length discrepancies (LLD), and angular deformities were assessed on preoperative and postoperative radiographs, growth disturbances were reported, and initial and follow-up diameters of tunnels were compared.Nineteen ACLRs were included from 18 patients, 4 females and 14 males, with bone age at surgery of 13.3 ± 1.0 years. At a mean follow-up of 19.2 ± 10.1 months, there were no symptomatic growth disorders requiring intervention. There were: 2 (11.1%) unilateral early physeal closures, 2 (10.5%) new angular deformities (5°-10°), 4 (22.2%) LLD (1-2 cm), 1 (5.6%) contralateral ACLR, 1 (5.6%) femoral screw removal, 2 (10.5%) graft ruptures, and 1 meniscal tear (5.3%). Mean tunnel widening was 1.7 mm and 1.5 mm on the femoral and tibial side, respectively, and no massive osteolysis was recorded at the polyetheretherketone implant site.The complication rates were comparable to those in similar studies, with no growth-related complications at 19.2 months.

Age, rehabilitation and surgery characteristics are re-injury risk factors for adolescents following anterior cruciate ligament reconstruction

OBJECTIVES

To examine the effect of age on post-ACLR rehabilitative outcomes and identify surgical/rehabilitative characteristics as ACL re-injury risk factors in adolescents.

DESIGN

Cohort study.

SETTING

Children's hospital.

PARTICIPANTS

273 adolescents with first-time ACLR.

MAIN OUTCOME MEASURES

Demographics, injury history, surgery, and outcomes documented during post-ACLR physical therapy (PT) sessions were extracted from medical records. Effects of age on outcomes were examined using multivariate regression. ACL re-injury risk factors were identified using survival analysis with Cox regression.

RESULTS

Re-injury was recorded in 47 patients (17.2%) with a median follow-up time of 3.1 years and median re-injury time of 13.4 months post-surgery. Younger age (Hazard-Ratio, HR = 1.264 per year decrease; P = 0.005), receiving surgery within 1 month post-injury (HR = 3.378 vs. >3 months; P = 0.012), starting PT within 3 days post-surgery (HR = 3.068; P = 0.022), and decreased number of PT sessions (HR = 1.118 per 3-session decrease; P = 0.010) increased re-injury risk. Although age was associated with re-injury risk, age was not associated with any outcome (P > 0.059).

CONCLUSION

Adolescents who are younger, receive surgery and post-surgery PT sooner, or attend fewer PT sessions may be at an increased re-injury risk. Younger patients achieved similar outcomes despite elevated re-injury risk. Current discharge criteria are inadequate in identifying high re-injury risk patients.

Physeal-sparing posteromedial portal approach reduced distance between guide pin and neurovascular structures

PURPOSE

To compare a femoral physeal sparing anterior cruciate ligament (ACL) reconstruction technique utilizing a posteromedial portal to traditional transphyseal techniques with regards to anatomic tunnel positioning and proximity to important neurovascular structures.

METHODS

Eight cadaveric knees were obtained for the study. Femoral tunnel guide pins were placed utilizing four different techniques: accessory anterior medial portal, posteromedial portal, trans-tibial, and figure-4 methods. The knees were then dissected and the following measurements taken: distance of each pin to the saphenous and peroneal nerve, popliteus tendon, neurovascular bundle, femoral ACL footprint and articular cartilage, and the angle of the guide pin entering the lateral femoral condyle. Fluoroscopic imaging was taken to determine the disruption of the physeal scar.

RESULTS

Posteromedial portal guide pin was significantly closer to the neurovascular bundle, popliteal tendon and saphenous nerve when compared to the other 3 techniques, but was further from the peroneal nerve. It also had the smallest distance from the anatomic footprint of the ACL, and the largest angle to the lateral femoral condyle. The posteromedial portal guide pin had similar distance from the articular cartilage as the accessory anterior medial portal and figure-4 guide pin, with the trans-tibial guide pin being the farthest. The posteromedial portal guide pin failed to disrupt the physeal scar in all specimens, while the other three techniques consistently violated the physeal scar.

CONCLUSION

The posteromedial portal technique offers an appropriate method for anatomic ACL reconstruction while protecting the distal femoral physis from injury. Care needs to be taken with this technique as it comes in closer proximity to some of the important neurovascular structures. This study indicates that posteromedial portal technique is a less technically challenging approach for physeal-sparing ACL repair with special attention required for the protection of neurovascular bundle from potential injury.

Eponyms in Pediatric Sports Medicine: A Historical Review

The use of eponyms in the orthopedics literature has come under scrutiny, and there is a growing body of literature evaluating the utility of these terms in modern healthcare delivery. Although the field of pediatric orthopedic sports medicine is a relatively modern subspecialty, it is built on a foundation of over 100 years of pediatric musculoskeletal medicine. As a result, eponyms account for a significant portion of the vernacular used in the field. The purpose of this review is to summarize and describe the history of common eponyms relevant to pediatric sports pathology, examination maneuvers, classification systems, and surgical procedures. Use of eponyms in medicine is flawed. However, an improved understanding of these terms allows for informed use in future scientific discourse, patient care and medical education and may encourage future innovation and research into understanding pediatric orthopedic pathologies.

Anterior Cruciate Ligament Injuries in Skeletally Immature Patients: A Meta-analysis Comparing Repair Versus Reconstruction Techniques

BACKGROUND

Anterior cruciate ligament (ACL) surgery remains challenging in the skeletally immature patient. Despite the widespread use of physeal-sparing reconstruction techniques, there has been renewed interest in the ACL repair. The purpose of this study was to systematically review the literature to better understand outcomes following all-epiphyseal (AE) reconstruction to extraphyseal reconstruction, while also evaluating ACL repair outcomes in skeletally immature patients.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, all studies in the literature from January 1970 to August 2019 reporting on skeletally immature patients undergoing ACL surgery were identified. Inclusion criteria were pediatric patients with open physes indicative of skeletal immaturity sustaining complete ACL ruptures treated with AE reconstruction, extraphyseal reconstruction or ACL repair. Chronologic age, bone age, postoperative outcomes scores, return to sport rate, and the incidence of complications, namely reruptures, were analyzed.

RESULTS

A total of 14 studies comprising 443 patients were identified. No significant difference in chronologic age or postoperative outcome scores at final follow-up were appreciated between patients undergoing AE versus extraphyseal reconstruction. Return to activity rate was significant greater following extraphyseal reconstruction when compared with AE reconstruction. The incidence of any limb-length discrepancies and limb discrepancies measuring ≥10 mm were significant higher following AE reconstruction, while rerupture rates were more common following AE reconstruction.

CONCLUSIONS

Patients undergoing AE reconstruction possessed significantly lower return to activity rates, higher incidences of limb-length discrepancies and more commonly experienced ACL reruptures when compared with patients undergoing extraphyseal reconstruction. Further investigations analyzing results following ACL repair in skeletally immature patients are warranted to allow for the comparison of outcomes with current physeal-sparing reconstruction techniques.

LEVEL OF EVIDENCE

Level IV-systematic review-therapeutic study.

Which Metrics Are Being Used to Evaluate Children and Adolescents After ACL Reconstruction? A Systematic Review

Purpose

To identify a comprehensive list of outcome measures previously used in the literature to evaluate clinical outcomes after reconstruction of the anterior cruciate ligament (ACL) in patients 18 years of age or younger.

Methods

A literature search was performed by querying MEDLINE, Embase and Cochrane computerized databases for relevant articles that reported clinical outcomes in pediatric patients undergoing ACL reconstruction. Studies that were nonclinical, that reported on patients older than 19 years, that were not available in English, or that included fewer than 10 patients were excluded. Outcome measures of all eligible studies were recorded.

Results

We identified 77 studies published between 1986 and 2018 in 20 peer-reviewed journals. The mean age of the patients was 13.9 years. The ACL rerupture rate was reported in 60% of studies; 32 studies (42%) reported a rate of return to preinjury activity or sports. The use of adult-validated patient-reported outcome measures were reported in 63 (82%) articles. The Lysholm (64%), International Knee Documentation Committee (IKDC) (56%) and Tegner (37%) scores were the most commonly reported. Two patient-reported outcome measures designed for pediatric patients (the Pedi-IKDC and Hospital for Special Surgery Pediatric Functional Activity Brief Scale (Pedi-FABS) were employed in 5 (6%) recent studies.

Conclusions

There is variability across studies in the metrics used to assess clinical outcomes following ACL reconstruction in children and adolescents. Validated pediatric-specific instruments were used infrequently.

Clinical Relevance

A large body of existing pediatric ACL-reconstruction literature relies on a variable set of outcome measures that have not been developed or validated for children and adolescents. More recently, contemporary studies have begun to employ pediatric- and adolescent-specific validated measures, yet their use remains uncommon.

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).

Evidence too weak to guide surgical treatment decisions for anterior cruciate ligament injury: a systematic review of the risk of new meniscal tears after anterior cruciate ligament injury

OBJECTIVE

To investigate the risk of new meniscal tears after treatment for anterior cruciate ligament (ACL) injury, in children and adults with and without ACL reconstruction.

DESIGN

Prognosis systematic review (PROSPERO registration number CRD42016036788).

METHODS

We searched Embase, Ovid Medline, Cochrane, CINAHL, SPORTDiscus, PEDro and Google Scholar from inception to 3rd May 2018. Eligible articles included patients with ACL injury (diagnosis confirmed by MRI and/or diagnostic arthroscopy), reported the number of meniscal tears at the time of ACL injury diagnosis/start of treatment and reported the number of new meniscal tears that subsequently occurred. Articles with fewer than 20 patients at follow-up, and articles limited to ACL revision surgery or multi-ligament knee injuries were excluded. Two independent reviewers screened articles, assessed eligibility, assessed risk of bias and extracted data. We judged the certainty of evidence using the Grading of Recommendations Assessment Development and Evaluation (GRADE) working group methodology.

RESULTS

Of 75 studies included in the systematic review, 54 studies with 9624 patients and 501 new meniscal tears were appropriate for quantitative analysis. Heterogeneity precluded data pooling. The risk of new meniscal tears was 0%-21% when follow-up was <2 years, 0%-29% when follow-up was 2 to 5 years, 5%-52% when follow-up was 5 to 10 years and 4%-31% when follow-up was longer than 10 years. The proportion of studies with high risk of selection, misclassification and detection bias was 84%, 69% and 68%, respectively. Certainty of evidence was very low.

CONCLUSION

New meniscal tears occurred in 0%-52% of patients between 4 months and 20 years (mean 4.9±4.4 years) following treatment for ACL injury. The certainty of evidence was too low to guide surgical treatment decisions. This review cannot conclude that the incidence of new meniscal tears is lower if ACL injury is treated with surgery compared with treatment with rehabilitation only.

Pediatric Anterior Cruciate Ligament Reconstruction

The increasing incidence of anterior cruciate ligament injuries in skeletally immature children demands careful attention by orthopedic surgeons. Assessing skeletal age is essential to selecting the appropriate reconstruction technique. Males with a bone age of 15 years or older and females of 13 years and older are ideal candidates for a transphyseal anterior cruciate ligament reconstruction because there is minimal risk of growth disturbance. Children with substantial growth remaining (skeletal age males ≤12 years and females ≤10 years) seem to be at risk for more significant growth disturbance, so we generally recommend physeal-sparing techniques for these younger patients.

Combined Transphyseal and Lateral Extra-articular Pediatric Anterior Cruciate Ligament Reconstruction: A Novel Technique to Reduce ACL Reinjury While Allowing for Growth

BACKGROUND

Treatment of anterior cruciate ligament (ACL) injuries in the adolescent population continues to be complicated by an unacceptably high rate of secondary ACL injury.

PURPOSE

To describe the failure rate and outcomes after a hybrid pediatric ACL reconstruction (ACLR) employing transphyseal hamstring (TPH) autograft combined with an extra-articular technique using an iliotibial band (ITB) autograft.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Consecutive patients undergoing combined TPH-ITB ACLR between January 2012 and April 2017 with a minimum 2-year follow-up were reviewed. With the goal of decreasing ACL graft injury in this high-risk group, this technique employed anteromedial portal drilling for TPH with an extraosseous femoral ITB technique and intra-articular TPH-ITB grafts fixed within the tibial bone tunnel. Demographics, bone age, standing alignment radiograph for growth and mechanical axis grade, return to sport, graft failure, and patient-reported outcome measures were analyzed.

RESULTS

A total of 61 knees in 60 adolescents underwent the combined TPH-ITB ACLR, with 57 knees (93.4%) meeting inclusion criteria with a mean follow-up of 38.5 months (range, 24-78 months). Only 3 of 57 knees (5.3%) sustained ACL reinjury. The mean age was 13.0 years (range, 11-16 years) with 36 male patients (mean bone age, 14.2 years) and 21 female patients (mean bone age, 13.3 years), and 91% of patients (52 of 57) returned to sport. Participants demonstrated a high functional level at final follow-up, with a mean score of 91.2 (range, 46.7-100) on the Pediatric International Knee Documentation Committee (Pedi-IKDC) Subjective Knee Evaluation Form and mean score of 22.4 (range, 4-30) on the Pediatric Functional Activity Brief Scale (Pedi-FABS). To critically assess growth, a cohort with ≥18 months of growth remaining at surgery was evaluated at maturity. No difference was seen in mean operative and nonoperative leg growth (49.7 mm and 49.8 mm). Although no family reported cosmetic or functional alignment or length concerns, 1 of 18 (5.5%) had a final limb length discrepancy >10 mm (12 mm) and a perioperative alignment difference (0-Grade II valgus).

CONCLUSION

Combined TPH-ITB ACLR in adolescents resulted in high activity levels (Pedi-FABS, 22.4; median, 25) and a low (5.3%) graft failure rate at a mean 38.5 months.

All-epiphyseal Anterior Cruciate Ligament Reconstruction Does Not Increase the Risk of Complications Compared With Pediatric Transphyseal Reconstruction

INTRODUCTION

Complication rates after physeal-sparing anterior cruciate ligament reconstruction (ACLR) are known to be high in the paediatric population compared with the adult population. However, the outcomes of these skeletally immature patients after all-epiphyseal reconstruction have not been compared with those after transphyseal reconstructions in a more similar age group. This study compares clinical outcomes and complications between all-epiphyseal and pediatric transphyseal ACLR.

METHODS

We retrospectively reviewed 1,056 pediatric patients undergoing primary ACLR between 2000 and 2015. Of these, 51 were excluded (5 extra-articular and 46 partial transphyseal reconstructions). Demographic data, intraoperative findings and techniques, postoperative complications (including graft rupture, contralateral anterior cruciate ligament [ACL] tear, and meniscus injuries), clearance for sports, range of motion (ROM), and isokinetic strength testing were recorded. Univariate analysis was followed by stepwise, binary logistic regressions to control for confounding factors.

RESULTS

During the study period, 162 patients underwent all-epiphyseal reconstruction (mean age, 12.1 ± 1.8 years) and 843 underwent transphyseal ACLR (mean age, 15.8 ± 1.9 years). At the time of surgery, more meniscus tears were found in the transphyseal group (76% versus 60%; P < 0.01). These patients also had more irreparable meniscus tears requiring partial meniscectomy (35% versus 18%; P < 0.01). Overall, the rates of graft failure, contralateral ACL injury, and new meniscus tears were 10.3%, 6.1%, and 14.2%, respectively. After controlling for confounders in a multivariate model, no difference was found in these postoperative complications between all-epiphyseal and transphyseal ACLR. Furthermore, no clinically significant difference was observed in postoperative ROM or isokinetic strength testing.

DISCUSSION

Skeletally immature patients undergoing all-epiphyseal ACLR had less irreparable meniscus tears than older children undergoing transphyseal reconstruction. After adjusting for age and other confounders, there was no difference in postoperative ROM or strength, nor an increased risk of graft rupture, contralateral ACL injury, or new meniscus tear in these young patients compared with older adolescents undergoing transphyseal ACLR.

LEVEL OF EVIDENCE

Level III.

Outcome Measures After ACL Injury in Pediatric Patients: A Scoping Review

Background

The incidence of anterior cruciate ligament (ACL) injuries in children is increasing. However, no standardized core set of outcome measures exists for evaluating pediatric ACL injuries.

Purpose

To perform a scoping review of the literature to identify patient-reported outcome measures (PROMs) and objective outcome measures used to evaluate pediatric patients after ACL injury and to classify these in accordance with the International Classification of Functioning, Disability, and Health (ICF) domains.

Study Design

Systematic review; Level of evidence, 4.

Methods

The literature was systematically searched with the PubMed, EMBASE, CINAHL, and PEDro databases. The inclusion criteria were Danish, Norwegian, Swedish, German, or English language; publication between 2010 and 2018; pediatric ACL injury (patients ≤15 years old); and outcome measures. The selected papers were screened for title, abstract, and full text in accordance with predefined inclusion and exclusion criteria.

Results

A total of 68 papers (4286 patients; mean ± SD age, 12.2 ± 2.3 years) were included. Nineteen PROMs and 11 objective outcome measures were identified. The most frequently reported PROMs were the International Knee Documentation Committee (IKDC) Subjective Knee Form (51% of studies), Lysholm scoring scale (46% of studies) and Tegner activity rating scale (37% of studies). Additionally, return to sport was reported in 41% of studies. The most frequent objective measures were knee laxity (76% of studies), growth disturbances (69% of studies), range of motion (41% of studies), and muscle strength (21% of studies). With respect to the ICF domains, the IKDC covered all 3 ICF health domains, the Lysholm score covered the Body Structure and Function and the Activity Limitation domains, while the Tegner score covered the Participation Restriction domain. Objectively measured knee joint laxity, range of motion, and muscle strength covered 1 domain (Body Structure and Function).

Conclusion

Pediatric patients with ACL injury were mainly evaluated subjectively with the IKDC and objectively by knee joint laxity. No consensus exists in the evaluation of children after ACL injury. The majority of applied outcome measures are developed for adults. To cover the ICF health domains, future research needs to consider reliable and valid outcome measures relevant for pediatric patients with ACL injury.

Knee Pathology in Young Adults After Pediatric Anterior Cruciate Ligament Injury: A Prospective Case Series of 47 Patients With a Mean 9.5-Year Follow-up

BACKGROUND

The rate of secondary knee injuries after pediatric anterior cruciate ligament (ACL) injury is uncertain, and previous studies are limited because of poor methodology.

PURPOSE

To evaluate the incidence of new meniscal injuries since the initial diagnostic magnetic resonance imaging (MRI) of young adults who sustained a pediatric ACL injury. In addition, to evaluate meniscal and cartilage injuries in the index knee and contralateral knee injuries on MRI at final follow-up (9.5 years). Furthermore, to assess leg length and alignment based on long-leg radiographs.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Study population at final follow-up included 47 young adults who sustained a pediatric ACL injury before age 13 years. They were followed prospectively since the time of injury for a mean 9.5 years at final follow-up. Imaging included diagnostic MRI of the index knee and 3.0-T MRI of both knees at 1-, 2-, and 9.5-year follow-up, in addition to long-leg radiographs at final follow-up. Forty-three patients underwent active rehabilitation without ACL reconstruction initially; 4 were treated with initial ACL reconstruction. At final follow-up, 27 (57%) had undergone ACL reconstruction.

RESULTS

Fourteen patients had meniscal tears in the index knee at final follow-up (prevalence, 30%). The majority of these were in the same location as previously repaired tears (n = 9). Between diagnostic MRI and final follow-up, 16 patients had sustained new meniscal tears to a healthy meniscus (incidence, 34%). At final follow-up, meniscal injuries recorded at baseline or during follow-up were no longer visible and appeared healed in 17 patients (20 tears). MRI at final follow-up showed cartilage injuries in the index knee of 13 patients (28%) and contralateral injuries in 8 patients (meniscus, n = 2; cartilage, n = 5; subchondral fracture, n = 1). Two patients had a leg-length difference >15 mm, and 3 had side-to-side difference in knee alignment >5°.

CONCLUSION

The incidence of new meniscal tears after pediatric ACL injury was 34% during a mean follow-up period of 9.5 years. At final follow-up, 27 patients (57%) had normal menisci, and none had developed knee osteoarthritis. Primary active rehabilitation, close follow-up, and delayed surgery if needed may be a viable and safe treatment option for some pediatric ACL injuries.

Partial Transphyseal Anterior Cruciate Ligament Reconstruction: Clinical, Functional, and Radiographic Outcomes

BACKGROUND

With a steadily increasing rate of anterior cruciate ligament (ACL) injury and reconstruction in the pediatric population, disagreement remains regarding the optimal reconstruction technique for patients with ACL injury and ≥2 years of growth remaining.

PURPOSE

This study aims to quantify the incidence of linear and angular growth disturbance of adolescents undergoing partial transphyseal ACL reconstruction (ACLR) while assessing graft failure rates, reoperation rates, and functional outcomes in the population.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Consecutive patients undergoing partial transphyseal ACLR by 2 surgeons were retrospectively reviewed. Radiographic outcomes, including bilateral limb length, mechanical axis deviation (MAD), mechanical lateral distal femoral angle (MLDFA), and medial proximal tibial angle (MPTA), were measured on long standing anterior-posterior view radiographs postoperatively. Growth disturbance was defined as ≥1-cm leg length discrepancy, ≥1-cm difference in MAD, or 5° difference in MLDFA or MPTA as compared with the nonoperative side and as MAD, MLDFA, or MPTA outside the established range of reference values. Clinical outcomes, including graft failure and reoperation, were recorded at each follow-up visit. Pediatric International Knee Documentation Committee (Pedi-IKDC) scores were collected electronically after last follow-up.

RESULTS

Twenty-four patients (mean ± SD age, 12.3 ± 0.9 years; 79.2% male) with a mean follow-up of 31.5 ± 17.1 months met inclusion criteria for the study. Overall postoperative growth disturbance incidence was 16.7% (4 of 24), but the incidence of growth disturbance was 66.7% (2 of 3) for those patients with >5 years of growth remaining. Seven patients (29.2%) required reoperation, most frequently for hardware removal. Two patients (8.3%) had graft failure with subsequent revision ACL reconstruction. One patient underwent bilateral medial distal femur hemiepiphysiodesis for genu valgum that was present before ACLR, but no other patients required guided growth procedures. In the subset of patients who completed a Pedi-IKDC questionnaire, the mean score was 94.8 ± 5.3.

CONCLUSION

Overall, partial transphyseal ACLR has good functional outcomes and graft failure and reoperation rates, comparable with those seen with transphyseal and all-epiphyseal techniques. While postoperative growth disturbance occurred in 16.7% of the cohort, the severity was mild and well tolerated without necessitating secondary procedures. There is a high rate of growth disturbance of patients with >5 years of growth remaining (66.7%). Partial transphyseal ACLR represents a valid recommendation for adolescent patients with ACL injury and ≤5 years of growth remaining.

Bridge-Enhanced Anterior Cruciate Ligament Repair: Two-Year Results of a First-in-Human Study

Background

Bridge-enhanced anterior cruciate ligament repair (BEAR) combines suture repair of the anterior cruciate ligament (ACL) with a specific extracellular matrix scaffold (the BEAR scaffold) that is placed in the gap between the torn ends of the ACL to facilitate ligament healing.

Purpose/Hypothesis

The purpose of this study was to report the 12- and 24-month outcomes of patients who underwent the BEAR procedure compared with a nonrandomized concurrent control group who underwent ACL reconstruction (ACLR) with an autograft. We hypothesized that the BEAR group would have physical examination findings, patient-reported outcomes, and adverse events that were similar to those of the ACLR group.

Study Design

Cohort study; Level of evidence, 2.

Methods

Ten patients underwent BEAR, and 10 underwent ACLR with a 4-stranded hamstring autograft. At 24 months, 9 of the 10 BEAR patients and 7 of the 10 ACLR patients completed a study visit. Outcomes reported included International Knee Documentation Committee (IKDC) subjective and objective results, knee anteroposterior (AP) laxity findings via an arthrometer, and functional outcomes.

Results

There were no graft or repair failures in the first 24 months after surgery. The IKDC subjective scores in both groups improved significantly from baseline (P < .0001) at 12 and 24 months, to 84.6 ± 17.2 in the ACLR group and to 91.7 ± 11.7 in the BEAR group. An IKDC objective grade of A (normal) was found in 44% of patients in the BEAR group and in 29% of patients in the ACLR group at 24 months; no patients in either group had C (abnormal) or D (severely abnormal) grades. Arthrometer testing demonstrated mean side-to-side differences in AP laxity that were similar in the 2 groups at 24 months (BEAR, 1.94 ± 2.08 mm; ACLR, 3.14 ± 2.66 mm). Functional hop testing results were similar in the 2 groups at 12 and 24 months after surgery. Hamstring strength indices were significantly higher in the BEAR group compared with the ACLR group (P = .0001).

Conclusion

In this small, first-in-human study, BEAR produced similar outcomes to ACLR with a hamstring autograft. BEAR may result in knee stability and patient-reported outcomes at 2 years sufficient to warrant longer term studies of efficacy in larger groups of patients.

[Anterior cruciate ligament rupture in children with open growth plate : Diagnostics and treatment]

Anterior cruciate ligament (ACL) ruptures in pediatric patients with open growth plate are of concern and the number of injuries is increasing. The possibilities for diagnostics using magnetic resonance imaging (MRI) have improved and are without radiation exposure to the growing skeleton. The MRI should be performed routinely in every case of adequate trauma also to recognize additional injuries to the knee joint. Joint effusion represents an urgent indication for further clarification. Real ACL ruptures have to be distinguished from bony avulsion injuries. Although there are different forms of treatment, biomechanically an ACL insufficiency is present. A permanent instability leads to degenerative changes of the cartilage and meniscus. Despite the different surgical techniques, the general recommendation is for replacement of the ACL. Extensive procedures with an increased risk of epiphyseal injury should be avoided and anatomical techniques should be preferred. The results are good to very good and with adequate knowledge of the special features of children, complications are rare.

Coping With Anterior Cruciate Ligament Injury From Childhood to Maturation: A Prospective Case Series of 44 Patients With Mean 8 Years' Follow-up

BACKGROUND

There is no consensus regarding the best treatment approach for skeletally immature children with anterior cruciate ligament (ACL) injuries. High-quality studies with long-term follow-up are lacking, and evidence to support decision making is limited.

PURPOSE

To evaluate functional and patient-reported outcome, surgical history, and complications among young adults who sustained an ACL injury before the age of 13 years and were treated with active rehabilitation and the option of delayed ACL reconstruction if needed.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Forty-six children aged <13 years with a total intrasubstance ACL injury were included. None of these patients had additional injuries that warranted early surgery. At final follow-up at a mean 8 years after the time of injury, 44 patients remained in the study. The same test battery was conducted at baseline, 1 and 2 years, and final follow-up at approximately 18 years of age. The test battery included functional tests (hop tests and isokinetic muscle strength tests of quadriceps and hamstrings), patient-reported outcome measures (including the Knee injury and Osteoarthritis Outcome Score and the International Knee Documentation Committee Subjective Knee Form), and clinical examination. Medical records were reviewed to assess surgical history and complications.

RESULTS

At a mean 8 years of follow-up, 24 patients (55%) had undergone ACL reconstruction, and 16 (36%) had undergone meniscal surgery. Quadriceps muscle strength symmetry was >90% for 30 patients (68%). Mean leg symmetry indexes for hop and strength tests were consistently >90%, except for the single-hop test and hamstrings muscle strength for ACL-reconstructed knees. Mean ± SD International Knee Documentation Committee scores were 86.3 ± 13.7 for the ACL-reconstructed knees and 90.6 ± 11.8 for the nonreconstructed knees. At final follow-up, forty patients (91%) remained active in sports, but 29 (66%) restricted their activity level to nonpivoting sports.

CONCLUSION

Active rehabilitation may have a role in treatment of children with ACL injury. Approximately 50% of children may cope well, even to adulthood, without a surgical intervention. The other half may develop instability that warrants ACL reconstruction, and one-third may require meniscal surgery.

Treatment of ACL Tears in the Skeletally Immature Patient

The understanding and treatment of anterior cruciate ligament tears in skeletally immature patients continues to evolve. While conservative management was a mainstay of treatment, poor outcomes have led to several surgical techniques aimed at stabilizing the knee, optimizing outcome, and minimizing the chance of growth disturbance. Current techniques have, in large part, accomplished these goals but challenges remain. Looking to the future, different graft options, primary repair techniques, and rigorous prospective studies will help improve outcomes for this challenging patient population.

Outcomes of Physeal-Sparing ACL Reconstruction with Iliotibial Band Autograft in Skeletally Immature Prepubescent Children

BACKGROUND

Anterior cruciate ligament (ACL) tears are occurring in youth athletes with increasing frequency. Many ACL reconstruction procedures designed to allow for continued growth in patients with open physes have been described, but large series with mid- to long-term outcomes data are lacking. The purpose of the current study was to assess the clinical outcomes of a large cohort of prepubescent children who underwent a physeal-sparing, combined intra- and extra-articular ACL reconstruction with iliotibial (IT) band autograft over a 23-year period.

METHODS

Included in our analysis were 237 patients (240 knees) who underwent ACL reconstruction using IT band autograft at Tanner stage 1 or 2 (mean age of 11.2 ± 1.7 years). Physical examination data were analyzed for 225 of the 240 knees (mean follow-up, 25.8 months), and 137 (57%) of the knees had corresponding patient-reported clinical outcomes (patient-reported graft rupture and Pediatric International Knee Documentation Committee [Pedi-IKDC], Tegner activity scale, and Lysholm scores; mean follow-up, 6.2 years). Rates of growth arrest, IT band graft-harvest morbidity, and return to sports were analyzed.

RESULTS

Physical examination revealed that 96.8% of the knees were grade A on the Lachman test and 98.8% were grade A on the pivot-shift test. Graft rupture occurred in 9 (6.6%) of 137 knees, at an average of 33.5 months (range, 8.2 months to 8.0 years) postoperatively. For patients who did not sustain a graft rupture, the mean Pedi-IKDC score was 93.3 ± 11.0, the mean Lysholm score was 93.4 ± 9.9, and the mean score on the Tegner activity scale was 7.8 (mode, 7). While lateral thigh asymmetry at the IT band harvest site was noted by 48% of the subjects, only 1.6% reported associated pain. No cases of limb-length discrepancy or angular deformity were observed.

CONCLUSIONS

This procedure was associated with excellent functional outcomes, minimal risk of growth disturbance, and a low graft-rupture rate in skeletally immature prepubescent children. These results appear durable at mid- to long-term follow-up, at an average of >6 years postoperatively.

LEVEL OF EVIDENCE

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

Use of a Modified All-Epiphyseal Technique for Anterior Cruciate Ligament Reconstruction in the Skeletally Immature Patient

Background:

Multiple surgical approaches have been described for the management of anterior cruciate ligament (ACL) tears in skeletally immature patients.

Purpose:

To provide a detailed description of a modified all-epiphyseal ACL reconstruction and report early outcomes and complications with this new technique.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective review of all skeletally immature patients undergoing ACL reconstruction via a modified all-epiphyseal technique prior to July 2015 was performed. Skeletally immature male patients with a bone age of 8 to 15 years and female patients with a bone age of 8 to 12 years were selectively indicated for this procedure. The surgical technique involved an all-epiphyseal femoral tunnel drilled parallel and distal to the physis as well as an all-epiphyseal tibial tunnel. Both tunnels were placed in the anatomic footprint of the ACL. Tibial fixation was achieved first with a suspensory cortical fixation device followed by fixation on the femur with an interference screw.

Results:

During the study period, 30 patients with a mean bone age of 11.8 years underwent ACL reconstruction with this physeal-sparing technique; 26 patients (87%) achieved a minimum follow-up of 2 years. At final follow-up, the mean Lysholm score, Single Assessment Numeric Evaluation score, patient satisfaction, return-to-sport rate, and Tegner activity score were 93, 89, 9.2, 94%, and 7.6, respectively. Four graft failures (15%) and 3 (12%) contralateral ACL tears were identified. One patient was noted to have a 12-mm leg-length discrepancy at final follow-up, which required no additional treatment. No other leg-length discrepancies or angular deformities were identified.

Conclusion:

The modified all-epiphyseal ACL reconstruction technique achieved good functional outcomes, a high rate of return to sport, low failure rates, and low physeal injury rates at a mean follow-up of 3.2 years. Skeletally immature patients with an ACL tear requiring reconstruction pose a unique challenge for sports medicine clinicians. While several previous approaches have been described for this patient population, the proposed benefits of this new technique are that it is anatomic, it is physeal sparing, it uses osseous tunnels, and it provides good initial graft fixation strength.

Over 90 % of children and adolescents return to sport after anterior cruciate ligament reconstruction: a systematic review and meta-analysis

PURPOSE

To evaluate the rate at which children and adolescent athletes return to sporting activities after anterior cruciate ligament (ACL) reconstruction.

METHODS

Three databases, PubMed, MEDLINE, and EMBASE, were searched from database inception until September 9, 2017 by two reviewers independently and in duplicate. The inclusion criteria were English language studies that reported return to sport outcomes. Book chapters, conference papers, review articles, and technical reports were excluded. The rate of return to sports was combined in a meta-analysis of proportions using a random-effects model.

RESULTS

Overall, 20 studies with a combined total of 1156 ACL reconstructions met the inclusion criteria, with a mean age of 14.3 years (range 6-19) and a mean follow-up time of 6.5 years (range 1-22). All studies were level IV evidence (14 retrospective case series and 6 prospective case series). The pooled rate of return to any sport participation was 92.0% [95% confidence interval (CI), 86-96%]. The pooled rate of return to pre-injury level of sport was 78.6% (95% CI 71-86%) and that to competitive level of sport was 81.0% (95% CI 62-94%). A total of 93 of the 717 assessed athletes (13%) sustained re-injuries with graft ruptures, and in 91 of 652 patients (14%), contralateral ACL injuries were reported on final follow-up.

CONCLUSION

Pooled results suggest a high rate of return to sport following ACL reconstruction in children and adolescent athletes; however, this is associated with a relatively high rate of graft rupture and a similar rate of contralateral ACL injury. This study provides clinicians with evidence-based data on the ability of children and adolescent athletes to return to sport after ACL reconstruction, an important consideration for athletes of this population with ACL injuries.

LEVEL OF EVIDENCE

IV, systematic review of level IV studies.

Intrasubstance Anterior Cruciate Ligament Injuries in the Pediatric Population

Pediatric intrasubstance anterior cruciate ligament (ACL) tears have a significant epidemiologic impact as their numbers continue to grow globally. This review focuses on true pediatric intrasubstance ACL tears, which occur >400,000 times annually. Modifiable and non-modifiable risk factors include intercondylar notch width, ACL size, gender, landing mechanisms, and hormonal variations. The proposed mechanisms of injury include anterior tibial shear and dynamic valgus collapse. ACL tears can be associated with soft tissue and chondral defects. History and physical examination are the most important parts of evaluation, including the Lachman test, which is considered the most accurate physical examination maneuver. Imaging studies should begin with AP and lateral radiographs, but magnetic resonance imaging is very useful in confirming the diagnosis and preoperative planning. ACL injury prevention programs targeting high risk populations have been proven to reduce the risk of injury, but lack uniformity across programs. Pediatric ACL injuries were conventionally treated nonoperatively, but recent data suggest that early operative intervention produces best long term outcomes pertaining to knee stability, meniscal tear risk, and return to previous level of play. Current techniques in ACL reconstruction, including more vertically oriented tunnels and physeal sparing techniques, have been described to reduce the risk of physeal arrest and limb angulation or deformity. Data consistently show that autograft is superior to allograft regarding failure rate. Mean durations of postoperative therapy and return to sport were 7 ± 3 and 10 ± 3 months, respectively. These patients have good functional outcomes compared to the general population yet are at increased risk of additional ACL injury. Attempts at primary ACL repair using biological scaffolds are under investigation.