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

Midterm Outcomes of Hybrid Transepiphyseal ACL Reconstruction With Soft Tissue Quadriceps Tendon Autograft in Skeletally Immature Athletes

Background

Substantial developments in physeal-sparing surgical techniques for anterior cruciate ligament (ACL) reconstruction (ACLR) have demonstrated safety and efficacy in treating skeletally immature patients. However, outcomes using all-soft tissue quadriceps tendon (QT) autograft in this population are unknown.

Purpose

To evaluate outcomes including return to sport (RTS) and reinjury risk in skeletally immature patients ≥2 years after undergoing hybrid transepiphyseal ACLR using QT autograft.

Study Design

Case series; Level of evidence, 4.

Methods

A consecutive series of skeletally immature patients who underwent primary QT autograft ACLR using a hybrid transepiphyseal technique with ≥2 years of follow-up were retrospectively analyzed. Outcomes included RTS (primary), ability to return to preinjury level of competition, and subsequent ipsilateral/contralateral knee injury (secondary).

Results

A total of 50 patients were identified and contacted, of which 40 (80.0%) (35 male; mean age, 12.6 years [range, 9.4-16.0 years]) completed the survey at 5.7 ± 2.8 years (range, 2.0-11.5 years) postoperation. Of those, 26 (65.0%) were competitive middle/high school athletes and 18 (45.0%) competed in ≥2 sports. At a mean of 10.6 ± 2.3 months (range, 6-17 months) postoperatively, 37 patients (92.5%) returned to unrestricted sports participation, and 35 patients (87.5%) resumed competition at their preinjury level. Five patients required subsequent ipsilateral knee surgery for ACL revision (n = 2; 5.0%), meniscal injury (n = 2; 5.0%), or symptomatic hardware (n = 1; 2.5%) after a mean of 4.4 ± 1.7 years (range, 2.8-7.1 years). Three patients (7.5%) sustained a subsequent contralateral ACL injury, and 1 patient sustained a contralateral posterior cruciate ligament sprain.

Conclusion

Findings of this study suggest that midterm outcomes of patients treated with hybrid transepiphyseal ACLR using QT autograft are promising, with a high and expedited RTS and relatively low graft tear risk.

Anterior Cruciate Ligament Injury in Skeletally Immature Patients

The incidence of anterior cruciate ligament (ACL) injury continues to increase in the skeletally immature population. These injuries were historically treated with nonsurgical measures in this age group due to concerns for iatrogenic damage to the physis during ACL reconstruction. However, delayed surgery often led to recurrent instability, meniscal tears, and chondral damage. With the development of newer and safer surgical techniques with satisfactory outcomes, ACL reconstruction has become much more common in this age group. The patient's skeletal age is often used to determine remaining growth, which helps to decide the surgical technique chosen. These techniques include physeal sparing, partial transphyseal, and transphyseal surgical options, using soft-tissue autografts. Each technique has been shown to have favorable patient-reported outcomes, but no technique is without the risk of complications. This article will review the management of skeletally immature ACL injuries, including relevant anatomy, risk factors for injury, assessment of skeletal age, and different treatment options and outcomes.

The Double-Edged Sword: Anterior Cruciate Ligament Reconstructions on Adolescent Patients-Growth Plate Surgical Challenges and Future Considerations

The management of anterior cruciate ligament (ACL) injuries in pediatric patients presents unique challenges due to the presence of open growth plates in the proximal tibia and distal femur. Delaying ACL reconstruction until skeletal maturity may protect the physes but increases the risk of secondary injuries, such as meniscal tears and chondral damage, due to prolonged joint instability. Conversely, early surgical intervention restores knee stability but raises concerns about potential growth disturbances, including leg-length discrepancies and angular deformities. This narrative review examines current approaches to pediatric ACL management, highlighting the risks and benefits of both conservative and surgical treatments. Additionally, it explores the role of finite element modeling (FEM) as an innovative tool for pre-surgical planning. FEM offers a non-invasive method to optimize surgical techniques, minimize iatrogenic damage to growth plates, and improve patient outcomes. Despite its potential, FEM remains underutilized in clinical practice. This review underscores the need to integrate FEM into pediatric ACL care to enhance surgical precision, reduce complications, and improve long-term quality of life for young patients. By synthesizing available evidence, this review aims to provide clinicians with a comprehensive framework for decision-making and identify future directions for research in pediatric ACL reconstruction.

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.

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.

Management of Pediatric Anterior Cruciate Ligament Injuries: A Critical Analysis

» Overall evidence for the treatment of an anterior cruciate ligament (ACL) injury in a pediatric or skeletally immature patient remains lows.» An ACL reconstruction is recommended with concomitant repairable chondral and meniscus injury or with symptoms of persistent instability despite high-quality rehabilitation.» Treatment decision for pediatric ACL reconstruction should use a shared decision-making model weighing the risks and benefits of both a nonoperative vs. surgical treatment.

Imaging the pediatric anterior cruciate ligament: not little adults

An increased incidence of anterior cruciate ligament (ACL) injuries in children over the last few decades has led to a corresponding increase in ACL reconstruction procedures in children. In this review, we will illustrate unique features seen when imaging the ACL in children versus adults. After briefly reviewing relevant normal ACL anatomy, we will review imaging findings of congenital ACL dysplasia. This is followed by a discussion of imaging ACL avulsions. Lastly, we will review the different types of ACL reconstruction procedures performed in skeletally immature children and their post-operative appearances.

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.

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.

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.

[Management status of anterior cruciate ligament injury in children and adolescents]

OBJECTIVE

To summarize the current management of anterior cruciate ligament (ACL) injury in children and adolescents, in order to provide reference for the management of ACL injury in children and adolescents.

METHODS

The relevant literature at home and abroad in recent years was extensively accessed to summarize the management status of ACL injury in children and adolescent.

RESULTS

The number of ACL injury in children and adolescents is increasing every year. The diagnosis of ACL mainly depends on symptoms and signs. Rehabilitation, physeal-sparing techniques, partial transphyseal techniques, all-epiphyseal techniques, and transphyseal techniques are used to treat ACL injury in children and adolescents.

CONCLUSION

Dynamic monitoring of knee joint in children and adolescents should be strengthened. The best treatment for ACL injury in children and adolescents is selected according to the patients' actual age, bone age, Tanner stage, and physiological conditions such as menstruation, body growth speed, and other characteristics.

Allograft Medial Patellofemoral Ligament Reconstruction in Adolescent Patients Results in a Low Recurrence Rate of Patellar Dislocation or Subluxation at Midterm Follow-Up

PURPOSE

To evaluate rates of recurrent instability in adolescent patients with medial patellofemoral ligament (MPFL) reconstruction with allograft and associations of anatomic risk factors with complications.

METHODS

A retrospective review identified patients of a single surgeon who underwent MPFL reconstruction with allograft for recurrent patellar instability with minimum 2-year follow-up. Surgical management was recommended after a minimum 6 weeks of nonoperative management and included MPFL reconstruction with gracilis allograft using a double-bundle technique. Preoperative radiographs were evaluated to assess physeal closure, lower-extremity alignment, trochlear morphology, and Insall-Salvati and Caton-Deschamps ratios. Magnetic resonance images were reviewed to evaluate the MPFL, trochlear morphology, and tibial tubercle trochlear groove distance (TT-TG). Descriptive statistics were used to characterize data. The primary outcome was recurrent instability.

RESULTS

20 patients (24 knees; 18 knees in 14 females and 6 knees in 6 males; average age 15.7 years; range 11.5 to 19.6) underwent MPFL reconstruction with allograft (mean ± standard deviation follow-up 5.2 ± 1.7 years; range 2.2 to 8.1). Physes were open in 9 knees. The Insall-Salvati ratio was 1.09 ± 0.16, and the Caton-Deschamps index was 1.17 ± 0.15. Preoperatively, 19 patients were noted to have trochlear dysplasia, and TT-TG was 15.3 ± 3.9 mm. Three of 4 knees (16.7%) with non-hardware-related complications had open physes: 3 (12.5%) had recurrent instability, 2 of which underwent subsequent operation, and 1 sustained a patella fracture after a fall, requiring open reduction and internal fixation. The average Insall-Salvati ratio of these 4 patients was 1.21 ± 0.20, Caton-Deschamps index was 1.18 ± 0.17, and TT-TG was 17.5 ± 3.3 mm, none of which were statistically different from the group without complications. There were no clinically noted growth disturbances postoperatively.

CONCLUSIONS

MPFL reconstruction using allograft tissue may be performed safely in the pediatric and adolescent population with good outcomes at midterm follow-up, few complications, and a low rate of recurrent instability.

LEVEL OF EVIDENCE

IV, case series.

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.

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

Background

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

Purpose

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

Study Design

Cohort study; Level of evidence, 3.

Methods

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

Results

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

Conclusion

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

Association Between Knee Alignment and Meniscal Tear in Pediatric Patients with Anterior Cruciate Ligament Injury

BACKGROUND

The present study aimed to evaluate the association between elapsed time from anterior cruciate ligament (ACL) injury to surgical treatment and the incidence of meniscal tears in a cohort of patients ≤16 years old with varus-aligned and non-varus-aligned knees.

METHODS

The study cohort included 123 patients ≤16 years old who underwent primary ACL reconstruction between January 2016 and March 2020. Knee alignment was expressed as the hip-knee-ankle angle (HKAA), as measured preoperatively on an anteroposterior view of 3-dimensional computed tomography of the full length of the lower limb. Varus alignment was defined as an HKAA ≥181.0°, and non-varus alignment was defined as an HKAA <181.0°. Patients were divided into groups according to knee alignment and the elapsed time from injury to surgical treatment: early-treatment group (<60 days) and delayed-treatment group (≥60 days).

RESULTS

A total of 64 varus-aligned and 59 non-varus-aligned knees were identified. Among patients with varus-aligned knees, those in the delayed-treatment group showed a significantly lower rate of lateral meniscal tears (6 of 30, 20%) compared with those in the early-treatment group (17 of 34, 50%; p = 0.015). Among patients with non-varus-aligned knees, there was no significant difference in meniscal tears of any type between the early and delayed-treatment groups. Among patients without medial meniscal injury identified on initial magnetic resonance imaging, those with varus-aligned knees in the delayed-treatment group showed a significantly higher rate of medial meniscal tears at the time of the surgical procedure (8 of 20, 40%) compared with those with non-varus-aligned knees (1 of 18, 6%; p = 0.015).

CONCLUSIONS

Delayed ACL reconstruction in patients ≤16 years old with varus-aligned knees might be associated with an increased incidence of secondary medial meniscal tears. Accordingly, earlier ACL reconstruction in patients with varus-aligned knees should be considered.

LEVEL OF EVIDENCE

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

Effect of Static Alignment on Dynamic Knee Abduction Moments in Adolescent Athletes with Recent ACL Reconstruction

PURPOSE

Dynamic limb valgus, particularly high knee abduction moments, is a known risk factor for anterior cruciate ligament (ACL) injury and may result from poor static anatomic limb alignment, faulty biomechanics, or a combination of both. The purpose of this study was to assess the influence of static lower extremity anatomic alignment and dynamic kinematic/kinetic measures on knee abduction moments during sidestep cutting in adolescent athletes with recent ACL reconstruction.

METHODS

This retrospective study included 50 adolescents with recent unilateral ACL reconstruction (18/50 female, mean age = 15.8 yr, 7.6 months postsurgery). Frontal plane hip-to-ankle imaging was used to measure mechanical axis deviation and tibial-femoral angle. Three-dimensional motion capture provided lower extremity kinematics and kinetics during quiet standing and during the loading phase (initial contact to peak knee flexion) of an anticipated 45° sidestep cut. Imaging, static motion capture, and dynamic motion capture measures were investigated as potential predictors of average dynamic knee abduction moment using correlation and backward stepwise linear regression.

RESULTS

Dynamic knee abduction moment was best predicted by a combination of younger age and dynamic measures: trunk lean toward the planting limb, knee abduction and external rotation, and ankle inversion. Although static measures were correlated with dynamic knee abduction moment in univariate analysis, no static/anatomic variables entered the model once the dynamic measures were included.

CONCLUSION

Knee abduction moments during sidestep cutting were related to dynamic factors reflecting frontal and transverse plane motion. Static (anatomic) lower limb alignment did not influence knee abduction moments once these dynamic factors were considered. Knee abduction moments and ACL injury risk are therefore not dictated by anatomic alignment and can be altered through neuromuscular/biomechanical training.

Effect of a simple core muscle training program on trunk muscle strength and neuromuscular control among pediatric soccer players

Purpose

The purpose of this study was to examine the effect of simple core muscle training (CMT) program on trunk muscle strength and neuromuscular control among pediatric athletes.

Methods

Forty-nine male soccer players (mean age, 10.8 years) participated. The CMT program had three components (bench, side bench, and Nordic hamstrings) and was performed at least three times weekly for a year. Trunk flexion/extension muscle strength and the K/H ratio (determined by dividing knee separation distance by hip separation distance during drop-jump test and used as an index of lower limb valgus alignment) were measured, and the Y balance test (YBT) was performed before and after intervention. This study did not include the pure control group among the same team. To consider the effect of CMT on trunk muscle strength due to physical growth, we used the data of trunk muscle strength from the local cohort study previously conducted in our institution. One hundred participants who matched the age, height, body weight, and body mass index of the training group was designated as a control group.

Results

In the training group, the trunk flexion/extension strength significantly increased at 6 months (p < 0.001, p < 0.001, respectively) and 12 months (p < 0.001, p < 0.001, respectively) compared to initial value. The K/H ratio at initial contact and maximum knee flexion phase significantly increased at 6 months (p < 0.001 and p < 0.001, respectively); however, it did not increase at 12 months (p = 0.384 and p = 0.070, respectively) compared to the initial value. In the YBT, the maximized reach distance in each direction significantly increased after intervention on both the dominant and non-dominant sides, except in the posteromedial direction on the non-dominant foot. Compared to the control group, although there was no significant difference in trunk flexion/extension strength at baseline (p = 0.141 and p = 0.390, respectively), the training group showed significantly higher trunk flexion/extension muscle strength at 12 months (p < 0.001 and p < 0.001, respectively).

Conclusion

The CMT program increased trunk muscle strength and improved dynamic balance among pediatric male athletes.

Level of evidence

Level II

Revision ACL Reconstruction in Adolescent Patients

Background:

High failure rates have been documented after anterior cruciate ligament reconstruction (ACLR) in pediatric patients, and revision surgery is indicated due to high activity levels of children and adolescents.

Purpose:

To define trends in revision ACLR in patients who underwent initial ACLR at younger than 18 years.

Study Design:

Case series; Level of evidence, 4.

Methods:

An electronic medical record was used to retrospectively identify revision ACLR procedures performed by 2 surgeons between the years 2010 and 2016 in patients younger than 18 years at initial reconstruction. Descriptive information, intraoperative findings, surgical techniques, and rehabilitation data were recorded from initial and revision surgeries. Descriptive statistics were used.

Results:

A total of 32 patients (17 girls, 15 boys) met the inclusion criteria, with a mean age of 15.8 years at initial reconstruction. For initial reconstructions, 15 patients underwent transphyseal procedures, 3 patients underwent adult-type procedures using an anatomic reconstruction technique that did not take into account the physis, and 2 patients underwent partial intraepiphyseal procedures. Graft types included hamstring autograft (n = 17), allograft (n = 5), hybrid (n = 4), and bone–patellar tendon–bone autograft (BTB; n = 3). Average primary reconstruction graft diameter was 8.0 mm (girls, 7.72 mm; boys, 8.36 mm; P = .045). After initial reconstruction, 10 patients had postoperative protocol noncompliance, and 8 patients reported delayed recovery. Mean time to retear was 565 days (range, 25-1539 days). At revision, BTB autograft was used in 50% (n = 16), followed by hamstring autograph (31.3%; n = 10) and allograft (12.5%; n = 4); mean graft diameter was 9.05 mm. Chondral surgery was more common during revision (25% for revision vs 0% for index; P = .031). There were 4 patients who required staged reconstruction with bone grafting. At mean final follow-up of 29.5 months (SD, 22.2 months), there were 3 graft failures (9.4%) and 5 contralateral ACL ruptures (15.6%).

Conclusion:

Most patients with ACL graft failure were adequately treated with a single revision. Conversion from a soft tissue graft to a BTB autograft was the most common procedure. Infrequently, patients required staged reconstructions. Providers should have a high index of suspicion for associated intra-articular injuries resulting from graft failure in adolescent patients.

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.