Paediatric proximal ACL tears managed with direct ACL repair is safe, effective and has excellent short-term outcomes

Editorial Commentary: Primary Repair of the Anterior Cruciate Ligament Shows Positive Midterm Outcomes When Properly Indicated

Anatomic anterior cruciate ligament (ACL) reconstruction is the gold standard treatment for ACL injury and has been shown to restore the 3-dimensional joint laxity. Recently, however, there is renewed interest in primary repair of the injured ACL in selected cases. Research shows that, in some cases, short- and midterm outcomes of ACL repair are favorable, albeit with greater failure rates than ACL reconstruction. No long-term outcomes are yet available, which could address whether repair reduces risk of osteoarthritis relative to reconstruction with a graft. Historically, primary repair showed poor outcomes, but for proximal and acute injuries with good vascularity, innovations such as suture anchors, dynamic intraligamentary stabilization, and suture tape augmentation show promise, particularly in paediatric patients. The old orthopaedic dogma that "ACL cannot heal" is not entirely correct.

Management of Anterior Cruciate Ligament Tears in Skeletally Immature Patients

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Arthroscopic repair of proximal anterior cruciate ligament tears in children and adolescents: A systematic review

Purpose

Anterior cruciate ligament repair techniques are of growing interest because they allow for minimally invasive surgery that avoids harvesting of the transplant, without risking growth deficiencies in young patients. The aim of this study is to summarize the published evidence about arthroscopic repair of anterior cruciate ligament proximal tears in skeletally immature patients.

Methods

In total, four studies were included and processed for data extraction after screening for eligibility for this systematic review: one retrospective cohort study and three retrospective case series. Altogether, the four studies included in this review included 61 skeletally immature patients with a mean age of 12.1 years diagnosed with proximal anterior cruciate ligament tear who underwent arthroscopic repair with preservation of the native ligament. The mean follow-up period was 2.8 years.

Results

The most relevant and objective outcome that we considered was re-rupture rate. One study reports a cumulative incidence of graft failure in the first 3 years after surgery of 48.8% while the others report a 0%, 0% and 21.5% re-rupture rate. No growth disturbances were reported in the included studies.

Conclusion

Despite growing interest surrounding anterior cruciate ligament repair techniques, the presence of limited quality studies in the literature means repair cannot be strongly supported at present. Some encouraging data regarding the absence of growth disturbance and functional outcomes does exist, but studies with larger samples are required.

Level of evidence

level IV.

Rate of Revision Surgery and Associated Risk Factors After Primary Arthroscopic ACL Repair With Additional Suture Augmentation

Background

Recent studies have suggested promising patient-reported outcomes after primary anterior cruciate ligament (ACL) repair with additional suture augmentation (SA).

Purpose

To evaluate the risk for revision surgery and identify patient- and injury-related risk factors after ACL repair with SA in a large patient cohort subject to strict patient selection.

Study Design

Case-control study; Level of evidence, 3.

Methods

Included were 86 patients (61 female; 93% follow-up rate) who underwent arthroscopic ACL repair with SA between January 2017 and March 2019 by a single surgeon and had a minimum follow-up of 24 months. Patients were selected for surgery with regard to time to surgery (preferably on the day of injury), tear pattern (limited to Sherman types 1 and 2), and tissue quality (intact synovial coverage). Postoperatively, the patients who needed revision surgery were identified and compared with patients who did not undergo revision surgery, using the Mann-Whitney U test for nonparametric analysis and the Student t test for parametric analysis. A Kaplan-Meier analysis was performed to investigate the survival rate of the ACL repair.

Results

A total of 9 patients (10%; median age, 48 years; interquartile range [IQR], 27-50 years) underwent revision surgery at 12 months postoperatively (IQR, 8-25 months). The median follow-up of patients without revision surgery was 35 months (IQR, 33-44 months). The revision-free survival rate was 97% (95% CI, 93%-100%) after 1 year, 93% (95% CI, 88%-98%) after 2 years, and 90% (95% CI, 83%-97%) after 4 years. Patient-related factors-such as sex (P = .98), age at surgery (P = .459), body mass index (P = .352), and preinjury level of sports (P = .53)-had no significant impact on the survival rate of the ACL repair. Injury-related factors-such as concomitant injuries of the medial (P = .860) and lateral menisci (P = .414) and the medial (P = .801) and lateral collateral ligaments (P = .534) or same-day surgery compared with a delay of surgery of up to 18 days (P = .277)-had no significant impact on the survival rate of the ACL repair.

Conclusion

The revision rate of primary ACL repair with SA at a 2-year follow-up was 10%. Patient- and injury-related factors were not associated with the survival rate of the ACL repair.

Outcomes of Primary Anterior Cruciate Ligament (ACL) Repair for Proximal Tears: A Systematic Review and Meta-Analysis

The purpose of this study is to compare failure rates among different techniques of primary anterior cruciate ligament (ACL) repair for the treatment of proximal ACL ruptures. Meta-analysis and systematic review were completed, and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Studies from Embase, Cochrane, and PubMed published between June 2011 and June 2022 reporting outcomes of primary ACL repair on proximal tears with a minimum two-year follow-up were included. Primary ACL repair was divided into dynamic, static, and non-augmented repair. The primary outcome was failure rates, and the secondary outcomes included patient-reported outcomes (PROs) and anterior tibial stability (ATT). Eighteen studies on primary ACL repair were included, with a total of 614 patients (ages ranging from 6 to 65, 60% male). Only two studies were level 1 randomized controlled clinical trials. The static repair had a failure rate of 33 out of 261 (12.6%), non-augmented was 17 out of 179 (9.4%), and dynamic repair was 31 out of 174 (17.8%); no statistically significant difference was found comparing the failure rates (p = 0.090). PROs using the International Knee Documentation Committee (IKDC) and Lysholm scores had weighted averages of 91.7 (95% confidence interval (CI): 89.6-93.8) and 94.7 (95% CI: 92.7-96.7), respectively. ATT had a weighted average of 1.668 mm (95% CI: 1.002-2.334). The primary findings of this paper include a 12.6% combined failure rate for primary proximal ACL repair with no significant difference in failure rate or PROs when accounting for the methodology of repair at a minimum two-year follow-up. It is important to note the lack of high-quality randomized controlled trials, the heterogeneity of included studies, and the lack of long-term data. Despite these limitations, the findings of the current analysis suggest that primary repair may be a useful treatment option for indicated candidates with proximal ACL ruptures. Further long-term and higher-quality comparative studies on ACL reconstruction are warranted.

Management of Pediatric Anterior Cruciate Ligament Injuries: A Critical Analysis

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

Comparison of Primary Repair of the Anterior Cruciate Ligament and Anterolateral Structures to Reconstruction and Lateral Extra-articular Tenodesis at 2-Year Follow-up

BACKGROUND

Lateral extra-articular procedures have been effective in reducing graft rupture rates after anterior cruciate ligament (ACL) reconstruction (ACLR), but the evidence supporting their role in ACL repair is sparse.

PURPOSE/HYPOTHESIS

The purpose was to compare clinical and radiological outcomes of ACLR and lateral extra-articular tenodesis (LET) (ACLR+LET) against combined repair of the ACL and anterolateral (AL) structures (ACL+AL Repair). It was hypothesized that patients undergoing ACL+AL Repair would have noninferior clinical and radiological outcomes with respect to International Knee Documentation Committee (IKDC) scores, knee laxity parameters, and magnetic resonance imaging (MRI) characteristics. Furthermore, it was hypothesized that patients undergoing repair would have significantly better Forgotten Joint Score-12 (FJS-12) values and shorter times to return to the preinjury level of sport, without any increase in the rate of ipsilateral second ACL injury.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Consecutive patients evaluated with an acute ACL tear were considered for study eligibility. ACLR+LET was only performed when intraoperative tear characteristics contraindicated ACL repair. Patient-reported outcome measures such as the IKDC score, Lysholm score, and Knee injury and Osteoarthritis Outcome Score (KOOS); reinjury rates; anteroposterior side-to-side laxity difference; and MRI characteristics were reported at a minimum follow-up of 2 years. The noninferiority study was based on the IKDC subjective score; side-to-side anteroposterior laxity difference; and signal-to-noise quotient (SNQ). The noninferiority margins were defined using the existing literature. An a priori sample size calculation was performed using the IKDC subjective score as the primary outcome measure.

RESULTS

A total of 100 patients (47 ACLR+LET, 53 ACL+AL Repair) with a mean follow-up of 25.2 months (range, 24-31 months) were enrolled and underwent surgery within 15 days of injury. At the final follow-up, the differences between groups with respect to the IKDC score, anteroposterior side-to-side laxity difference, and SNQ did not exceed noninferiority thresholds. ACL+AL Repair was associated with a shorter time to return to the preinjury level of sport (ACL+AL Repair: mean, 6.4 months; ACLR+LET: mean, 9.5 months; P < .01), better FJS-12 values (ACL+AL Repair: mean, 91.4; ACLR+LET: mean, 97.4; P = .04), and a higher proportion of patients achieving the Patient Acceptable Symptom State (PASS) for the KOOS subdomains studied (Symptoms: 90.2% vs 67.4%, P = .005; Sport and Recreation: 94.1% vs 67.4%, P < .001; Quality of Life: 92.2% vs 73.9%, P = .01). There were no significant differences between groups with respect to ipsilateral second ACL injury rates (ACL+AL Repair group, 3.8% and ACLR+LET group, 2.1% [n = 1]; P = .63).

CONCLUSION

ACL+AL Repair yielded clinical outcomes that were noninferior to (or not significantly different from) ACLR+LET with respect to IKDC subjective, Tegner activity level, and Lysholm scores; knee laxity parameters; graft maturity; and rates of failure and reoperation. However, there were significant advantages of ACL+AL Repair, including a shorter duration of time to return to the preinjury level of sport, better FJS-12 values, and a higher proportion of patients achieving PASS for KOOS subdomains studied (Symptoms, Sport and Recreation, Quality of Life).

All-Epiphyseal Anterior Cruciate Ligament Repair Using Suture Ring Device in the Skeletally Immature Patient

Anterior cruciate ligament (ACL) tears in pediatric patients pose distinct challenges in management, especially in patients with open distal femoral and proximal tibial physes. There are a variety of contemporary reconstruction techniques that attempt to address these challenges. However, with the resurgence of ACL repair in the adult population, it has become apparent that the pediatric patient may also benefit from primary ACL repair rather than reconstruction. ACL repair is a procedure performed to treat ACL tears that avoids the donor-site morbidity seen with ACL reconstruction using autograft. We describe a surgical technique involving FiberRing sutures (Arthrex, Naples, FL) and TightRope-internal brace fixation (Arthrex) for ACL repair with all-epiphyseal fixation in the pediatric patient. The FiberRing is a knotless, tensionable suture device that can be used to stitch the torn ACL and coupled with the TightRope and internal brace to fix the ACL.

Augmenting ACL Repair With Suture Tape Improves Knee Laxity: A Biomechanical Study

Background

Anterior cruciate ligament (ACL) repair is an alternative to reconstruction; however, suture tape support may be necessary to achieve adequate outcomes.

Purposes

To investigate the influence of suture tape augmentation (STA) of proximal ACL repair on knee kinematics and to evaluate the effect of the 2 flexion angles of suture tape fixation.

Study Design

Controlled laboratory study.

Methods

Fourteen cadaveric knees were tested using a 6 degrees of freedom robotic testing system under anterior tibial (AT) load, simulated pivot-shift (PS) load, and internal rotation (IR) and external rotation loads. Kinematics and in situ tissue forces were evaluated. Knee states tested were (1) ACL intact, (2) ACL cut, (3) ACL repair with suture only, (4) ACL repair with STA fixed at 0° of knee flexion, and (5) ACL repair with STA fixed at 20° of knee flexion.

Results

ACL repair alone did not restore the intact ACL AT translation at 0°, 15°, 30°, or 60° of flexion. Adding suture tape to the repair significantly decreased AT translation at 0°, 15°, and 30° of knee flexion but not to the level of the intact ACL. With PS and IR loadings, only ACL repair with STA fixed at 20° of flexion was not significantly different from the intact state at all knee flexion angles. ACL suture repair had significantly lower in situ forces than the intact ACL with AT, PS, and IR loadings. With AT, PS, and IR loadings, adding suture tape significantly increased the in situ force in the repaired ACL at all knee flexion angles to become closer to that of the intact ACL state.

Conclusion

For complete proximal ACL tears, suture repair alone did not restore normal knee laxity or normal ACL in situ force. However, adding suture tape to augment the repair resulted in knee laxity closer to that of the intact ACL. STA with fixation at 20° of knee flexion was superior to fixation with the knee in full extension.

Clinical Relevance

The study findings suggest that ACL repair with STA fixed at 20° could be considered in the treatment of femoral sided ACL tears in the appropriate patient population.

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

Background

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

Methods

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

Results and Conclusions

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

Level of evidence

level IV.

Suture Augmentation in Orthopaedic Surgery Offers Improved Time-Zero Biomechanics and Promising Short-Term Clinical Outcomes

Ligament and tendon ruptures have historically been addressed with varying techniques involving either repair or reconstruction. More recently, the potential biomechanical benefits of suture augmentation (SA), also known as internal brace, have attracted substantial attention and helped renew interest in ligament repair surgery. We evaluated the biomechanical and clinical outcomes of SA-based techniques in the following sports medicine procedures: medial ulnar collateral ligament repair of the elbow, thumb collateral ligament repair, anterior cruciate ligament repair, Achilles' tendon repair, and deltoid ligament repair. Published data on the use of SA to augment repairs of the ulnar collateral ligament, thumb collateral ligament, anterior cruciate ligament, Achilles' tendon, and deltoid ligament repair demonstrates improved time-zero biomechanical and promising short to mid-term clinical outcomes. However, surgeons must be wary of potential complications, including joint over-constraint, nerve paresthesia, and infection.

Trends in Anterior Cruciate Ligament Repair: A Bibliometric and Visualized Analysis

Background:

Bibliometrics is a methodology that measures the scientific output of an author, institution, or country. Visualized analysis is the transformation of data into visible form by software, highlighting important features, including commonalities and anomalies, allowing users to easily and quickly perceive significant aspects of their data.

Purpose:

To conduct a bibliometric analysis of the literature on anterior cruciate ligament (ACL) repair, with visualization of trends, in order to identify the areas of interest and the primary researchers involved in ACL repair.

Study Design:

Cross-sectional study.

Methods:

The PubMed database was queried on April 14, 2022, for publications that reported on ACL repair from 1960 onward. The initial search resulted in 1392 publications. Filter settings were applied to remove publications with weak correlation, such as those on meniscal repair and ACL reconstruction. Publication information, citations, authors, commonly used terms, and affiliated institutions and countries were analyzed by VOSviewer and Python.

Results:

A total of 553 articles were included for analysis. Three techniques were visualized: bridge-enhanced ACL repair, internal brace, and dynamic intraligamentary stabilization. The most published authors were Martha Murray (51 articles), Gregory Difelice (35 articles), and Braden Fleming (31 articles). The most cited article was “Collagen–Platelet Rich Plasma Hydrogel Enhances Primary Repair of the Porcine Anterior Cruciate Ligament” by Murray et al. The journals with the most publications on ACL repair were the American Journal of Sports Medicine (n = 49); Knee Surgery, Sports Traumatology, Arthroscopy (n = 49); and Arthroscopy (n = 48). The top 3 institutions by publication number were the Hospital for Special Surgery (n = 51), Boston Children’s Hospital (n = 49), and Brown University (n = 31), with the most publications coming from the United States (n = 242), Germany (n = 83), and the United Kingdom (n = 47).

Conclusion:

The results demonstrate that the research on ACL repair comes from a small number of authors and corresponding institutions; the top sports medicine journals and the developed countries have an interest in this topic.

Primary repair with suture augmentation for proximal anterior cruciate ligament tears: A systematic review with meta-analysis

PURPOSE

To assess the outcomes of arthroscopic primary repair of proximal anterior cruciate ligament (ACL) tears with suture augmentation in the literature.

METHODS

A systematic search was performed using PubMed, EMBASE, and Cochrane for studies reporting on outcomes of primary repair of proximal ACL tears with suture augmentation between 2015 and 2021. Primary outcomes included failure and reoperation rates, whereas secondary outcomes consisted of functional outcomes. Proportion meta-analysis was performed to assess the overall incidence of failure rates. Outcomes of adults and adolescent were reported separately.

RESULTS

Thirteen studies with 418 patients were included in this study (mean age 32 years, mean follow-up 2.0 years, 49% male). There were no randomized studies and overall grade of recommendation was weak. Overall failure rate for primary repair with suture augmentation was 8% (95% CI 3.9-14.4), but this was higher for younger patients (17%; 95% CI 2.5-63.9) than for older patients (6%; 95% CI 3.8-8.9). The risk for additional reoperations, complications, or hardware removal was low (all <2%), while functional outcomes were good to excellent (all >80% of maximum score).

CONCLUSION

Current literature shows that primary repair with suture augmentation is a reliable treatment option for proximal ACL tears with a failure rate of 8% and good functional outcome scores at short-term follow-up. Although functional outcomes were good irrespective of age, failure rates were higher in young patients (17% vs 6%, respectively). There is a need for high-quality comparative studies with large group of patients to compare these outcomes with ACL reconstruction.

Paediatric injuries around the knee: Soft tissue injuries

We review the diagnosis, management and potential pitfalls of acute soft tissue injuries in the skeletally immature knee, including anterior cruciate ligament (ACL) injuries, meniscal injuries, patellar dislocation and patellofemoral instability (PFI). There has been an increasing incidence of such injuries in the paediatric population, and controversy remains regarding their treatment. We summarise evidence-based treatments for these injuries and discuss strategies to minimise complications as the child reaches skeletal maturity.

Current and future of anterior cruciate ligament reconstruction techniques

In recent years, anterior cruciate ligament (ACL) reconstruction has generally yielded favorable outcomes. However, ACL reconstruction has not provided satisfactory results in terms of the rate of returning to sports and prevention of osteoarthritis (OA) progression. In this paper, we outline current techniques for ACL reconstruction such as graft materials, double-bundle or single-bundle reconstruction, femoral tunnel drilling, all-inside technique, graft fixation, preservation of remnant, anterolateral ligament reconstruction, ACL repair, revision surgery, treatment for ACL injury with OA and problems, and discuss expected future trends. To enable many more orthopedic surgeons to achieve excellent ACL reconstruction outcomes with less invasive surgery, further studies aimed at improving surgical techniques are warranted. Further development of biological augmentation and robotic surgery technologies for ACL reconstruction is also required.

Skeletally immature patient showed lower graft maturity than skeletally mature patient after ACL reconstruction with a rounded rectangular femoral tunnel

To compare the clinical results and ligamentization of anterior cruciate ligament reconstruction (ACLR) between skeletally immature and mature patients. Two-hundred-and-two patients who underwent primary ACLR were evaluated retrospectively. The clinical outcomes were compared between skeletally immature (immature group 1, n = 27) and mature (control group 1, n = 175) groups. Graft ligamentization of the reconstructed anterior cruciate ligament (ACL) using magnetic resonance imaging (MRI) signal intensity at 6 months postoperatively was compared between immature group 2 (n = 16), which included participants from immature group 1, and control group 2 (n = 32), created by recruiting data-matched controls from control group 1. Immature group 1 had significantly higher revision (14.8%) and pivot shift test positive (22.2%) rates than control group 1 (2.9% and 4.0%, respectively) (P = 0.020 and 0.003, respectively). The signal intensity in immature group 2 were significantly higher at the mid-substance and distal site of the reconstructed ACL than those in control group 2 (P = 0.003 and 0.034, respectively). Skeletally immature patients had higher graft revision and residual rotational laxity rates. Reconstructed ACL in skeletally immature patients showed higher signal intensity on MRI at 6 months postoperatively.

Suture tape augmentation improves laxity of MCL repair in the ACL reconstructed knee

PURPOSE

Medial collateral ligament (MCL) injury is very common and surgical repair is sometimes necessary. Especially in the setting of simultaneous anterior cruciate ligament reconstruction (ACLR) as the ACL is the secondary restraint against valgus stress. The goal of this study was to evaluate knee biomechanics after suture repair of the MCL augmented with suture tape, as compared to MCL repair alone, in the setting of concomitant ACL reconstruction (ACLR).

METHODS

Fifteen fresh-frozen human cadaveric knees were tested using a six-degrees-of-freedom robotic system under four loadings: (a) an 89.0 N anterior tibial load, (b) a 5.0 Nm internal and external rotation torque, (c) a 10.0 Nm valgus load, (d) a 7.0 Nm valgus load combined with 5.0 Nm internal rotation torque as a static simulated pivot-shift. The tested conditions were ACLR with the following states: (1) MCL intact, (2) MCL deficient, (3) MCL Repair, and (4) MCL repair augmented with suture tape (MCL Repair + ST). Under the different knee loadings, the tibial displacement, and the force in either the intact MCL, suture repaired MCL or repaired MCL-suture tape complex was measured.

RESULTS

While neither the MCL Repair nor the MCL Repair + ST restored valgus rotation to the MCL intact state, displacement was significantly smaller after MCL Repair + ST (p < 0.05). The knee rotation under external rotation torque in MCL Repair + ST did not differ MCL intact (n.s.), while with MCL Repair the rotation was significantly greater (p < 0.05). MCL Repair + ST did not cause an over-constraint of the knee in any of the tested loading conditions.

CONCLUSION

In a combined ACL-reconstruction-MCL-repair model, MCL Repair augmented with suture tape improved valgus and external rotation laxity when compared to MCL suture repair alone. Suture tape augmentation may provide this additional means of stabilization and can be added at the time of surgical repair of the MCL. Clinically this may result in lower failure rates and less residual laxity after MCL repair, as well as shorter immobilization times and faster return to play.

Primary Repair of Anterior Cruciate Ligament Injuries: Current Level of Evidence of Available Techniques

»

Recently, there has been a resurgence of interest in primary anterior cruciate ligament (ACL) repair that has the potential to preserve native tissue using a more minimally invasive approach. Multiple repair techniques for different tear types have been reported over the last decade.

»

From a healing perspective, proximal tears can be reapproximated directly to the femoral wall because they have better intrinsic healing capacity than midsubstance tears. These procedures can be classified further as direct suture repair with or without static or dynamic augmentation. Current evidence does not support direct repair of midsubstance tears because of their limited healing capacity. In many instances, biological augmentation is needed to enhance the healing potential of the ACL.

»

While ACL repair is certainly not an effective surgical approach for all tears or in all patients, this procedure can be an effective and less morbid alternative to ACL reconstruction in carefully selected patients.

»

The overall current reported level of evidence of published studies has ranged from low to moderate, and thus there is a need for higher-quality, comparative studies in which outcomes of larger patient groups are compared with the current gold standard of ACL reconstruction.

Repair versus reconstruction for proximal anterior cruciate ligament tears: a study protocol for a prospective multicenter randomized controlled trial

Background

For active patients with a tear of the anterior cruciate ligament (ACL) who would like to return to active level of sports, the current surgical gold standard is reconstruction of the ACL. Recently, there has been renewed interest in repairing the ACL in selected patients with a proximally torn ligament. Repair of the ligament has (potential) advantages over reconstruction of the ligament such as decreased surgical morbidity, faster return of range of motion, and potentially decreased awareness of the knee. Studies comparing both treatments in a prospective randomized method are currently lacking.

Methods

This study is a multicenter prospective block randomized controlled trial. A total of 74 patients with acute proximal isolated ACL tears will be assigned in a 1:1 allocation ratio to either (I) ACL repair using cortical button fixation and additional suture augmentation or (II) ACL reconstruction using an all-inside autologous hamstring graft technique. The primary objective is to assess if ACL repair is non-inferior to ACL reconstruction regarding the subjective International Knee Documentation Committee (IKDC) score at two-years postoperatively. The secondary objectives are to assess if ACL repair is non-inferior with regards to (I) other patient-reported outcomes measures (i.e. Knee Injury and Osteoarthritis Outcome Score, Lysholm score, Forgotten Joint Score, patient satisfaction and pain), (II) objective outcome measures (i.e. failure of repair or graft defined as rerupture or symptomatic instability, reoperation, contralateral injury, and stability using the objective IKDC score and Rollimeter/KT-2000), (III) return to sports assessed by Tegner activity score and the ACL-Return to Sports Index at two-year follow-up, and (IV) long-term osteoarthritis at 10-year follow-up.

Discussion

Over the last decade there has been a resurgence of interest in repair of proximally torn ACLs. Several cohort studies have shown encouraging short-term and mid-term results using these techniques, but prospective randomized studies are lacking. Therefore, this randomized controlled trial has been designed to assess whether ACL repair is at least equivalent to the current gold standard of ACL reconstruction in both subjective and objective outcome scores.

Trial registration

Registered at Netherlands Trial Register (NL9072) on 25th of November 2020.

Role of Age on Success of Arthroscopic Primary Repair of Proximal Anterior Cruciate Ligament Tears

PURPOSE

To assess failure rates and patient-reported outcomes measures following arthroscopic primary anterior cruciate ligament (ACL) repair of proximal tears in different age groups.

METHODS

Between 2008 and 2017, the first 113 consecutive patients treated with repair were retrospectively reviewed at minimum of 2 years. Patients were stratified into 3 age groups: ≤21, 22-35, and >35 years. Primary outcomes were ipsilateral reinjury or reoperation, and contralateral injury rates, and secondary outcomes consisted of Lysholm, modified Cincinnati, Single Assessment Numeric Evaluation, International Knee Documentation Committee subjective, pain, and satisfaction scores. Group differences were compared using χ² tests and Mann-Whitney U tests.

RESULTS

Follow-up was obtained in 113 patients (100%). Median age was 35 years (interquartile range [IQR] 23-43) and median follow-up was 2.2 years (IQR 2.0-2.8). Overall, ACL reinjury occurred in 13 patients (11.5%), reoperation in 7 patients (6.2%), complications in 2 patients (1.8%) and contralateral ACL injury in 4 patients (3.5%). Overall, median Lysholm was 95 (IQR 89-100) and International Knee Documentation Committee subjective 92 (IQR 84-99). Treatment failure was significantly greater in the youngest age group (37.0%) as compared with the middle and older groups (4.2% and 3.2%, both P < .005). No significant differences were seen in reoperation, complication, or contralateral injury rates between groups (all P > .2), nor in patient-reported outcomes measures between the groups (all P > .1).

CONCLUSIONS

The failure rate of primary repair of proximal ACL tears is high in patients aged 21 or younger (37.0%), and this should be taken into account when discussing repair in this patient group. In patients older than 21, repair may be an excellent treatment with low failure (3.5%) and complication rates (1.2%) and good subjective scores.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Knotless Primary Anterior Cruciate Ligament Repair with Adjustable Loop Device and Internal Brace Augmentation

With the recent resurgence of primary anterior cruciate ligament repair, it is important to strive for optimal patient outcomes. This knotless primary repair procedure takes advantage of the use of an adjustable loop device, which allows for intraoperative retensioning by the surgeon. This technical advancement combined with augmentation with an internal brace could potentially minimize gap formation at the repair site, thereby increasing repair stability and ultimate outcome.

Large variation in indications, preferred surgical technique and rehabilitation protocol for primary anterior cruciate ligament repair: a survey among ESSKA members

PURPOSE

To assess current surgical preferences and practice patterns regarding primary anterior cruciate ligament (ACL) repair among European Society for Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA) members.

METHODS

A web-based survey was designed, including questions regarding indications for primary repair, outcomes of primary repair, and rehabilitation protocols. An invitation for study participation was sent by email to all ESSKA e-mail contacts. Descriptive statistics were performed.

RESULTS

A total of 169 surgeons responded to the survey (7% response rate of active members). Lack of supporting scientific evidence is the main reason for not using repair as a surgical treatment (63%). Most important indications were proximal avulsion tears (84%), younger age (49%), and older age (34%). Among those currently utilizing repair as a treatment option, transosseous tunnel fixation repair (34%) and repair with internal brace using transosseous tunnel fixation (32%) were the most preferred techniques. Eleven percent indicated dynamic intraligamentary stabilization as their preferred technique. A similar rate of progression for rehabilitation for repair and reconstruction techniques was noted among respondents.

CONCLUSION

This practice survey shows that the majority of surgeons indicated the main reason for not incorporating primary repair in their current practices was a lack of supporting scientific evidence. Among those holding favourable attitudes and beliefs, most surgeons indicated patients with proximal tears, younger-aged, and older-aged patients might be eligible for repair. Prospective studies with higher levels of evidence are warranted to establish guidelines for repair, including indications, optimal surgical technique, and rehabilitation protocols.

LEVEL OF EVIDENCE

V (expert opinion).