Editorial Commentary: Revision Knee Anterior Cruciate Ligament Reconstruction: Failure Rates Appear to Have Declined yet Different Research Methods Could Show Different Results

In the past decade there has been a rapid expansion in the available evidence for outcomes after revision knee anterior cruciate ligament reconstructions including data from 2 large registries and a growing body of research. The advent of 2 large registries and a growing body of evidence have provided a refined view of failure after revision reconstruction. A careful review of this evidence indicates that failure rates are not as high as previously reported in the literature. Because the body of literature continues to grow, the true role of graft selection on failure rates will become clearer and a more precise estimate of failure will emerge.     

Editorial Commentary: Repair the Anterior Cruciate Ligament When You Can: Add Suture Tape Augmentation and Dress for Success

Preserving the native anterior cruciate ligament (ACL) through primary repair has seen a resurgence over the past few years—rightfully so—given the inherent advantages of repairing the ACL over reconstruction. The issue is how best to repair the ACL and protect it to optimize healing. Suture tape augmentation techniques have shown promising low failure rates, and recent biomechanical studies have demonstrated benefits of the suture tape and optimal fixation methods for ACL repair. So, I believe it is time for orthopaedic surgeons to strongly consider routine suture tape augmentation use for improved outcomes with primary ACL repair.     

Editorial Commentary: Anterior Cruciate Ligament Costs Are Surprising

Given increasing health care costs and clinical equipoise on numerous topics, value calculations are critical. Cost-minimization analysis evaluates throughout a single episode of care. For anterior cruciate ligament reconstruction, this is a reasonable approach given that cost-effectiveness data have been published. Using Healthcare Cost and Utilization Project data, general anesthesia, anesthesia time, greater age, and medical comorbidities were correlated with higher costs. Among the surprising results were increased costs with male gender and Hispanic race. Interestingly, the location of the surgery, surgery center versus hospital, or meniscal repair did not significantly impact costs. This information can be used by physicians for cost comparison and factors that determine costs.     

Editorial Commentary: Revision of Failed Double-Bundle Anterior Cruciate Ligament Reconstruction

Double-bundle (DB) reconstruction of the anterior cruciate ligament was favored for several years. However, recent studies increasingly show that this technique does not provide a clear advantage over the less-invasive single-bundle technique. Unfortunately, the graft fails relatively often after ACL reconstruction. Postoperative communication of the bone tunnels through bone tunnel widening is possible. Since 2 drill channels are created in the DB technique, femoral as well as tibial, it is assumed that this technique may cause problems during revision. So, in part, revision may require a 2-step procedure with bone graft filling of the tunnels as the first step. It is important that surgeons with experience using DB publish their revision strategies and experiences.     

Editorial Commentary: Anterior Cruciate Ligament Repair Revisited … Do We Need A Paradigm Shift?

This commentary discusses a brief history of anterior cruciate ligament (ACL) repair using a variety of techniques, including open primary repair, arthroscopic repair, and bridge-enhanced ACL repair. Concerns are raised about the current reported outcomes of primary ACL repair. There is a need for controlled prospective studies that assess the structural integrity of the repaired ligament using modern imaging techniques, physical examination, and KT-1000 testing. Caution should be used when interpreting published studies that rely solely on patient-reported outcome measures.     

Editorial Commentary: The Anterior Cruciate Ligament Is a Dynamic Structure

The anterior cruciate ligament (ACL) is a dynamic structure composed of distinct bundles that function synergistically to facilitate normal knee kinematics in concert with bony morphology. Characterized by individual uniqueness, the ACL is inherently subject to both anatomic and morphological variations as well as physiologic aging. No locus on the lateral wall of the intercondylar notch is truly isometric through full range of motion, suggesting the ACL is a dynamic structure. Future studies should explore dynamic ACL behavior in vivo.     

Editorial Commentary: Osseous Anatomy of the Knee in Female Patients is a Significant Risk Factor for Anterior Cruciate Ligament Injury and Anterior Cruciate Ligament Graft Failure

Risk for anterior cruciate ligament (ACL) injury is greater in female than in male patients for a myriad of reasons, with osseous anatomy about the knee proving to be one significant risk factor for ACL injury and/or ACL graft failure. While femoral intercondylar notch size/shape and posterior tibial slope have been well-examined in this regard for their contribution to potential ACL injury, morphology of the lateral femoral condyle is a newer entity that may be linked to risk for ACL injury. Smaller/stenotic femoral intercondylar notches, increased posterior tibial slope of the lateral tibial plateau, and increased posterior condylar depth of the lateral femoral condyle have all been shown to increase risk for ACL injury and/or ACL graft failure. Such associations provide knee surgeons with food for thought when considering procedures such as notchplasty, staged anterior closing wedge high tibial osteotomy, and anterolateral ligament reconstruction/augmentation at the time of primary or revision ACL reconstruction. Further investigation into the links between pre-operative imaging parameters and outcomes following such concomitant procedures is required in order for any significant conclusions to be drawn.     

Editorial Commentary: Lateral Extra-Articular Tenodesis Reduces Anterior Cruciate Ligament Graft Rerupture Rates: Proper Anterior Cruciate Ligament and Lateral Extra-Articular Tenodesis Technique Is Vital to Prevent Complications

Lateral extra-articular tenodesis (LET) reduces anterior cruciate ligament (ACL) graft rerupture rates in high-risk patients. I believe in ilio-tibial band (ITB)-related LET to restrain anterolateral rotatory instability (ALRI) in ACL that is injured and reconstructed, and not in the “anterolateral ligament” or related techniques. However, the potential for conflict of a modified Lemaire LET femoral tunnel with an ACL femoral tunnel is higher than appreciated, and it risks iatrogenic ACL graft damage or compromised fixation. For MacIntosh LET, I use a staple to fix a strip of ITB (left attached distally to Gerdy’s tubercle) at the lateral femoral metaphysis. The tines of the staple are proximal to the ACL femoral tunnel and fixation, so conflict cannot occur. For modified Lemaire LET, the ITB graft is (taken deep to the LCL and) attached at “Lemaire’s point” on the lateral femur (proximal and posterior to the LCL femoral attachment). For fixation, I use a 15-mm length suture anchor, sufficiently short to avoid conflict. I presume fixation is less strong with sutures, so the 2-3 cm of ITB graft proximal to the suture are turned distally back over the LCL and sutured to itself. This does create a thickened contour to the lateral knee, but excellent clinical outcomes. Finally, I recommend the anteromedial bundle (AMB) position for the femoral tunnel, as in my experience in professional soccer players, using the central “anatomic” position increases rates of ACL graft rerupture. Moreover, “anatomic” femoral tunnel position results in a flatter trajectory increasing the risk of conflict with a LET tunnel (or lateral physical damage in patients with open growth plates).     

Editorial Commentary: Early Anterior Cruciate Ligament Reconstruction Decreases the Risk of Developing Irreparable Meniscus Tears in Female Athletes

There has been a substantial increase in the participation of women in sports since the passage of Title IX in 1972. With increased participation has come a rise in athletic injuries, including anterior cruciate ligament (ACL) tears. Numerous factors (modifiable and nonmodifiable) contribute to the 2 to 8 times increased risk of ACL tears in female compared with male athletes. The sports with the greatest risk of ACL injury include cutting sports such as soccer (1.1% per season), basketball (0.9% per season), volleyball, and lacrosse. In addition, female patients have a 33.7% greater risk of a subsequent contralateral ACL tear. Approximately 70% of ACL tears are the result of noncontact injuries. Numerous factors contribute to the increased risk of ACL tears in female athletes, including nonmodifiable (hormonal fluctuations, sex differences in knee geometry) and modifiable risk factors (neuromuscular control). Injury-prevention programs focus on modifiable risk factors and have been shown to be incredibly effective, decreasing the risk of ACL tears up to 50%. ACL tears commonly are associated with meniscus tears, including medial meniscus ramp and lateral posterior root lesions; therefore, thorough assessment is critical to identify this pathology. Early ACL reconstruction (i.e., <12 months following injury) increases the likelihood of being able to repair meniscus tears. Given the much greater risk of ACL tears and lower rate of return to sport in female athletes, this group warrants special attention to identify and treat these injuries earlier and subsequently improve overall outcomes.     

Editorial Commentary: Soaking Anterior Cruciate Ligament Grafts in Vancomycin Solution Lowers Infection Rates Without Lowering Functional Outcomes

Soaking anterior cruciate ligament grafts in vancomycin solution is done by many surgeons. Research has indicated decreased infection rates and similar anterior cruciate ligament retear rates between grafts soaked in vancomycin solution before implantation versus those without. In addition, there has been basic science evidence for tenocyte survival and viability even when exposed to vancomycin solution. The next frontier, investigating the maturation of vancomycin-soaked grafts with advanced imaging, may cause some surgeons to reconsider the practice but should not stop it, based on the available literature.     

Editorial Commentary: Understanding Anterior Cruciate Ligament Failure: New Questions Emerge as Existing Ones Are Answered

Cartilage injuries are prevalent in patients undergoing knee anterior cruciate ligament revision surgery.     

Editorial Commentary: Return to Play Following Revision Anterior Cruciate Ligament Reconstruction

In many cases, athletes return to play after anterior cruciate ligament (ACL) reconstruction. In such cases, after a second ACL tear, these athletes may again expert full return to play after ACL revision. Unfortunately, results after revision ACL reconstruction are inferior to results after primary surgery. Sport specific data is difficult to determine, as are predictors of positive outcomes which include concomitant pathology or psychological factors. Chances of return to the same level may be 60% or less.     

Editorial Commentary: Pursue the Anatomy of the Knee Anterior Cruciate Ligament Footprint

The paradigm of anterior cruciate ligament reconstruction has shifted from nonanatomic/isometric to anatomic reconstruction so as to mimic the native anterior cruciate ligament anatomy, as well as its function. A triple-bundle reconstruction technique more precisely mimics the native anterior cruciate ligament. On the other hand, functional advantages of triple-bundle reconstruction have not been fully elucidated. Comparative clinical studies between reconstruction techniques are needed.     

Editorial Commentary: Indications for Lateral Extra-Articular Tenodesis in Primary Anterior Cruciate Ligament Reconstruction

Lateral extra-articular tenodesis and other anterolateral procedures improve patient outcomes when combined with anterior cruciate ligament reconstruction. Failure rates are >50% lower in young patients at high risk of reinjury. We defined patients at high risk as those aged 14 to 25 years with 2 or more factors of the following criteria: 1) returning to contact pivoting sport, 2) high-grade anterolateral rotatory laxity, as measured by pivot shift test (grade 2 or higher), and 3) generalized ligamentous laxity (Beighton score greater than 4) or knee hyperextension recurvatum of greater than 10°. Other indications may include Segond fracture, chronic anterior cruciate ligament lesion, radiographic lateral femoral notch sign, and lateral coronal plane laxity. A clearer understanding of indications determined by a comprehensive clinical assessment and risk stratification is needed. As indications continue to be “stretched,” we need to better understand the role of lateral extra-articular tenodesis and when to employ it in our practice.     

Editorial Commentary: Revision Anterior Cruciate Ligament Using Soft Tissue Autograft Quadriceps Is Effective but Not Recommended for All Comers

The average revision rate is between 3.2% and 11.1%following primary anterior cruciate ligament (ACL) reconstructions,¹ and an objective failure rate of 13.7% has been reported for revision ACLR.² Prior implants, positioning of tunnels, and muscle weakness from the prior reconstruction present challenges. Additionally, graft choice for the revision reconstruction is restricted, depending on the primary reconstruction. Revision ACL reconstruction with the all-soft tissue quadriceps tendon autograft is a viable option with 83.3% of the patients surpassing the minimally clinically significant difference for International Knee Documentation Committee (IKDC) scores, which is similar to outcomes for revision ACL reconstruction (ACLR) using bone-patella-bone and hamstring tendon autografts. Furthermore, objective strength data suggest that it is possible to achieve equal limb symmetry index strength ratios even in the setting of prior bone-patella tendon-bone autograft. However, although I am cautiously optimistic regarding soft tissue quadriceps autograft in revision ACLR, I would be hesitant to recommend it for all comers. In my experience, young high school/collegiate female athletes with primary reconstruction using BPTB autograft may not be able to tolerate a secondary insult to the extensor mechanism via quadriceps tendon (QT) autograft harvest, where hematoma and arthrofibrosis could be concerns. Furthermore, increased posterior tibial slope may require evaluation and treatment, and the addition of a lateral extra-articular tenodesis may reduce residual rotatory laxity in ACL revision patients.     

Editorial Commentary: Tibial Attachment of the Anterior Cruciate Ligament: Just 1 Piece to the Complex Puzzle of Individualized,Anatomic Anterior Cruciate Ligament Reconstruction

The anterior cruciate ligament (ACL) is a complex, biologic structure that continues to be explored in the literature. Given the individual uniqueness of the ACL, variation exists, and studies continue to attempt to tease out what is truly important for ACL reconstruction. Although individual components of the ACL structure provide function, the ACL works as a dynamic structure, in unison with the surrounding bony morphology, to produce normal knee kinematics. Ultimately, in ACL reconstruction, the surgeon is tasked with restoring the native dimensions, collagen orientation, and insertion sites according to the individual anatomy.