All-epiphyseal Anterior Cruciate Ligament Reconstruction Research Articles

Anterior Cruciate Ligament Reconstruction With Iliotibial Band Autograft in Skeletally Immature Prepubescent Children: A Physeal-Sparing Technique

Background: As there has been an increasing incidence of anterior cruciate ligament (ACL) tears in children and adolescents in the past few decades, nonoperative management is seen to result in less favorable clinical outcomes, resulting in meniscal and cartilage damage, and arthritic changes. Despite the risk of iatrogenic physeal injuries with operative approach, several reconstruction options, such as physeal-sparing techniques for skeletally immature patients, are described to restore joint stability. Indications: We bring a combined extra-articular and intra-articular ACL reconstruction technique using autogenous iliotibial band (ITB), which is indicated for prepubescent patients (Tanner stages 1 or 2) with open physes, significant growth potential (≤11 years for girls and ≤12 years for boys) and smaller knees, where an all-epiphyseal ACL reconstruction would lack epiphyseal space Technique Description: The technique consists of a modified MacIntosh intra-articular and extra-articular ITB reconstruction, described by Micheli and further characterized by Kocher. The central portion of the ITB is harvested proximally (at least 15 cm) and left attached to Gerdy's tubercle distally. The harvested graft is brought from over-the-top posteriorly and passed under the intermeniscal ligament anteriorly through an epiphyseal groove on the tibia. Results: The outcomes shown for the Kocher ITB ACL reconstruction technique are favorable at a mean follow-up of 5.3 years: from 44 patients, 41 returned to sports involving cutting or pivoting, and the revision rate was low at 4.5%. Discussion/Conclusion: The awareness of physeal injury related to the operative treatment of ACL tears in the pediatric population has resulted in several physeal-sparing and physeal-respecting techniques of reconstruction. Some of these have shown to reduce the risk of physeal damage, maintaining stability and providing excellent functional outcomes, with low revision rates in long-term follow-up and minimal risk of growth disturbance. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Anterolateral and Direct Lateral Tunnel: Two Safe Zones for Femoral Drilling During All-Epiphyseal Anterior Cruciate Ligament Reconstruction – A Digital Three-Dimensional MRI Simulation Model Study

Anterolateral and Direct Lateral Tunnel: Two Safe Zones for Femoral Drilling During All-Epiphyseal Anterior Cruciate Ligament Reconstruction – A Digital Three-Dimensional MRI Simulation Model Study

Anterior Cruciate Ligament Reconstruction in Skeletally Immature Athletes Using All-Epiphyseal Techniques.

All-epiphyseal anterior cruciate ligament reconstruction (AE ACLR) has become an alternative technique for skeletally immature patients with a significant amount of growth remaining. This technique involves graft fixation within the epiphysis without crossing the physis. Either quadriceps tendon or hamstring autograft can be used when performing this procedure. Previous studies have shown that the complication rate is not higher in AE techniques versus previously developed techniques. Additionally, in our hands, the revision rate was found to be significantly lower in an AE ACLR compared with patients who had a transphyseal ACLR.

Techniques in Pediatric Anterior Cruciate Ligament Reconstruction

In recent years, the frequency of anterior cruciate ligament (ACL) tears and ACL reconstruction (ACLR) in skeletally immature patients has increased. Because distal femoral and proximal tibial physes account for the majority of lower-extremity growth, surgical technique and graft selection are crucial to minimize iatrogenic physeal injury. Combined extra- and intra-articular, all-epiphyseal, and transphyseal with soft-tissue grafts are the most common ACLR techniques used in children. Combined extra- and intra-articular ACLR typically is offered to prepubescent patients with ≥2 years of growth remaining. This technique uses iliotibial band (ITB) autograft passed over the lateral femoral condyle and fixed to the anterior tibial periosteum. All-epiphyseal ACLR is similarly used in patients with ≥2 years of growth remaining, provided sufficient epiphyseal maturity to accommodate an all-epiphyseal socket because both the femoral and tibial tunnels are contained within the epiphyses. In postpubertal patients with <2 years of growth remaining, transphyseal ACLR using a soft-tissue autograft (typically hamstring or quadriceps tendon) and metaphyseal femoral fixation can be performed. This minimizes risk of physeal injury. In borderline patients with approximately 2 years of growth remaining, an additional option includes partial transphyseal ACLR, which uses a soft-tissue graft and a transphyseal tibial tunnel, but an all-epiphyseal or over-the-top femoral graft trajectory. Recently, transphyseal ITB ACLR and hybrid transphyseal hamstring with combined over-the-top ITB ACLR also have been described. Existing clinical studies focused on pediatric and adolescent ACL reconstructions have reported a wide range of graft rupture rates for these techniques (4.3%-25%), with contralateral ACL injury rates of 2.9% to 15.6%. Ongoing multicenter research is underway to directly compare surgical techniques for this demographic and quantify graft rupture rates and other clinical outcomes.

Robot-assisted all-epiphyseal anterior cruciate ligament reconstruction in skeletally immature patients: a retrospective study.

To review a series of adolescent patients with anterior cruciate ligament (ACL) injuries surgically treated with robot-assisted all-epiphyseal ACL reconstruction (ACLR), and to compare with the traditional freehand group. This retrospective clinical study included 16 patients with ACL injuries who underwent ACLR by robot-assisted technique or traditional freehand method from June 2018 to March 2020. All patients were divided into the robot-assisted group (6 patients) or the traditional surgery group (10 patients). The number of intra-operative fluoroscopies, operation time, accuracy of bone tunnel insertions, International Knee Documentation Committee (IKDC) subjective score and ligament laxity testing were recorded in the two groups. All patients returned for follow-up, at a mean of 31.6 ± 4.5months after surgery. The average age of the robot-assisted group was 12.2 ± 1.3years. The number of intra-operative fluoroscopies was 10.9 ± 2.8 in the traditional freehand group, whereas it was only 3.0 ± 0.6 in the robot-assisted group, which was significantly lower (P < 0.05). The operative time in the robot-assisted group was shorter than that in the traditional freehand group (87 ± 10.7min vs. 126 ± 12.1min, P < 0.05). The distance between the center of actual insertion and the center of the idea insertion on both femoral and tibial intra-articular bone tunnel were 1.5 ± 0.3mm and 1.6 ± 0.3mm for the robot-assisted group and 2.7mm ± 0.4mm and 2.4 ± 0.4mm for the traditional freehand group (P < 0.05). There were no significant differences between the two groups in function recovery at the last follow-up. All-epiphyseal ACLR is a technically demanding procedure with a small margin of error. Robot-assisted treatment of ACL injuries in skeletally immature patients is more accurate than traditional freehand method, with shorter operation time and fewer intra-operative fluoroscopies.

Poster 229: Improved Epiphyseal Socket Placement with Intraoperative 3D Fluoroscopy: Consecutive Series of Pediatric All-epiphyseal Anterior Cruciate Ligament Reconstruction.

Objectives:All-epiphyseal anterior cruciate ligament reconstruction (ACLR) is a safe procedure for skeletally immature patients with ACL tears because the sockets are contained within the epiphysis and do not cross the growth plate. However, due to the undulation of the distal femoral physis, accidental disturbance of the growth plate during tunnel placement is possible. It is imperative to obtain intraoperative imaging to view the trajectory of the guide wire prior to reaming the socket. The purpose of this study was to investigate the effect of the use of 3D intraoperative fluoroscopy on socket placement in patients undergoing all-epiphyseal ACLR. We hypothesized that 3D imaging would allow for better intraoperative visualization of the growth plate and a smaller incidence of growth plate violation.Methods:Patients under the age of 18 who underwent a primary ACLR between 2011 and 2018 by the senior authors were retrospectively reviewed. Patients that underwent an all-epiphyseal ACLR with an available postoperative MRI were included. Demographic data, surgical details and type of intraoperative fluoroscopy were collected. The minimal distances between the femoral socket and distal femoral physis (DFP) and tibial socket and proximal tibial physis (PTP) were recorded. Sockets that touched the physis or extended into the metaphysis were recorded as zero. Patients were split into two groups; a 2D imaging group that received intraoperative anterior to posterior and lateral fluoroscopic radiographs and a 3D fluoroscopy imaging group. Interrater reliability of radiographic measurements was evaluated using intraclass correlation coefficient (ICC). Statistical analysis was performed using a student’s t-test to determine differences between groups.Results:72 patients fit the inclusion criteria and were retrospectively reviewed. 54 patients had 2D imaging and 18 patients had 3D imaging. The mean age of the cohort at time of surgery was 12.3 ± 1.5 years, 79% of patients were male, and 54% tore their left ACL. The mean time from surgery to postoperative MRI was 2.0 ± 1.1 years. The ICC was 0.92 (95% CI 0.35-0.98), indicating almost perfect interrater reliability. The mean difference in distance between the tibial socket and the PTP was significantly less in the 2D imaging group than the 3D imaging group (1.2 ± 1.7mm vs 2.5 ± 2.2mm, p=0.03). (Table 1). The femoral socket touched or extended beyond the DFP significantly less in the 2D group than in the 3D group (13% vs 43%, p<0.000).Conclusions:There was a significantly decreased incidence of DFP violation with use of 3D intraoperative imaging for all-epiphyseal ACLR socket placement. Surgeons should consider utilizing 3D imaging to potentially decrease the rate of growth disturbance due to physis violation in these patients.

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

Disturbance of the growth plate during all-epiphyseal anterior cruciate ligament reconstruction (ACLR) socket placement is possible due to the undulation of the distal femoral physis and proximal tibial physis. Therefore, it is important to obtain intraoperative imaging of the guide wire prior to reaming the socket. The purpose of this study was to investigate the effect of the use of 3D intraoperative fluoroscopy on socket placement in patients undergoing all-epiphyseal ACLR. It was hypothesized that 3D imaging would allow for more accurate intraoperative visualization of the growth plate and hence a lower incidence of growth plate violation compared to 2D imaging. Patients under the age of 18 who underwent a primary all-epiphyseal ACL reconstruction by the senior authors and had an available postoperative MRI were retrospectively reviewed. Demographic data, surgical details, and the distances between the femoral socket and distal femoral physis (DFP) and tibial socket and proximal tibial physis (PTP) were recorded. Patients were split into two groups based on type of intraoperative fluoroscopy used: a 2D group and a 3D group. Interrater reliability of radiographic measurements was evaluated using intraclass correlation coefficient (ICC). Seventy-two patients fit the inclusion criteria and were retrospectively reviewed. 54 patients had 2D imaging and 18 patients had 3D imaging. The mean age at time of surgery was 12.3 ± 1.5years, 79% of patients were male, and 54% tore their left ACL. The mean time from surgery to postoperative MRI was 2.0 ± 1.1years. The ICC was 0.92 (95% CI 0.35-0.98), indicating almost perfect interrater reliability. The mean difference in distance between the tibial socket and the PTP was significantly less in the 2D imaging group than the 3D imaging group (1.2 ± 1.7mm vs 2.5 ± 2.2mm, p = 0.03). The femoral and tibial sockets touched or extended beyond the DFP or PTP, respectively, significantly less in the 3D group than in the 2D group (11% vs 43%, p < 0.000, 17% vs 65%, p < 0.000). There was a significantly increased distance from the PTP and decreased incidence of DFP violation with use of 3D intraoperative imaging for all-epiphyseal ACLR socket placement. Surgeons should consider utilizing 3D imaging prior to creating femoral and tibial sockets to potentially decrease the risk of physis violation in these patients. III.

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.

Transepicondylar Distance Can Predict Graft and Tunnel Length for Different Pediatric Anterior Cruciate Ligament Reconstruction Techniques: A Magnetic Resonance Imaging Study

To find a correlation and mathematical formulas between a linear 2-dimensional (2D) magnetic resonance imaging (MRI) measurement around the knee and the length of the grafts and tunnels required for both all-inside-all-epiphyseal and Kocher-Micheli pediatric anterior cruciate ligament (ACL) reconstruction techniques. At time 0 and 30 days after, 2 observers measured: (1) on standard 2D knee MRI, 7 linear distances, representing morphologic measurements, such as transepicondylar distance (TD), and (2) on 3-dimensional (3D) MRI, 5 curved distances, corresponding to Kocher-Micheli and all-epiphyseal ACL reconstruction techniques. Intra- and interobserver reliability was tested for all measurements. The correlation between 2D and 3D measurements was tested. The 2D measurement with highest repeatability and reproducibility and with strongest correlation with 3D measurements was used to extract formulas to calculate the tunnel and graft length for the 2 techniques. Seventy-six MRIs were used. The intra- and interobserver reliability of 2D measurement was high, with TD showing the highest reproducibility and repeatability. 3D measurements also showed good intra and inter-observer reliability. A linear correlation was found between 2D and 3D measurements, with TD showing the strongest correlation. TD was used to extract formulas to calculate graft or tunnel length for Kocher-Micheli and all-epiphyseal ACL reconstruction. All formulas were proven to be accurate. A reference chart was also created to be used in the surgical setting. With specific formulas, TD can be used to calculate the length of the tunnels, intra-articular portion and graft length for an all-inside all-epiphyseal pediatric ACL reconstruction and the length of the iliotibial band required for the Kocher-Micheli technique. The surgeon can use these formulas in pediatric ACL reconstruction preoperative planning, graft harvesting and tunnel drilling.

Anatomic all-epiphyseal ACL reconstruction with "inside-out" femoral tunnel placement in immature patients yields high return to sport rates and functional outcome scores a minimum of 24months after reconstruction.

To understand if anatomic physeal-sparing ACL reconstruction in the immature host preserves range of motion, permits a return to sports, and avoids limb length discrepancy and accelerated intra-articular degeneration with a cross-sectional radiographic, physical examination and patient-reported outcomes analysis. A cross-sectional recall study included 38 patients aged 7-15 who underwent all-epiphyseal ACL reconstruction with hamstring allograft performed by a single surgeon at a large academic medical center. All-epiphyseal reconstructions were performed using a modified Anderson physeal-sparing technique, with the femoral tunnel placed using an "inside-out" technique. Assessments consisted of a physical exam, long leg cassette radiographs, KT-1000 measurements, subjective patient metrics, and magnetic resonance imaging. Thirty-eight (56.7%) of 66 eligible patients returned for in-person clinical and radiographic exams. Patients were 11.4 ± 1.8years at the time of surgery. Five patients were females (13.2%). Mean follow-up was 5.5 ± 2.4years. ACL re-injuries occurred in four patients (10.5%), all of whom underwent revision reconstructions. Thirty-three of the remaining 34 (97.1%) patients returned to sports following their reconstruction, and 24 (70.6%) returned to their baseline level of competition. Mean limb length discrepancy (LLD) was 0.2 ± 1.4cm. Nine patients had an LLD of > 1cm (26.5%), which occurred at an equivalent age as those with < 1cm LLD (10.8 ± 2.0 vs. 11.7 ± 1.7, n.s.). Pre-operative Marx scores (13.1 ± 3.5) were not significantly different from post-operative values (12.3 ± 5.1, n.s.). Patients who required ACL revisions had significantly lower Marx scores than those with intact primary grafts (8.3 ± 7.1 vs. 13.4 ± 4.5, p = 0.047). Cohort mean International Knee Documentation Committee (IKDC) score was 89.7 ± 12.7. Anatomic all-epiphyseal anatomic ACL reconstruction appears to be useful in patients with significant projected remaining growth, with good return-to-sport outcomes and minimal risk of clinically significant physeal complications. However, given the limited patient recall possible in the present study, further large sample size, high-quality works are necessary to validate our findings. Level IV.

All-Epiphyseal Double-Bundle Anterior Cruciate Ligament Reconstruction for Skeletally Immature Patients

The number of anterior cruciate ligament (ACL) reconstructions in skeletally immature patients has been gradually increasing in recent years owing to the poor outcomes of conservative treatment. However, ACL reconstruction in children is a challenging procedure and may lead to severe complications, such as growth disturbance. Although double-bundle (DB) ACL reconstructions are preferable because of their superior clinical outcomes, there are few reports of DB ACL reconstruction in children with open epiphyses. In this Technical Note, an all-epiphyseal sparing DB ACL reconstruction technique, which is considered to help avoid growth disturbance, is described. This procedure does not create a thick tunnel and may facilitate subsequent revision surgery.

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

To assess the literature on indications, outcomes, and complications in pediatric patients undergoing all-epiphyseal (AE) anterior cruciate ligament reconstruction (ACLR). PubMed, Medline, and Embase were searched for literature evaluating AE ACLR in pediatric patients. All included studies were assessed for quality using the Methodological Index for Non-Randomized Studies (MINORS). Descriptive statistics are presented where applicable. Overall, 17 studies comprising 545 patients, with a mean age of 12.0 ± 1.2 (range 8-19) met the inclusion criteria. The graft choices in this systematic review included hamstring tendon autografts (75.4%, n = 403), quadriceps tendon autograft (6.2%, n = 33), Achilles tendon allograft (3.6%, n = 19) and posterior tibialis tendon allograft in one patient (0.2%, n = 1). Time of return-to-sport ranged from 8 to 22months. Postoperative subjective IKDC scores were above 90 points. The rate of return-to-sport after AE ACLR was 93.2% (n = 219/235) and 77.9% (n = 142/183) of patients returned to sport at pre-injury level. The overall complication rate was 9.8% (n = 53/545) with the most common complication being ACL re-rupture (5.0%; n = 27/545). Only 1.5% (n = 8/545) of patients demonstrated growth disturbances. Overall, the AE ACLR technique can achieve good postoperative functional outcomes while notably minimizing the incidence of primary issue of physeal disruption and potential associated leg-length discrepancies. AE ACLR should be considered in pediatric patients with at least 2years of skeletal growth remaining based on radiographic bone age to minimize the impact of growth-related complications. IV (Systematic Review of Level III and IV evidence).

ACL GROWTH WITH AGE IN PEDIATRIC PATIENTS: AN MRI STUDY

BackgroundThe incidence of anterior cruciate ligament (ACL) injury is steadily increasing in skeletally immature patients [1-7]. As a result, surgical approaches to reconstruction of the ACL withou...

PEDIATRIC ACL RECONSTRUCTION: DOES THE FEMORAL PEEK IMPLANT CAUSE TUNNEL WIDENING?

Background: Because of their strength, inertness and biocompatibility, polyetherketone (PEEK) implants have been increasingly used in orthopedics, especially trauma and spine surgeries. Their mechanical and chemical properties have been widely studied and compared to other materials since their accelerated development in the 1980s. Their use is relatively new in anterior cruciate ligament reconstructions (ACLR), and there is little literature to document their effect on tunnel widening in these procedures. Bone tunnel enlargement following ACLR is a widely reported phenomenon that has been negatively correlated with clinical outcome scores. A recent prospective study reiterated its stronger association with suture discs compared with methods using interference screws, cross-pins and buttons. There is only one paper that specifically reports the results of a study on PEEK implants in relation with tunnel widening and it did not demonstrate significant association. PEEK polymer has not yet been studied in pediatric knees, in which tunnel widening has more than the usual residual laxity and re-tear implications, as it can also cause physeal damage. The purpose of this study was to investigate the use of a femoral PEEK implant in ACLR performed on skeletally immature patients and to determine if it is associated with tunnel widening. As a secondary objective, this study aimed to assess the risk of growth complications associated with the use of PEEK. Methods: All patients who underwent all-epiphyseal ACLR surgery in a pediatric university hospital between March 2015 and January 2017 were included in this retrospective study. The all-epiphyseal ACL reconstruction procedures were done using a new instrumentation system that includes a titanium tibial anchor fixation and a femoral PEEK screw system. Femoral bone tunnel diameters were measured on postoperative lateral knee radiographs. The widest tunnel measurements were taken using the sclerotic tunnel margins as reference points and compared to the known sizes of the drill bits retrieved from operative protocols. Paired t tests were performed to assess bone tunnel widening. P-values &lt;0.05 were considered significant. SPSS 25.0 was used for statistical analysis. Results: Eighteen (19 knees) arthroscopic ACL reconstruction patients were included. Of the 18 all-epiphyseal ACL reconstruction patients, 4 (22.2%) were female and 14 (77.8%) were male. The chronological and bone ages at time of surgery (mean ± SD) were respectively 13.5 ± 1.6 and 13.3 ± 1.0 years. At a mean follow-up of 17.1 months, average tunnel enlargement was 1.8± 1.4 (0.0-4.2) mm at the femur and was found to be statistically significant (P&lt;0.001). There were no symptomatic growth abnormalities requiring intervention, but 2 unilateral early physeal closures at the distal femur (10.5%) were noted. These patients had notable femoral tunnel enlargement. One had a 3.0 mm of femoral tunnel widening and no observable growth disturbance. The other had an asymptomatic and non-progressive unilateral knee valgum of 5 degrees and 3.5 mm of femoral tunnel widening. Conclusions/significance: This study showed that the largest tunnel increase at a mean follow up of 17.1 months was 4.2 mm. It is not clear that this widening is clinically significant even though it is statistically significant. Also, association between femoral tunnel widening and physeal closure could not be formally established. Thus, further research on this potential risk factor is needed.

Comparing Outcomes Between the Over-the-Top and All-Epiphyseal Techniques for Physeal-Sparing ACL Reconstruction: A Narrative Review.

A variety of techniques are used for physeal-sparing anterior cruciate ligament (ACL) reconstruction; however, there is no clear consensus on the ideal surgical technique, the frequency of complications, and how to best avoid growth disturbance. The purpose of this study was to compare outcomes and complications between over-the-top and all-epiphyseal ACL reconstruction techniques. The hypothesis was that both physeal-sparing reconstruction techniques are efficacious, with similar risk of growth disturbance and complications. The Embase and PubMed databases were queried for studies on ACL ruptures in the skeletally immature population from 1985 to 2018. Full-text English studies were included (N = 160). Studies reporting rerupture and/or complications after physeal-sparing ACL reconstruction, specifically growth disturbance, were included (n = 10). Studies were separated into 2 groups: an all-epiphyseal group with femoral and tibial fixation points within the epiphysis and a group that had over-the-top femoral and tibial physeal-sparing reconstruction. Complications not specific to the pediatric population were excluded. Demographics, evaluation of skeletal maturity, surgical technique, growth disturbance, rerupture, and patient-reported outcome scores were collected. Data were analyzed in aggregate. The 10 studies included 482 knees. The mean age was 12.0 years; 81% of patients were male; and mean follow-up was 47.7 months. A total of 178 patients underwent all-epiphyseal reconstruction, and 298 had the femoral graft placed over the top. The rerupture rate was 9.0% (16 of 178) in the all-epiphyseal group and 7.2% (14 of 195) in the over-the-top group, of which 82% required revision reconstruction. Six patients had overgrowth in the all-epiphyseal group (mean, 1.8 cm) and 1 patient in the over-the-top group (1.5 cm). Three angular deformities occurred, all of which were in the over-the-top group. Both physeal-sparing ACL reconstruction techniques are successful. Overgrowth was more common in the all-epiphyseal group and angular deformity in the over-the-top group. Rerupture rates were similar between the groups. The authors recommend standardization of skeletal age assessment and baseline lower extremity alignment films.

OVER-THE-TOP VERSUS ALL-EPIPHYSEAL TECHNIQUE FOR PHYSEAL SPARING ACL RECONSTRUCTION

BACKGROUND A variety of techniques are utilized for physeal sparing ACL reconstruction, however, no clear consensus exists on the ideal surgical technique, the frequency of complications, and how to best avoid growth disturbance. The purpose of this systematic review is to compare outcomes and complications between over-the-top and all-epiphyseal ACL reconstruction techniques. METHODS The EMBASE and PubMed databases were queried for studies on ACL ruptures in the skeletally immature from 1985 to 2016. Full-text, English studies discussing operative intervention on skeletally immature patients with ACL tears were included (n = 160). Studies that reported re-rupture and/or complications after physeal sparing ACL reconstruction, specifically growth disturbance, were then included in a secondary analysis (n=10). Studies were separated into two groups: an all-epiphyseal group with femur and tibia fixation points within the epiphysis and a group that had over-the-top femur and tibia physeal-sparing reconstruction. Complications that were not specific to the pediatric population were excluded. Angular deformity greater than 3 degrees between the operative and non-operative extremities was used as the threshold. Patient demographics, evaluation of skeletal maturity and growth disturbance, graft type, surgical technique, follow up, growth disturbance, re-rupture, and patient reported outcome scores were collected. Data was analyzed in aggregate. RESULTS Ten studies were included with 280 knees in 279 patients. The average age was 11.8 years, 79% were male, and the mean post-operative follow up was 46.2 months. There were 178 patients who underwent all-epiphyseal reconstruction and 102 patients who underwent ACL reconstruction with the femoral graft placed in an over-the-top position. The overall re-rupture rate was 8.2% (23 of 280). There were 16 re-ruptures in the all-epiphyseal group (9%), and 7 re-ruptures in the over-the-top group (6.9%). Of those studies that specified treatment for re-rupture, 80% of patients required revision ACL reconstruction. Two studies did not conduct objective assessment of skeletal maturity. The majority of studies (50%) did not assess for baseline limb length inequality or angular deformity. 30% of studies performed routine hips-to-ankles bilateral lower extremity radiographs. 20% of studies assessed baseline LLD/angular deformity using clinical examination. Post-operatively, 50% of studies obtained routine hips-to-ankles lower extremity radiographs. 30% of studies obtained post-operative alignment imaging only if there was clinical suspicion of growth disturbance. There were ten total growth disturbances (3 required corrective surgery, or 30%). Seven knees developed limb overgrowth (six in the all-epiphyseal group (mean 1.8 cm) and one in the over-the-top group, 1.5 cm). Two of the patients with overgrowth from the all epiphyseal group required epiphysiodesis (28.6%). Five patients were observed. There were two angular deformities (one with 4 degrees of valgus, and another with 4 degrees varus), both in the over-the-top group which were treated with observation. There were no knees which developed angular deformity in the all epiphyseal group. One patient from the over-the-top group developed a multi-planar flexion-valgus deformity and required distal femoral osteotomy for correction. Five studies reported excellent Lysholm scores of 96.4. Six studies reported IKDC scores (range 88.5-100, 93% grade A or B). CONCLUSIONS / SIGNIFICANCE Growth disturbance after physeal sparing ACL reconstruction was overall uncommon and mild. The phenomenon of overgrowth was common likely due to younger patients receiving physeal sparing procedures. Overgrowth was more common in the all-epiphyseal group and angular deformity in the over-the-top group. Re-rupture rates were similar between the two groups. Evaluation of pre-operative skeletal maturity and comparison of baseline to post-operative growth disturbance was limited by lack of routine imaging assessment. We recommend routine PA hand radiographs, and pre- and post-operative hips-to-ankles alignment radiographs in all skeletally immature patients prior to undergoing ACL reconstruction. Further multi-center study with patient reported outcomes and long-term follow-up are necessary to determine the ideal reconstructive technique in the young, skeletally immature population.

Validated Pediatric Functional Outcomes of All-epiphyseal ACL Reconstructions: Does Reinjury Affect Outcomes?

Greater frequency and intensity level of sports participation may be contributing to an increasing incidence of anterior cruciate ligament (ACL) tears in skeletally immature athletes. Prior studies have assessed the functional outcomes of physeal-respecting ACL reconstruction in this patient population based on adult functional outcomes scoring systems; however, there is only sparse literature evaluating functional outcomes of this specific patient population. This study aimed to retrospectively evaluate a cohort of pediatric patients who had undergone all-epiphyseal ACL reconstruction (AEACLR) with a set of clinically validated, pediatric-specific patient-reported functional outcomes scores (PRFOS). We hypothesized that patients who had rerupture would have significantly lower outcomes scores compared with those who did not rerupture. This was a retrospective evaluation of AEACLR patients at a single, tertiary care, children's hospital within a period of 2 years and had >6 months of initial clinical postoperative follow-up. Those who consented to participation were provided an online combined survey including questions relating to demographics and rerupture as well as 3 validated pediatric PRFOS. Statistical analysis of the cohort demographics, PRFOS, and subgroup analysis of the rerupture group compared with the ACL intact patients was performed. The mean functional outcome scores at a mean of 48.6 months from surgery demonstrated excellent return to functional activity (Mean International Knee Documentation Committee, 93.8; Pedi-Patient-Reported Outcomes Measurement Information System, 98.8; Pedi- Functional Activity Brief Score, 21.6). There was a 13% rerupture rate and rerupture patients had a significantly decreased Pedi-International Knee Documentation Committee (94.9 intact vs. 86.0 rerupture; P=0.001) and Pedi-Patient-Reported Outcomes Measurement Information System (99.4 intact vs. 95.4 rupture; P=0.001) scores. AEACLR patients have excellent outcomes based on pediatric-specific PRFOS. Rerupture patients demonstrated a decrease in functional outcomes scores compared with intact ACL patients. The results demonstrate the efficacy of AEACLR as measured by pediatric-specific functional outcome scores for the treatment of ACL rupture in skeletally immature athletes. Level III-retrospective comparative study.

Anterior cruciate ligament reconstruction with an all-epiphyseal "over-the-top" technique is safe and shows low rate of failure in skeletally immature athletes.

The aim of this study was to follow up, clinically and radiographically, skeletally immature patients who underwent ACL reconstruction with an all-epiphyseal "over-the-top" technique. Twenty athletes aged between 8 and 13 years were enrolled and retrospectively evaluated. The subjects underwent surgical ACL reconstruction between 2009 and 2013. The surgical technique consisted of a single-bundle all-epiphyseal ACL reconstruction with an extra-articular lateral tenodesis. The mean follow-up was 54months [34-123] after surgery. Clinically, the patients were evaluated pre- and post-operatively with Lysholm and KOOS scores; sport activity level was evaluated using the pre-injury, pre-operative and post-operative Tegner scores. Objective IKDC was calculated post-operatively. The joint laxity was evaluated by KT1000 and Rolimeter arthrometers. Panoramic AP standing radiographs of the lower limbs and lateral knee radiographs were also taken at the follow-up to evaluate limb length discrepancies (LLD) and axial malalignment. Normally distributed parameters were presented as mean ± standard deviation, while the non-normally distributed parameters were presented as median [25° percentile, 75° percentile]. Clinical scores showed significant (P < 0.01) improvement: Lysholm and KOOS scores improved from 40 [22; 65] and 59 [42, 73], respectively, to 100 [95; 100] and 99 [97;100] after surgery. Tegner score improved from 2 [2; 2] pre-operatively to 7 [3; 9] at follow-up (P < 0.01). At follow-up, IKDC score was A for 19 patients and one who scored B. All patients returned to sport activity and had good stability at follow-up: the KT1000 showed a median side-to-side difference of 0.0mm [- 0.4; 1.0] for the standard force evaluation and 0.0mm [- 1.0; 0.8] for manual-maximum test. The Rolimeter showed median side-to-site difference of 0.0mm [- 1.0; 0.8]. Three minor leg length discrepancies and axial deviations were observed at the radiograph: one patient had 0.6cm lengthening and 4° of varus, one had 1cm lengthening, and one had 3° of varus (in comparison with the non-operated limb). No re-injury was observed. This study demonstrates that the modified all-epiphyseal single-bundle "over-the-top" technique is a viable and safe option for ACL reconstruction in pediatric subjects. These results support once more that not only ACL reconstruction is a safe procedure in skeletally immature patients, but also it is highly recommended for those who want to pursue an active and sportive life. Case series, IV.

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

Background:Multiple surgical approaches have been described for the management of anterior cruciate ligament (ACL) tears in skeletally immature patients.Purpose:To provide a detailed description of a modified all-epiphyseal ACL reconstruction and report early outcomes and complications with this new technique.Study Design:Case series; Level of evidence, 4.Methods:A retrospective review of all skeletally immature patients undergoing ACL reconstruction via a modified all-epiphyseal technique prior to July 2015 was performed. Skeletally immature male patients with a bone age of 8 to 15 years and female patients with a bone age of 8 to 12 years were selectively indicated for this procedure. The surgical technique involved an all-epiphyseal femoral tunnel drilled parallel and distal to the physis as well as an all-epiphyseal tibial tunnel. Both tunnels were placed in the anatomic footprint of the ACL. Tibial fixation was achieved first with a suspensory cortical fixation device followed by fixation on the femur with an interference screw.Results:During the study period, 30 patients with a mean bone age of 11.8 years underwent ACL reconstruction with this physeal-sparing technique; 26 patients (87%) achieved a minimum follow-up of 2 years. At final follow-up, the mean Lysholm score, Single Assessment Numeric Evaluation score, patient satisfaction, return-to-sport rate, and Tegner activity score were 93, 89, 9.2, 94%, and 7.6, respectively. Four graft failures (15%) and 3 (12%) contralateral ACL tears were identified. One patient was noted to have a 12-mm leg-length discrepancy at final follow-up, which required no additional treatment. No other leg-length discrepancies or angular deformities were identified.Conclusion:The modified all-epiphyseal ACL reconstruction technique achieved good functional outcomes, a high rate of return to sport, low failure rates, and low physeal injury rates at a mean follow-up of 3.2 years. Skeletally immature patients with an ACL tear requiring reconstruction pose a unique challenge for sports medicine clinicians. While several previous approaches have been described for this patient population, the proposed benefits of this new technique are that it is anatomic, it is physeal sparing, it uses osseous tunnels, and it provides good initial graft fixation strength.

Biomechanical Comparison of Epiphyseal Anterior Cruciate Ligament Fixation Using a Cortical Button Construct Versus an Interference Screw and Sheath Construct in Skeletally Immature Cadaveric Specimens.

Background:Anterior cruciate ligament (ACL) ruptures have become increasingly common in pediatric and adolescent athletes. While multiple methods exist, all-epiphyseal ACL reconstruction is a popular technique in the skeletally immature patient. Given the high rate of reruptures in this population and the increasing number of commercially available fixation devices, biomechanical testing is crucial to understand the performance of these devices in pediatric epiphyseal bone. To our knowledge, there has not been a biomechanical analysis of ACL fixation devices in skeletally immature bone.Purpose:To compare cortically based button fixation with interference screw and sheath fixation in skeletally immature femoral epiphyseal cadaveric bone. Our hypothesis was that there would be no difference in peak load to failure, stiffness, or cyclic displacement between these 2 fixation constructs.Study Design:Controlled laboratory study.Methods:Fresh-frozen matched-pair knees from 3 pediatric cadaveric specimens were obtained. A synthetic graft was fixed in an all-epiphyseal femoral tunnel. Both the lateral and medial condyles were utilized to increase the sample size. Specimens were randomized and assigned to receive either an interference screw and sheath construct designed for pediatric patients or an adjustable loop cortical button. Biomechanical testing was performed to obtain ultimate load to failure, stiffness, total displacement after 500 cycles, and the failure mode for each condyle.Results:Each medial and lateral condyle in 3 pairs of skeletally immature cadaveric knees (ages 7, 9, and 11 years) was utilized for testing. One specimen was excluded after it failed by having a transphyseal fracture. The median peak load to failure was 769.80 N (interquartile range [IQR], 628.50-930.41 N) for the screw and sheath group and 862.80 N (IQR, 692.34-872.65 N) for the button group (P = .893). The median displacement after 500 cycles for the screw and sheath group was 0.65 mm (IQR, 0.47-1.03 mm) and 1.13 mm (IQR, 0.96-1.25 mm) for the button group (P = .08). The median stiffness of the screw and sheath group was significantly higher than that of the button group (31.47 N/mm [IQR, 26.40-43.00 N/mm] vs 25.22 N/mm [IQR, 21.18-27.07 N/mm], respectively) (P = .043).Conclusion:When comparing femoral fixation with a screw and sheath construct developed for pediatric patients to an adjustable loop cortical button in skeletally immature bone, our results showed that fixation did not significantly differ with respect to cyclic displacement or peak load to failure. While the screw and sheath construct was significantly stiffer, its effect on clinical outcomes is not yet known.Clinical Relevance:With regard to femoral fixation, there is no significant biomechanical difference between the use of cortically based button fixation or interference screw and sheath fixation in pediatric epiphyseal cadaveric bone.