Intraarticular stabilization after anterior cruciate ligament tear in children and adolescents: results 6 years after surgery

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.

Primary Proximal ACL Repair: A Biomechanical Evaluation of Different Arthroscopic Suture Configurations

Purpose: Several suture techniques have been described in the past for direct ACL repair with poor healing capacity and a high re-rupture rate. Therefore, we investigated a refixation technique for acute primary proximal ACL repair. The purpose of this study is to compare the biomechanical properties of different suture configurations using a knotless anchor. Methods: In this study, 35 fresh-frozen porcine knees underwent proximal ACL refixation. First, in 10 porcine femora, the biomechanical properties of the knotless anchor, without the ligament attached, were tested. Then, three different suture configurations were evaluated to reattach the remaining ACL. Using a material testing machine, the structural properties were evaluated for cyclic loading followed by loading to failure. Results: The ultimate failure load of the knotless anchor was 198, 76 N ± 23, 4 N significantly higher than all of the tested ACL suture configurations. Comparing the different configurations, the modified Kessler–Bunnell suture showed significant superior ultimate failure load, with 81, 2 N ± 15, 6 N compared to the twofold and single sutures (50, 5 N ± 14 N and 37, 5 ± 3, 8 N). In cyclic loading, there was no significant difference noted for the different configurations in terms of stiffness and elongation. Conclusions: The results of this in vitro study show that when performing ACL suture using a knotless anchor, a modified Kessler–Bunnell suture provides superior biomechanical properties than a single and a twofold suture. Within this construct, no failure at the bone–anchor interface was seen. Clinical relevance: Since primary suture repair techniques of ACL tears have been abandoned because of inconsistent results, ACL reconstruction remains the gold standard of treating ACL tears. However, with the latest improvements in surgical techniques, instrumentation, hardware and imaging, primary ACL suture repair might be a treatment option for a select group of patients. By establishing an arthroscopic technique in which proximal ACL avulsion can be reattached, the original ACL can be preserved by using a knotless anchor and a threefold suture configuration. Nevertheless, this technique provides an inferior ultimate failure load compared to graft techniques, so a careful rehabilitation program must be followed if using this technique in vivo.

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.

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).

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.

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.

Primary Arthroscopic Repair of the Anterior Cruciate Ligament: A Systematic Review of Clinical Outcomes

PURPOSE

To describe the clinical outcomes after primary arthroscopic anterior cruciate ligament (ACL) repair.

METHODS

A systematic review of the PubMed, Embase, and Cochrane Library databases was performed according to the PRISMA guidelines. All English-language literature published from 2000 to 2018 that reported the clinical outcomes after primary arthroscopic repair (AR) of complete tear of the ACL (without augmentation) with a minimum 2-year follow-up was reviewed by 2 independent reviewers. Outcomes included repair failure, reoperation, postoperative knee stability, and patient-reported outcomes. Descriptive statistics are presented. Study quality was evaluated with the Modified Coleman Methodology Score (MCMS) and the Methodological Index for Nonrandomized Studies (MINORS) score.

RESULTS

Six studies (2 level III, 4 level IV) were included. The mean MCMS was 62.2. The mean MINORS score for noncomparative studies was 11.8, and for comparative studies, 18. Six studies reported outcomes of 89 patients who underwent AR of the ACL from 2007 to 2016 (age, 8 to 67 years; follow-up, 24 to 110 months). All 6 studies included exclusively proximal avulsion tears. Overall, 0% to 25.0% of patients experienced repair failure (I² = 23.7%; 95% confidence interval, 0% to 67.6%), and 0% to 20.0% of patients had a subsequent reoperation (I² = 12.1%; 95% confidence interval, 0% to 77.7%). Similar inconsistent results were shown for postoperative knee stability measures and patient-reported outcomes.

CONCLUSIONS

The literature on clinical outcomes of primary arthroscopic ACL repair is limited. The reported rates of repair failure and reoperation are highly inconsistent. Most studies report relatively high failure rates.

LEVEL OF EVIDENCE

IV, systematic review of level III and IV studies.

Anterior Cruciate Ligament Repair Outcomes: An Updated Systematic Review of Recent Literature

PURPOSE

To critically review recent literature on outcomes following primary surgical repair of the anterior cruciate ligament (ACL).

METHODS

In December 2018, a search of the MEDLINE database was conducted for English language articles reporting clinical outcomes of ACL repair from 2003 to 2018. Included studies were evaluated for patient demographics, patient-reported outcome measures, return to sports/work, patient satisfaction, and postoperative complications. Subgroup analysis was conducted for studies that included patients with only type 1/proximal ACL ruptures.

RESULTS

Twenty-eight studies satisfied the inclusion criteria, comprising 2,401 patients (52.3% male, 35.7% female, 12.0% unspecified gender) with mean age ranging from 6.0 to 43.3 years. Most studies were conducted in Europe (82.1%), were level of evidence IV (60.7%), and were designed as case series (57.1%). Fourteen investigations (50.0%) used primary suture repair and 14 (50.0%) used dynamic intraligamentary stabilization. Preoperative ranges for Lysholm, International Knee Documentation Committee Score subjective, and Tegner scores were 28 to 100, 94.1 to 100, and 2 to 9, respectively. Postoperative ranges for the same measures were 80 to 100, 54.3 to 98, and 3.67 to 7, respectively. Time to return to sport/work ranged from 3.1 ± 3.3 to 17.4 ± 1.5 weeks. Frequency of rerupture, revision ACL surgery, and overall reoperations were as high as 23.1%, 33.3%, and 51.5%, respectively. Overall ACL repair survivorship ranged from 60.0% to 100.0%. In subgroup analysis for proximal ruptures treated with repair, the rates of revision ACL reconstruction (ACLR) and total reoperations were as high as 12.9% and 18.2%, respectively.

CONCLUSIONS

Based on our cumulative findings across 2,401 patients from the 28 included studies, it appears that ACLR results in better survivorship and patient-perceived postoperative improvement when compared with ACL repair. At present, ACLR appears to remain the superior treatment strategy in the vast majority of cases.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II to IV studies.

Transphyseal anterior cruciate ligament reconstruction in adolescents with substantial remaining growth causes temporary growth arrest resulting in subclinical leg-length discrepancy

The purpose of the present study was to investigate the characteristics of growth disturbances in patients with remaining growth after transphyseal anterior cruciate ligament (ACL) reconstruction who were confirmed to have no definite postoperative physeal abnormalities on magnetic resonance imaging (MRI).Forty adolescents (mean age 15.6 ± 1.0 years [range 12.2-16.8], mean follow-up 2.7 ± 0.7 years [range 2.0-5.5 years]), who underwent transphyseal ACL reconstruction and were confirmed to have no focal physeal disruptions on follow-up MRIs 6 to 12 months after the operation, were retrospectively evaluated. The patients were grouped according to the leg-length growth of the uninjured side, measured on scanograms, obtained before surgery, and at the final follow-up.Leg-length discrepancies (LLD) at the last follow-up were greater in patients with leg growth ≥4 cm than in those with leg growth <4 cm (5.3 ± 9.0 mm vs -0.3 ± 4.2 mm, P = .033); however, no significant difference was observed between subgroup patients with leg growth of 4 to 6 cm or ≥6 cm (5.6 ± 10.4 mm vs 4.8 ± 7.0 mm, P = .958). On multivariate analysis, leg growth was a significant predictive factor for the final LLD (P = .030).Adolescents with additional leg-length growth after transphyseal ACL reconstructions presented with greater LLDs (as shown in the <4 cm vs ≥4 cm groups), but they also presented a ceiling effect (as shown in the 4-6 cm vs ≥6 cm subgroups). Transphyseal ACL reconstructions appeared to cause temporary growth arrest/disturbances in patients with substantial remaining growth which then resumed resulting in clinically insignificant LLDs.

Is Anteromedial Drilling Safe in Transphyseal Anterior Cruciate Ligament Reconstruction in Adolescents with Growth Remaining?

BACKGROUND

Previous reports of transphyseal drilling in anterior cruciate ligament (ACL) reconstruction have demonstrated good clinical outcomes without subjective changes in further skeletal development. The purpose of this study is to evaluate radiographic changes during continued growth following a transphyseal ACL reconstruction using an anteromedial femoral (AM) drilling technique in patients with >18 months of growth remaining.

METHODS

A review of consecutive adolescents who underwent a soft tissue transphyseal ACL reconstruction using an AM drilling technique was performed. Inclusion criteria was 18 months of growth remaining based on radiographic bone age and standing radiographs at least one year from the index procedure. Demographic, preoperative, and postoperative data, and follow-up three-foot standing lower extremity radiographs were reviewed. Radiographic data included femoral length, tibial length, total lower extremity length, mechanical axis deviation (MAD), lateral distal femoral angle (LDFA), and medial proximal tibial angle (MPTA).

RESULTS

In total 12 adolescent patients with a mean age of 13.4 years (range, 12.3 to 14.4) and bone age of 13.4 years (11.5 to 14) at the time of surgery were included. At an average of 2.27-year follow-up (412 to 1058 d), there was no difference in the total growth of the operative and nonoperative limb (48.5 mm vs. 47 mm; P=0.36). In addition, the average increases in femoral length (23.4 mm) and tibial length (25.8 mm) were not statistically different between the operative and the nonoperative limb (P=0.12; P=0.75). There was no statistical difference in mechanical axis deviation, LDFA, or MPTA between preoperative and postoperative radiographs. Mean differences in operative and nonoperative coronal angular changes were all <1.5 degrees.

CONCLUSIONS

With at least 2 years of growth remaining, transphyseal ACL reconstruction with anteromedial drilling did not significantly affect the physis or residual growth compared with the contralateral extremity. Although this technique may create a larger defect in the physis, standing radiographs demonstrate there is no change in limb length or angulation in growing adolescents approximately 2 years after surgery.

LEVEL OF EVIDENCE

This is a case series; Level IV evidence.

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.

Is There a Role for Internal Bracing and Repair of the Anterior Cruciate Ligament? A Systematic Literature Review

BACKGROUND

Renewed interest has arisen in arthroscopic anterior cruciate ligament (ACL) repair techniques.

HYPOTHESIS

ACL repair with or without some form of internal bracing could lead to good outcomes in a carefully selected subset of patients.

STUDY DESIGN

Systematic review.

METHODS

An electronic database search was performed to identify 89 papers describing preclinical and clinical studies on the outcome of ACL repair.

RESULTS

Proximal ACL tear patterns showed a better healing potential with primary repair than distal or midsubstance tears. Some form of internal bracing increased the success rate of ACL repair. Improvement in the biological characteristics of the repair was obtained by bone marrow access by drilling tunnels or microfracture. Augmentation with platelet-rich plasma was beneficial only in combination with a structural scaffold. Skeletally immature patients had the best outcomes. Acute repair offered improved outcomes with regard to load, stiffness, laxity, and rerupture.

CONCLUSION

ACL repair may be a viable option in young patients with acute, proximal ACL tears. The use of internal bracing, biological augmentation, and scaffold tissue may increase the success rate of repair.

Anterior cruciate ligament reconstruction in skeletally immature patients : a systematic review

AIMS

Different methods of anterior cruciate ligament (ACL) reconstruction have been described for skeletally immature patients before closure of the growth plates. However, the outcome and complications following this treatment remain unclear. The aim of this systematic review was to analyse the outcome and complications of different techniques which may be used for reconstruction of the ACL in these patients.

MATERIALS AND METHODS

We performed a systematic review of the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. This involved a comprehensive search of PubMed, Medline, CINAHL, Cochrane, Embase and Google Scholar databases using the following combinations of keywords, "knee", "anterior cruciate ligament", "reconstruction", "injury", "children", "adolescent", "skeletally immature", "open physis" and "surgery".

RESULTS

A total of 53 studies met the inclusion criteria and were included for analysis. The overall rate of disturbance of growth after ACL reconstruction was 2.6%, with no statistical difference between transphyseal and physeal-sparing techniques. Physeal-sparing techniques had a lower rate of post-operative complications compared with transphyseal techniques (p = 0.0045). Outcomes assessed were Lysholm score, International Knee Documentation Committee (IKDC) score, the IKDC grade, the Tegner score and the KT-1000. Both techniques had similar clinical outcomes.

CONCLUSIONS

This review reveals low rates of disturbance of growth after ACL reconstruction in skeletally immature patients. Although limited, the available evidence did not support any particular surgical technique when considering disturbance of growth or clinical outcome. Further randomised controlled trials are needed to investigate the efficacy of differing surgical techniques on outcomes in skeletally immature patients. Cite this article: Bone Joint J 2017;99-B:1053-60.

Arthroscopic anterior cruciate ligament repair for proximal anterior cruciate ligament tears in skeletally immature patients: Surgical technique and preliminary results

BACKGROUND

Anterior cruciate ligament (ACL) tears in children are increasingly common and present difficult treatment decisions due to the risk of growth disturbance. Although open primary ACL repair was abandoned in the historical literature, recent studies have suggested that there is a role for arthroscopic primary repair in patients with proximal tears.

METHODS

This is a retrospective review of five consecutive patients aged 9.2years (range 8 to 10) who underwent suture anchor ACL reinsertion. Patients were included if they were Tanner stages 1-2 and proximal ACL tears with adequate tissue quality confirmed arthroscopically. The time frame was 81days. Arthroscopic ACL reinsertion was performed with bioabsorbable suture anchor. Clinical evaluation, KT-1000™, and MRI were re-evaluated. Clinical outcomes were measured using International Knee Documentation Committee (IKDC), Lysholm and Tegner activity score.

RESULTS

At a mean follow-up of 43.4months (range 25 to 56), no re-injury and leg length discrepancies were observed. Four patients had negative Lachman tests. The remainder had a grade 1 Lachman test. The mean side-to-side difference was 3 (2-4mm). In MRI obtained at the last follow-up, no articular lesions or growth arrest were observed and the reinserted ACL was recognized in every exam. All patients returned to previous level of activity and presented normal and nearly normal IKDC score. The mean Lysholm score was 93.6.

CONCLUSION

Arthroscopic ACL repair can achieve good short-term results with joint stability and recovery of sport activity in skeletally immature patients, with proximal ACL avulsion tear.

Rare ACL enthesis tears treated by suture in children. A report of 14 cases after a mean 15 years follow-up

INTRODUCTION

ACL enthesis tears are rare in children and there are very few reports in the literature. Characterized by avulsion of the ligament that tears off a very thin piece of cartilage or a bone fragment at the ACL epiphyseal insertion site, we hypothesize that conservative treatment by suture could reduce the number of patients requiring later ligament reconstruction.

MATERIALS AND METHODS

Fourteen patients underwent surgery between 1986 and 2014 and were included in this retrospective study. Patients were selected according to the following criteria: suture failure requiring ligament reconstruction, reoperation-free survival for secondary injury and the subjective and objective IKDC scores by comparative laximetry.

RESULTS

After almost 15 years of mean follow-up, reoperation-free survival was approximately 85%. Three patients required one or more additional surgeries; one for suture failure requiring 2 additional ligament reconstructions, one for a meniscal tear with a mechanical block requiring partial meniscectomy and one patient with secondary pain requiring arthroscopic surgery that was inconclusive.

DISCUSSION

Rare and often misdiagnosed, ACL enthesis tears in children can be treated by suture with satisfactory results. Careful analysis of plain films and an X-ray centered on the intercondylar notch often provide the diagnosis. In case of doubt, MRI, which is now more accessible, can prevent missing this entity. Improved standard surgical techniques and careful patient selection could make conservative treatment an option once again while avoiding the risks associated with ligament reconstruction technique.

LEVEL OF EVIDENCE

4.

Complications after epiphyseal reconstruction of the anterior cruciate ligament in prepubescent children

PURPOSE

Reconstruction of the anterior cruciate ligament (ACL) remains a major concern in the prepubescent, skeletally immature patient with wide open growth plates. Different surgical techniques have been proposed. This study reports the results and complications of ACL reconstruction in young children using an all epiphyseal technique.

METHODS

Between 2006 and 2010, 12 patients (10-13 years, median 12.1 years) underwent epiphyseal primary ACL reconstruction, with a total of 13 knee procedures. Patients were assessed retrospectively with a median follow-up of 54 months (range 39-80 months) consisting of a clinical examination, instrumented arthrometer testing and radiological analysis. Functional status was assessed using the Lysholm knee score, Tegner activity scale and IKDC-2000 form.

RESULTS

According to the IKDC examination form, five knees were rated as normal, six near normal and two abnormal. The median IKDC score at follow-up was 88.5 points (range 75-99 points). The mean side-to-side difference in KT-1000 ligament laxity testing was 1.5 mm (±2.5 mm). In two patients, reoperation was necessary due to graft failure. Two patients developed significant leg length inequality; one with 20 mm overgrowth and varus malalignment after re-reconstruction and the second developed arthrofibrosis and overgrowth of 16 mm. Four patients had minor limb length discrepancy ranging between +5 and +10 mm; no growth arrest was noted. One patient with an intact but slightly elongated graft required a meniscal suture 34 months after ACL reconstruction following a traumatic medial meniscal lesion.

CONCLUSION

Despite using the epiphyseal technique in ACL reconstruction, relevant growth discrepancy can occur. Thereby, overgrowth rates appear to potentially pose a major clinical problem, which has remained unreported so far. Overall, there is a considerable high risk of complications in this patient group.

LEVEL OF EVIDENCE

IV.

Primary Repair of the Anterior Cruciate Ligament: A Systematic Review

PURPOSE

To describe the clinical and preclinical research conducted on primary repair of the anterior cruciate ligament (ACL) during the past 10 years.

METHODS

A systematic search of PubMed, the Cochrane Central Register of Controlled Trials, and Embase was performed for all English-language studies published between 2003 and April 2014 on primary repair of the ACL.

RESULTS

Twenty-six studies met the inclusion and exclusion criteria. In the clinical research group, 8 studies (166 patients; age range, 10 to 71 years) met the inclusion and exclusion criteria and were largely long-term clinical outcome studies, based on the original cohorts from the 1970s and 1980s, and suggested high failure rates, additional surgery, and revision for instability. A subset of patients, however, achieved good to excellent subjective and objective long-term outcomes. In the preclinical research group, 18 studies met the inclusion and exclusion criteria and were based on an ACL transection model; they suggested that (1) stabilization of the knee with an internal suture strut improved the healing and biomechanical properties of the repaired ACL, (2) "enhancing" the repair with biological collagen-platelet composite augmentation improved healing and mechanical strength, (3) younger age and skeletal immaturity seem to correlate with improved histologic healing and biomechanical properties, (4) enhanced primary repair of the ACL may reduce post-traumatic osteoarthritis, and (5) the native ACL biomechanically outperformed the repaired ACL.

CONCLUSIONS

Although long-term human studies suggest collectively unacceptable outcomes for open primary repair of the ACL, a subset of patients achieved acceptable long-term results. ACL transection model animal studies showed improved healing and biomechanics with primary suture repair stabilization, early intervention, biological augmentation techniques, and younger age. Primary repair of the ACL may be an effective treatment modality for an appropriately selected subset of patients.

LEVEL OF EVIDENCE

Level IV, systematic review of preclinical and clinical Level IV studies.

Transphyseal anterior cruciate ligament reconstruction in patients with open physes: 10-year follow-up study

BACKGROUND

The treatment of anterior cruciate ligament (ACL) injuries in skeletally immature patients is controversial. Current evidence supports the view that surgical techniques restore knee stability and prevent progressive articular damage. However, most of the studies on this topic are small case series or they have short- or medium-term follow-up times.

PURPOSE

To determine the long-term functional outcomes and secondary complications of transphyseal intra-articular ACL reconstruction with hamstring graft in skeletally immature patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Transphyseal ACL reconstruction with autograft hamstrings was performed in 27 skeletally immature patients. The average age at surgery was 13 years (range, 12-16 years), and the average follow-up time was 10.6 years (range, 10-13 years). Clinical outcomes were assessed with preoperative and final follow-up Tegner, International Knee Documentation Committee (IKDC) subjective, and Lysholm scores. Surgery details, return to sports, and ACL reconstruction failures were collected. The anteroposterior knee laxity was assessed by arthrometry, and the presence of deformities and lower limb length discrepancies were evaluated by radiographs. The presence of degenerative signs on anteroposterior and lateral knee radiographs at final follow-up was also evaluated.

RESULTS

Transphyseal ACL reconstruction was performed with vertically oriented tunnels, 7 to 10 mm in diameter, using semitendinosus-gracilis autograft. The average preoperative Tegner, IKDC, and Lysholm scores were 7, 55, and 40, respectively. Significant differences in these scores were observed at the time of the final assessment (Tegner, 6 [P = .026]; IKDC, 94 [P < .001]; Lysholm, 92 [P < .001]). Two patients reported instability during sports activity. Three patients had a rupture of the ACL graft. No leg length discrepancy, axis malalignment, or degenerative changes were observed.

CONCLUSION

The transphyseal ACL reconstruction in skeletally immature patients is a safe option, with high functional and satisfaction results, without significant growth plate damage in this series of patients.

Risk for Revision After Anterior Cruciate Ligament Reconstruction Is Higher Among Adolescents: Results From the Danish Registry of Knee Ligament Reconstruction

Background:

The number of children and adolescents with anterior cruciate ligament (ACL) reconstructions is increasing, and disturbing reports on high rerupture rates in this group have been noted.

Purpose:

To describe the outcome of ACL reconstruction in children and adolescents based on data from the Danish Knee Ligament Reconstruction Registry (DKRR).

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Data were retrieved from the DKRR, a national population-based registry. The analysis was based on a population of 14,806 ACL-reconstructed patients. The outcome was evaluated using risk of ACL revision, subjective outcome score (Knee injury and Osteoarthritis Outcome Score [KOOS]), Tegner function score, and objective knee laxity. Three age groups were defined (A, <13 years; B, 13-15 years; and C, 15-20 years) and compared with D, patients ≥20 years (adults). There were 95 patients in group A, 327 in B, 2888 in C, and 11,496 in D.

Results:

There was a significantly increased risk of revision surgery in the age groups B (6.7%) and C (4.9%) compared with the adults in group D (2.0%). Objective knee laxity did not differ between the 4 groups. Groups A, B, and C had a higher score on the combined KOOS symptoms, pain, sport, and quality of life subscales (KOOS4; 79.6, 76.6, and 73.1, respectively) compared with the adults (69.7). Group B had higher KOOS quality of life (76.6) and sports (71.1) scores than did group C (73.1 and 66.4, respectively). The Tegner activity score did not differ between the 4 groups. No impact of the use of extracortical graft fixation was detected in the youngest age group.

Conclusion:

Study results indicated an increased risk of graft failure in patients between 13 and 20 years of age. This is in contrast to the better subjective and equal objective knee score found in the same age groups.

Clinical Relevance:

The new knowledge about the high revision rate among ACL-reconstructed teenagers is important for evidence-based preoperative information of ACL patients and their parents.

The outcomes after anterior cruciate ligament reconstruction in adolescents with open physes

PURPOSE

We evaluated the clinical outcome of anterior cruciate ligament reconstruction (ACLR) in adolescents with open physes and compared those results with adults.

MATERIALS AND METHODS

Fifteen adolescents with open physes underwent physeal-sparing double-bundle ACLR using hamstring autograft. The median age of the adolescents was 14 years (range 13-16 years). Forty adults underwent anatomic double-bundle ACLR during the same period of this study. The median age of the adults was 26 years (range 17-39 years). Clinical outcomes were evaluated in terms of manual Lachman test, pivot shift test and the results of KT-2000 arthrometer. Additionally, we evaluated clinical outcome in terms of International Knee Documentation Committee (IKDC) score and Lysholm Knee Scoring Scale. We also evaluated rates of re-rupture.

RESULTS

No clinically significant growth abnormalities were observed in adolescent cases. In the Lachman test, two of the 15 adolescents had a positive, whereas one of the 40 adults had a positive (n.s.). In the pivot shift test, three of the 15 adolescents had a positive, whereas two of the 40 adults had a positive (n.s.). There was no statistically significant difference between adolescents and adults, in the mean side-to-side difference in KT-2000 measurements (1.5 ± 1.5 mm vs. 1.1 ± 1.9 mm: n.s.), the median IKDC score (96.7 vs. 97.3: n.s.) and Lysholm Scale (99 vs. 98: n.s.), rates of re-rupture (13.3 vs. 7.5 %: n.s.).

CONCLUSION

Physeal-sparing ACLR with hamstring autograft in adolescents with open physes resulted in good clinical outcomes similar to those of ACLR in adults without growth abnormalities.

Transphyseal anterior cruciate ligament reconstruction in the skeletally immature: follow-up to a minimum of sixteen years of age

BACKGROUND

The evidence in favor of early surgical treatment of anterior cruciate ligament (ACL) injuries in children is increasing. However, the controversy regarding the safety of such a procedure in young athletes with wide open physes remains unresolved.

METHODS

We reviewed prospectively collected outcome data on consecutive patients who had undergone transphyseal ACL reconstruction at either (1) an age of less than fourteen years and Tanner stage 1 or 2, or (2) an age of less than twelve years and Tanner stage 3. Children who had less than four years of follow-up, who were younger than sixteen years at the time of final follow-up, or who had been at Tanner stage 4 at the time of surgery were excluded. Twenty-eight of the thirty-two included patients had been at Tanner stage 1 or 2 at the time of surgery, and the remaining four had been at Tanner stage 3 but had been younger than twelve years of age. The mean age at the time of the surgery was 11.25 years (range, 9.5 to 14.0 years; median, 12.1 years). The mean duration of follow-up was 72.3 months (range, forty-eight to 129 months; median, seventy-two months).

RESULTS

The mean Lysholm score improved from 71.5 preoperatively to 95.86 postoperatively (p < 0.0001). The mean Tegner activity scale score improved from 4.03 to 7.66 (p < 0.0001), which was comparable with the preinjury score of 8.0. One patient had a mild valgus deformity with no functional disturbance, and none had a limb-length discrepancy. One rerupture occurred, but all other patients had a good or excellent outcome.

CONCLUSIONS

This case series indicates good long-term results of ACL reconstruction with use of a transphyseal technique in young children.

The current evidence for treatment of ACL injuries in children is low: a systematic review

BACKGROUND

There is no consensus on the management of anterior cruciate ligament (ACL) injuries in skeletally immature children, and the methodological quality of published studies is questionable. The transphyseal reconstructions, physeal-sparing reconstructions, and nonoperative treatment algorithms that are advocated have little support in the literature. The purpose of this study was to systematically review the methodological quality of the literature on the management of ACL injuries in skeletally immature children.

METHODS

We performed a literature search with use of PubMed to identify prospective or retrospective studies whose primary aim was to assess the outcome after operative or nonoperative treatment of ACL injuries in skeletally immature children. To be included in the analysis, a study had to have a mean duration of follow-up of at least two years and a minimum of ten children in the study had to be verified to be skeletally immature. The methodological quality of the included studies was evaluated with use of the Coleman Methodology Score.

RESULTS

No randomized controlled trials, two prospective cohort studies, and twenty-nine retrospective studies met the inclusion criteria. The Coleman Methodology Score averaged 44.7 ± 9.2 out of 100 (range, 28 to 62). The methodological deficiencies were most evident with regard to the number of included children, the study design, and the description of rehabilitation protocols, outcome criteria, and outcome assessments.

CONCLUSIONS

Caution is necessary when interpreting the results of studies on the treatment of ACL injuries in skeletally immature children because of widespread methodological deficiencies. There is a need for appropriately sized prospective studies and detailed descriptions of rehabilitation programs.

Management of anterior cruciate ligament injuries in skeletally immature individuals

Anterior cruciate ligament (ACL) injuries in skeletally immature individuals remain a challenge for the child, the parents, orthopaedic surgeons, and physical therapists. The main challenges are the potential risk of recurrent instability, secondary injuries following nonoperative treatment, and the risks involved with surgical treatment due to the vulnerability of the epiphyseal growth plates. We first present the physiological background for considerations that must be made when advising on treatment alternatives for skeletally immature individuals after ACL injury. The implications of continuous musculoskeletal development for treatment decisions are emphasized. No randomized controlled trials have been performed to investigate outcomes of different treatment algorithms. There is no consensus in the literature on clinical treatment decision criteria for whether a skeletally immature child should undergo transphyseal ACL reconstruction, physeal sparing ACL reconstruction, or nonoperative treatment. Additionally, well-described rehabilitation programs designed for either nonoperative treatment or postoperative rehabilitation have not been published. Based on the currently available evidence, we propose a treatment algorithm for the management of ACL injuries in skeletally immature individuals. Finally, we suggest directions for future prospective studies, which should include development of valid and reliable outcome measures and specific rehabilitation programs.

Pediatric anterior cruciate ligament reconstruction

An increasing number of anterior cruciate ligament (ACL) injuries are seen in children now than in the past due to increased sports participation. The natural history of ACL deficient knees in active individuals, particularly in children is poor. Surgical management of ACL deficiency in children is complex due to the potential risk of injury to the physis and growth disturbance. Delaying ACL reconstruction until maturity is possible but risks instability episodes and intra-articular damage. Surgical options include physeal-sparing, partial transphyseal and complete transphyseal procedures. This article reviews the management of ACL injured skeletally immature patients including the functional outcome and complications of contemporary surgical techniques.

Physeal-sparing reconstruction of anterior cruciate ligament tears in children: results of 57 cases using patellar tendon

This study evaluated the results of a physeal-sparing technique of intra-articular anterior cruciate ligament (ACL) reconstruction in skeletally immature patients, with particular reference to growth disturbance. Between 1992 and 2007, 57 children with a mean age of 12.2 years (6.8 to 14.5) underwent ACL reconstruction using the same technique. At a mean of 5.5 years (2 to 14) after surgery, 56 patients underwent clinical and radiological evaluation. At that time, 49 patients (87.5%) had reached bony maturity and 53 (95%) achieved A or B according to the IKDC 2000 classification. Four patients had stopped participation in sports because of knee symptoms, and three patients (5.4%) had a subsequent recurrent ACL injury. There was no clinical or radiological evidence of growth disturbance after a mean growth in stature of 20.0 cm (3 to 38). This study demonstrates that ACL reconstruction sparing the physes in children is a safe technique protecting against meniscal tears and giving better results than reconstruction in adults, without causing significant growth disturbance.

Transphyseal anterior cruciate ligament reconstruction in a skeletally immature knee using anterior tibialis allograft

Anterior cruciate ligament (ACL) injury in the skeletally immature individual is being recognized with increasing frequency. Nonoperative treatment of ACL injuries in skeletally immature patients have not been favorable. Surgical treatment options for complete ACL tears include primary ligament repair, extraarticular tenodesis, transphyseal reconstruction, partial transphyseal reconstruction, and physeal-sparing reconstruction. The advantage of transphyseal reconstruction is placement of the graft tissue in an isometric position, which provides better results, according to the literature. The potential disadvantage is angular or limb-length discrepancy caused by physeal violation. Controversy exists in allograft selection about whether bone or soft tissue passes into physes. The use of standard tunnels provides reliable results, but carries the risk of iatrogenic growth disturbance from physeal injury.This article presents 4 cases of transphyseal ACL reconstruction using anterior tibialis allograft in skeletally immature patients that had satisfactory functional outcomes with no growth disturbances. This is the first report of transphyseal ACL reconstruction using anterior tibialis allograft in skeletally immature patients in the English-speaking literature. All patients underwent transphyseal ACL reconstruction using anterior tibialis tendon allograft. None of the patients had angular deformities. No early physeal arrest was measured between the preoperative and postoperative radiographs. At last follow-up, the results of the Lachman test were normal for 3 patients and nearly normal for 1 patient. All patients demonstrated full range of knee motion (comparing the reconstructed knee to the contralateral knee). The results of the pivot-shift test were normal for 3 patients and nearly normal for 1 patient. No patients reported giving way.

Intraarticular stabilization following anterior cruciate ligament injury in children and adolescents

PURPOSE

Significant controversy exists regarding the potential harm to the growth plate following reconstruction of the anterior cruciate ligament in skeletally immature patients. This study was performed to evaluate the results of a transepiphyseal replacement of the anterior cruciate ligament in skeletally immature patients.

METHODS

Ninety-four skeletally immature patients (56 male and 38 female) with median age 13.7 years (range, 11.6-15.9 years) who underwent arthroscopic transphyseal reconstruction of anterior cruciate ligament with four-strand medial hamstring autograft between 1999 and 2006 were reviewed. All patients had been followed up until skeletal maturity was confirmed.

RESULTS

The average follow-up was 38 months (range 24-60 months). Neither leg length discrepancy nor angular deformities were noted on radiological or clinical measurement. Two patients had radiographic evidence of mild arthrosis at final follow-up. New traumatic injuries occurred in 4 patients, in whom surgical revision was performed. Ligament laxity testing with a KT 1000/2000 arthrometer showed no significant difference between the normal and the operated legs. At follow-up, the median Lysholm score was 89 (range 77-100), and the median Tegner activity score was increased from 3 to 6. The International Knee Documentation Committee score was A in 79 patients (84%) and B in 6 patients (6%) and C in 9 patients (9%). Of the 94 patients, 73 (78%) returned to their similar preoperative sport activities and 90% returned to their preoperative level of daily activities.

CONCLUSIONS

ACL reconstruction with medial hamstring autograft via transepiphyseal drilling and grafting yielded satisfactory clinical results with no growth defects in skeletally immature patient. The preliminary results of this series demonstrated that this surgical technique can be performed in prepubescent patients with efficacy and safety.

LEVEL OF EVIDENCE

IV.

Good surgical outcome of transphyseal ACL reconstruction in skeletally immature patients using four-strand hamstring graft

PURPOSE

Our purpose was to evaluate the clinical and radiological outcome at maturity of an « adult-like » transphyseal anterior cruciate ligament (ACL) reconstruction performed in skeletally immature patients using four-strand hamstring graft.

METHODS

The records of all skeletally immature patients who underwent transphyseal ACL reconstruction between 2004 and 2006 at our institution were reviewed. Inclusion criteria were age less than 16 years and radiographic evidence of open physes. Thirty-eight children and prepubescents were identified. All underwent postoperative clinical evaluation with International Knee Documentation Committee scores and long leg radiographs. Each patient was followed up until skeletal maturity was confirmed.

RESULTS

Twenty-eight patients were scored A, four B, and five D according to IKDC. At last follow-up, there was no radiographic evidence of malalignment in any of the patients. Five underwent a reoperation. Three patients suffered traumatic graft disruption and two from post-operative knee instability.

CONCLUSION

Early operative treatment by means of the quadruple hamstring free graft appears to be a safe and relevant procedure for ACL reconstruction even in skeletally immature patients.

Surgical techniques and outcomes after anterior cruciate ligament reconstruction in preadolescent patients

PURPOSE

To determine whether any anterior cruciate ligament (ACL) reconstruction technique is clinically superior in skeletally immature patients with wide-open physes.

METHODS

We searched Medline and Embase from 1966 to mid July 2009. Inclusion criteria required clinical studies of ACL reconstructions to define skeletally immature patients as having at least 1 of the following criteria: (1) chronologic age of less than 15 years in boys or less than 14 years in girls; (2) bone age of less than 15 years in boys or less than 14 years in girls; (3) Tanner stage I, II, or III; and (4) at least 10 cm of total growth after the reconstruction. Thirteen case series were identified and were evaluated for patient characteristics, surgical technique, clinical outcomes, and bone growth results.

RESULTS

Four studies used physeal-sparing techniques. Six studies used transphyseal techniques. Two studies used a combined technique, and a multicenter study reported results of both techniques. Within the physeal-sparing group, there were 2 studies that used an entirely extra-epiphyseal technique and 2 studies that used intra-epiphyseal techniques. Overall clinical outcomes were excellent, with growth complications being very rare in all of these series.

CONCLUSIONS

Both physeal-sparing and transphyseal reconstructions can produce excellent clinical outcomes with a very low incidence of growth complications in Tanner stage II and III patients. Tanner stage I patients had excellent clinical results with physeal-sparing techniques (both extra- and intra-epiphyseal techniques). Not enough Tanner stage I patients underwent transphyseal techniques to support or discourage their use. This evidence supports considering the expansion of transphyseal reconstruction indications from Tanner stage IV patients to Tanner stage II and III patients. More studies evaluating transphyseal techniques in Tanner stage I patients are needed at this time.

LEVEL OF EVIDENCE

Level IV, systematic review.

Outcomes and risks of operative treatment of rupture of the anterior cruciate ligament in children and adolescents

PURPOSE

The aim of this meta-analysis was to evaluate the clinical outcomes and risks of anterior cruciate ligament (ACL) surgery in children and adolescents.

METHODS

We electronically searched Medline, the Cochrane Controlled Trial Database, Embase, and Medpilot for studies on surgical treatment for ACL ruptures in skeletally immature patients. We extracted baseline demographics, follow-up intervals, surgical details (i.e., ligament suture or reconstruction, physeal-sparing or transphyseal techniques, type of transplant, and methods of fixation). Endpoints comprised rates of growth disturbances and reruptures, as well as knee function (measured by the International Knee Documentation Committee's documentation system and the Lysholm score). Unweighted overall effect sizes (risks, risk ratios [RRs], and means of functional scores) were estimated by use of crude nominators and denominators, and random-effects meta-regression analysis was used for weighted data synthesis.

RESULTS

A total of 55 articles reporting on 935 patients (median age, 13 years; range, 1.5 to 16 years) were suitable for the study. After a median follow-up of 40 months (range, 14 to 89 months), the weighted rate of leg-length differences or axis deviations was 1.8% (95% confidence interval [CI], 0% to 3.9%] and that of reruptures was 4.8% (95% CI, 2.9% to 6.7%). Excellent or good function (International Knee Documentation Committee grade A or B) was achieved in 84.2% (95% CI, 75.8% to 92.6%) of all knees, and Lysholm scores averaged 96.3 (95% CI, 95.5 to 97.2). Transphyseal reconstruction was associated with a significantly lower risk of leg-length differences or axis deviations compared with physeal-sparing techniques (1.9% v 5.8%; RR, 0.34; 95% CI, 0.14 to 0.81) but had a higher risk of rerupture (4.2% v 1.4%; RR, 2.91; 95% CI, 0.70 to 12.12). Sutures did not result in any growth disturbances, with a weighted rerupture rate of 4.6% (95% CI, 2.6 to 6.7). Fixation far from the joint line fared better than close fixation with regard to this endpoint (1.4% v 3.2%; RR, 0.42; 95% CI, 0.09 to 1.93). Bone-patellar tendon-bone grafts, which are also less likely to fail, were associated with higher risks of leg-length differences or axis deviations than were hamstrings (3.6% v 2.0%; RR, 1.82; 95% CI, 0.66 to 5.03). Meta-regression did not show a significant impact of the publication year on event rates.

CONCLUSIONS

This meta-analysis showed low rates of leg-length differences or axis deviations and graft failures after ACL reconstruction in skeletally immature patients. Hamstring transplants may lower the risk of leg-length differences or axis deviations, and physeal-sparing techniques may increase the risk. Randomized controlled trials are needed to clarify important issues in managing ACL ruptures in children and adolescents.

LEVEL OF EVIDENCE

Level IV, meta-analysis of case series.

No bone tunnel enlargement in patients with open growth plates after transphyseal ACL reconstruction

Bone tunnel enlargement after ACL reconstruction has been described extensively in adults. However, little is known about this phenomenon in patients with open growth plates. Thus, the goals of the current study were to evaluate changes in bone tunnel size in patients with open growth plates after transphyseal ACL reconstruction with suspensory fixation and to correlate tunnel size with clinical outcome after medium-term follow-up. Fourteen patients with open growth plates were included that underwent primary transphyseal ACL reconstruction using hamstrings autografts and suspensory fixation. Mean follow-up time was 7 years. At the time of follow-up, MRIs of the operated knee were performed, and outcome was assessed using KOS-ADLS, Lysholm score, IKDC Subjective Knee Form score, Knee Examination Form score, and KT-1000 measurements. On MRI, the cross-sectional area of the bone tunnels was assessed using special axial cuts perpendicular to the axes of the tunnels. Two orthopaedic surgeons and two radiologists analysed the MRIs. Change in bone tunnel size from surgery to follow-up was calculated. No significant changes in bone tunnel size from surgery to follow-up were found. Regarding outcome measures, KOS-ADLS averaged 95%, Lysholm Score averaged 96 points, IKDC Subjective Knee Form averaged 95%, IKDC Knee Examination Form scores were 8A, 5B, 1C, and KT-1000 measurements averaged 1.8 ± 1.4 mm. No significant correlations were found between tunnel size at follow-up and outcome measures. Based on our study, bone tunnel enlargement does not occur in patients who have open growth plates and undergo ACL reconstruction using suspensory fixation.

Valgus and flexion deformity after reconstruction of the anterior cruciate ligament in a skeletally immature patient

Anterior cruciate ligament reconstruction in children with open physes is still a topic of debate. We report a unique case of growth disturbance in valgus and flexion of the distal femoral epiphysis, after an ACL reconstruction in a 14.5-year-old boy. The Clocheville technique using the patellar tendon was performed. The femoral tunnel and tibial groove were both positioned above the growth plates. Eighteen months after ACL reconstruction, the patient had to be re-operated on for a valgus and flexion deformity of the femoral epiphysis. The clinical, radiological and aesthetic results were satisfactory. The angular deformity was caused by the fact that either the femoral tunnel was too close to the posterolateral femoral growth plate or an excessive eccentric traction of the graft in relation to the central point of the knee.

Rupture of the anterior cruciate ligament in children: early reconstruction with open physes or delayed reconstruction to skeletal maturity?

The purpose of this study was to compare two different strategies of management for ACL rupture in skeletally immature patient. In group 1, patients were treated in a children hospital by ACL reconstruction with open physis. In group 2, patients were treated in an adult hospital by delayed reconstruction at skeletal maturity assessed radiologically. Fifty-six consecutive patients were included in this retrospective study. Mean time from injury to surgery in group 1 and 2 was, respectively, 13.5 and 30 months. Patients from group 2 exhibited a higher rate of medial meniscal tears (41%) compare to group 1 (16%) and higher rate of meniscectomy. Both groups had the same rate of lateral meniscal tears. A temporary tibial valgus deformity was reported which was subsequently spontaneously resolved. No definitive growth disturbance was noticed. At 27 months mean follow-up, a best subjective IKDC score was found in group 1. Objective IKDC and radiological results were similar in both groups. Early ACL reconstruction is therefore a recommended option.

Anterior cruciate ligament reconstruction in the skeletally immature: an anatomical study utilizing 3-dimensional magnetic resonance imaging reconstructions

INTRODUCTION

Anatomic anterior cruciate ligament (ACL) reconstruction has proven to be a reliable method to restore knee stability. However, the risk of physeal arrest with transphyseal tunnel placement in skeletally immature patients has raised concern regarding this technique. Conservative nonoperative management also has its limitations resulting in meniscal and chondral damage that may lead to degenerative joint disease and poor return to sport. Researchers have used animal models to study the threshold of physeal damage producing growth deformity. The purpose of this study was to examine the distal femoral and proximal tibial physes and determine the damage produced by drilling transphyseal tunnels. In addition, we attempted to find a reproducible angle at which to drill the tibial tunnel for safe interference screw placement. To do this, we used a custom software module.

METHODS

A custom software package designed by our team was used: Module for Adolescent ACL Reconstructive Surgery (MAARS). This module created a 3-dimensional model of the distal femur and proximal tibia. The data required for MAARS were sagittal and coronal T1 magnetic resonance imagings of at least 1.5 T. Thirty-one knee magnetic resonance imaging studies from patients aged 10 to 15 years old were used. The physes were segmented out to obtain volumetric measurements. Transphyseal tunnels were simulated based on the anatomic trajectory of the native ACL. The module calculated volume of physis was removed with the use of an 8-mm tunnel and the optimum angle for trajectory.

RESULTS

Average volume of the tibial and femoral physis was 12,683.1 microL and 14,708.3 microL, respectively. The volume increased linearly with age. Average volume removed from the tibial and femoral physis was 318.4 microL and 306.29 microL, respectively. This represented 2.4% of the distal femoral physis and 2.5% of the proximal tibial physis. The volume percent removed decreased linearly with age.Manipulation of the variables demonstrates graft radius is the most critical parameter affecting the volume of physeal injury. Variation of graft diameter from 6 mm to 11 mm will increase volume percent removed from 2.3% to 7.8%, which averages 1.1% for every 1 mm increase. Increasing tunnel drill angle from 45 degrees to 70 degrees will decrease volume percent removed from 4.1% to 3.1% which averages 0.2% removed for each 5 degrees increase in drill angle. The average angle to maintain a distance of 20 mm from the proximal tibial physis was 65 degrees with a range of 40 degrees to 85 degrees.

DISCUSSION

Less than 3% injury occurs when drilling an 8-mm tunnel across the physis. A vertical tunnel has minimal effect, but the tunnel diameter is critical. Interference screws can be placed safely to avoid the physis but requires careful planning. The MAARS module may be helpful in preoperative planning.

LEVEL OF EVIDENCE

Diagnostic, level IV.

Hindlimb growth after a transphyseal reconstruction of the anterior cruciate ligament: a study in skeletally immature sheep with wide-open physes

BACKGROUND

There is a lot of controversy in the recent literature with regard to the optimal treatment of anterior cruciate ligament (ACL) injuries during growth. Iatrogenic growth disturbance due to physeal damage is a potential complication, forcing many orthopaedic surgeons to treat these injuries conservatively.

HYPOTHESIS

It is possible to perform a fully transphyseal ACL reconstruction in an ovine model with wide-open physes without creating growth disturbances.

STUDY DESIGN

Descriptive laboratory study.

MATERIALS AND METHODS

Four-month-old skeletally immature sheep underwent a transphyseal ACL reconstruction of the right knee. The surgical technique followed the criteria known to be essential to avoid growth disturbances in humans; the tibial tuberosity was spared to prevent a genu recurvatum, thermal damage to the growth plates was avoided, the physes were perforated with a small-diameter drill in the center of the growth plate, a soft tissue graft was used, graft fixation was achieved far away from the growth plates, the perforated growth plates were filled by the soft tissue graft, and the graft was moderately pretensioned before fixation. The left knee served as a control. A computer-assisted evaluation of long radiographs (frontal and sagittal plane) of the exarticulated hindlimbs was performed to exactly evaluate the limb alignment, joint orientation, and leg length. The animals were sacrificed in groups of 6 after 3, 6, 12, and 24 weeks.

RESULTS

No angular deformities or leg-length discrepancies occurred after this transphyseal ACL reconstruction procedure throughout the remaining growth.

CONCLUSION

This large-animal study supports the clinical observation that it is possible to perform an ACL reconstruction without creating growth disturbances as long as a number of key principles are followed.

CLINICAL RELEVANCE

Previous animal studies argued against ACL reconstruction in skeletally immature patients. This large-animal study provides support for early operative treatment of ACL ruptures even in young patients with open physes.

Living related donor allograft for revision anterior cruciate ligament reconstruction in a child: a case report

Revision ACL reconstruction poses several challenges for the surgeon in terms of the timing of surgery and the limited graft choices. To our knowledge, there is currently no published data with regards to revision ACL reconstruction in a child. We describe the case of a 12-year-old girl who had a re-injury 4.5 months after her index primary ACL reconstruction at the age of 11 years. She sustained a repeat injury to the reconstructed knee following a road traffic accident and developed significant instability despite an intensive rehabilitation program. After careful consideration of the available graft materials--known all the advantages and disadvantages of the autografts, allografts and synthetic materials--we decided to use the patient's mother's hamstrings as a graft. The parents of our patient refused the use of allograft and synthetic materials. We discuss our management of this case, the reasons for our revision graft choice, and the theoretical disadvantages of some of the alternative graft choices available in this scenario. We believe in such cases, performing ACL revision with a donor graft of the patient's mother could be good alternative to allografts or synthetic grafts.