Abstract
Background:
Anterior cruciate ligament (ACL) tears are a prevalent knee injury, often requiring surgery. While single-bundle reconstruction is the most employed technique for revision procedures, the native ACL consists of 2 anatomic bundles, and the double-bundle reconstruction technique aims to more accurately replicate this native anatomy. This video demonstrates a reproducible method for performing ACL reconstruction (ACLR) utilizing the double-bundle technique.
Indications:
Relative indications for revision double-bundle ACLR include revision or re-revision ACLR, previous lateral extra-articular tenodesis (LET), 2 to 3+ pivot shift, normal posterior tibia slope, and large lateral femoral condyles.
Technique Description:
Arthroscopic delineation of the ACL footprint is performed. With a curved, flexible reamer, the anteromedial socket is drilled. The posterolateral socket is reamed secondarily, providing a 2-mm bone bridge separating the 2 femoral tunnels. Two tibial tunnels are drilled under direct arthroscopic visualization. On the back table, a tibialis anterior allograft and bone–patellar tendon–bone allograft are prepared. The posterior bundle graft is initially passed. A cortical button is passed across the femoral cortex, and its position is confirmed. The anteromedial bundle graft is passed secondarily. Femoral fixation is established with a polyether ether ketone (PEEK) interference screw, and both grafts are fixed on the tibial side with a PEEK anchor. Standard closure follows, and the patient is placed in a hinged knee brace locked in extension.
Results:
A clinical trial including 81 patients with a mean 10.7-year follow-up indicated an 85% survival rate from needing a second revision ACLR when using an allograft. A meta-analysis by Seppänen et al indicated that the double-bundle technique was superior to the single-bundle technique in International Knee Documentation Committee subjective evaluations (P < .05). Another meta-analysis by Dong et al found no statistical difference in clinical outcomes between the single-bundle versus the double-bundle ACLR techniques.
Discussion/Conclusion:
Double-bundle ACLR offers significant anatomic and biomechanical benefits. In the context of re-revision ACLR, the double-bundle method provides additional collagen graft material and enhanced stability, especially in cases where concurrent LET has been performed and the posterior tibial slope remains normal.
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.
This is a visual representation of the abstract.
Keywords
Video Transcript
We present our technique for re-revision anterior cruciate ligament (ACL) reconstruction (ACLR) using a double-bundle technique.
The authors have no relevant disclosures for this presentation.
The following is an overview of our presentation.
Background
While single-bundle ACLR remains the standard of care in the United States, double-bundle ACLR is described and used due to its ability to more closely replicate the native ACL anatomy and kinematics of the knee. 6 While biomechanical studies favor double-bundle ACLR, clinical outcomes have not demonstrated clear superiority over single-bundle ACLR. 4 Double-bundle ACLR is also more technically demanding and time-consuming, as it requires precise drilling of additional tunnels, as well as preparation and harvesting of additional allograft or autograft tissue. 7 This case demonstrates the application and clinical value of double-bundle ACLR principles, in the context of a re-revision reconstruction.
Trends reported by the American Academy of Orthopaedic Surgeons in 2022 indicate that single- and double-bundle ACLR result in similar clinical outcomes. 4 The 2021 International Society of Arthroscopy, Knee Surgery and Orthopaedics Sports Medicine ACL Study Group Survey reported that surgeons performed 90% single-bundle versus 7% double-bundle procedures for primary ACLR. 4 For revision ACLR, the number of single-bundle procedures rose to 92%.10,11
The locations of double-bundle ACL tunnels are well established, and independent drilling of anteromedial (AM) and posterolateral (PL) bundles is an established technique. 3
Application of double-bundle concepts to revision ACLR and augmentation has been previously described, with the goal of re-creating 80% of the femoral insertion footprint. 9
Indications
We present the case of a 31-year-old male baseball player. While swinging a bat, he felt a pop within his left knee, followed by an effusion. He underwent 2 prior ACLR procedures: the most recent was performed 5 years ago using a bone–patellar tendon–bone (BTB) allograft with lateral extra-articular tenodesis (LET) with iliotibial band tissue. The index ACLR used a BTB autograft.
Physical examination was notable for a 2B Lachman test, 2+ positive pivot shift, joint effusion, and lateral joint line tenderness. His knee range of motion was from 0° to 130° of flexion.
Relative indications for revision double-bundle ACLR include revision or re-revision ACLR, previous LET, 2 to 3+ pivot shift, normal posterior tibia slope, and large lateral femoral condyles. Contraindications include insufficient bone stock of the femoral condyle or tibia tunnel widening >14 mm, smaller patient size or small lateral femoral condyle, and posterior tibia slope >13° in the setting of revision ACLR.3,5,7,8
A standard radiographic series of the knee was obtained, which demonstrated well-preserved joint space and no significant tunnel widening or degenerative changes.
Preoperative magnetic resonance imaging demonstrates evidence of the torn ACL graft. There was blunting of the inner free edge consistent with a chronic medial meniscus tear. Posterior tibial slope was normal at 8° within the medial compartment and 7° laterally.
After discussion of risks and benefits, the patient was indicated for double-bundle re-revision ACLR with BTB patellar and tibialis anterior allografts. Although single-bundle ACLR was also an option, double-bundle ACLR was indicated secondary to patient preference, normal tibia slope, previous LET, patient size, and failure of previously performed BTB autograft and allograft reconstructions. This flowchart outlines our decision-making process for double-bundle ACLR.2,9,10
Technique Description
The patient is positioned supine on a regular operating room table with a lateral post. A bump is placed distally to facilitate 90° of knee flexion. The surgeon for the procedure is right hand dominant.
Examination under anesthesia was notable for a grade 2B Lachman test and a 2+ positive pivot shift. Diagnostic arthroscopy within the medial compartment was notable for grade 1 chondromalacia. The meniscus was probed, and the absence of a ramp lesion was confirmed along the undersurface of the posterior horn. Within the notch, arthroscopic delineation of the ACL footprint was performed at 90° of knee flexion. The posterior bundle was outlined with the ArthroCare wand, followed by the AM bundle. The bifurcate and intercondylar ridges are clearly delineated. It is important to recognize that the ACL insertion on the wall of the lateral femoral condyle falls below the intercondylar ridge with the knee in 90° of flexion. Our goal is to fill over 80% of the native ACL footprint. 9
With a 40° curved flexible 8-mm reamer, the AM socket is drilled to a depth of 25 mm. The PL socket is reamed 5 mm in diameter to a depth of 25 mm, providing a 2-mm bone bridge separating the 2 femoral tunnels. The AM socket is notched with a hexagonal screwdriver to facilitate interference screw passage for the BTB allograft.
On the tibial side, a 4-cm incision along the AM tibia was made to remove retained tibial instrumentation. Viewing through the anterolateral portal, the PL and AM bundle center points are identified on the tibial origin. Two tibial tunnels are drilled under direct arthroscopic visualization. The AM tunnel was drilled with an ACL tip guide set to 65° within the AM footprint. The PL bundle tunnel was drilled at an angle of 45° within the PL bundle footprint. Note that a 2-cm bridge was maintained between the tibia AM and PL tunnel starting points, with the AM tunnel beginning more distal and anterior on the medial tibia cortex. 7 Debris was rongeured from the tibial side with a rongeur. Articular debris was removed with the shaver. This completed the femoral and tibial tunnel preparation.
On the back table, a 5-mm diameter tibialis anterior allograft was whipstitched and placed under 15 pounds of traction for 15 minutes. A self-tensioning suture loop button construct was attached to the graft for subsequent fixation. The tibialis anterior allograft was created with a bifid tail, to allow for possible interference screw placement on the tibial side. The AM bundle graft is a BTB construct. Due to the patient's height of 5′10′′, a 40-mm-long tendon graft was requested. 6 With a sagittal saw, the patellar plug was fashioned to measure 8 × 20 mm, and the tibial plug was cut to 8 × 30 mm. This completed the allograft preparation.
The posterior bundle graft is initially passed after the shuttling suture. A Kelly clamp and probe are used to facilitate graft passage. A cortical button is passed across the femoral cortex, flipped, tensioned, and positionally confirmed with a mini C-arm. The AM bundle graft is passed secondarily, and fixation is established with a 7 × 25-mm polyether ether ketone (PEEK) interference screw. The knee is cycled a dozen times. Fixation of both grafts on the tibial side is performed with the knee in 10° of flexion with a gentle posterior drawer force applied. Graft sutures are passed through a 4.75-mm PEEK anchor, and after predrilling with a 3.5 bit and advancing the tap, the anchor is deployed, and stable fixation is achieved. The AM bundle graft is reinforced on the tibial side with an 8-mm PEEK interference screw.
Arthroscopic evaluation confirmed anatomic reconstruction, and repeat examination under anesthesia was notable for a stable, grade 1A Lachman test and stable pivot shift. A standard closure was performed, and the patient was placed in a hinged knee brace locked in extension. 2
Results
Postoperative radiographs were obtained 1 week following surgery, delineating new tibia and femoral tunnels and an appropriately positioned cortical button.
Tips and Tricks: Pearls of this technique include an appropriate preoperative physical examination, paying careful attention to the presence of a large pivot shift and a positive dial test for PL corner instability. Prior incisions should be noted. Magnetic resonance imaging and a computed tomography scan should be obtained if tunnel widening is suspected. A deep understanding of instrumentation, drilling, and fixation techniques is necessary to perform this procedure successfully. If possible, prior operative notes and arthroscopic media should be obtained. 3
Care should be taken to appropriately identify the anatomic insertion points of the ACL bundles to maintain an adequate bone bridge between tunnels. 7 An accessory transpatellar portal will help with visualization of this step. Careful suture management should be performed to avoid issues with graft passage. Consider a notchplasty in the presence of lateral femoral condyle bony overgrowth. In the setting of significant tunnel widening greater than 14 mm, consider bone grafting and staging the procedure. 4
Pitfalls of this technique include a failure to maintain lateral femoral condyle and tibia bone bridges, difficulty with graft passage secondary to suture management and graft tunnel diameter mismatch, and failure to appropriately tension grafts. The PL bundle must be tensioned between 0° and 10° of flexion, and the AM graft may be tensioned between 0° and 45° of flexion. 7
Patients are initially fitted with a brace locked at 0° postoperatively. Physical therapy initially focuses on passive and active assisted range of motion. By 3 to 4 weeks, when patients have adequate quad control, brace range of motion (ROM) is increased to 0° to 30°. By 6 to 12 weeks, patients gradually increase to full ROM with an open hinge brace. At 5 to 6 months, patients progress with agility training. 2 By 9 months, patients may return to sport upon completion of a sport-specific return-to-play protocol.
Follow-up at 8 months postoperatively was notable for 0 of 10 pain and a Single Assessment Numeric Evaluation (SANE) score of 100% for activities of daily living. ROM of the left knee was 2° of hyperextension to 135° of flexion. The patient demonstrated a symmetrical single-leg hop. On examination, he had a grade 1A Lachman test, and a stable pivot shift was noted. Manual resistance lower extremity strength testing was 5 of 5 throughout.
Macchiarola et al 5 published a retrospective cohort analysis studying outcomes of 81 double-bundle ACLR with an Achilles tendon allograft, with a mean follow-up of 11 years. There was an 85% survival rate from needing another ACLR and a 68% survival rate from needing subsequent knee surgery. Forty-eight percent were back to performing at the same level of sport activity before the graft failure.
A meta-analysis by Seppänen et al, 8 which included 40 studies, analyzed double-bundle versus single-bundle ACLR. When comparing the double-bundle versus the transtibial single-bundle technique, they found that the double-bundle technique was superior in improving knee laxity and subjective outcomes. Specifically, KT-1000/2000, International Knee Documentation Committee (IKDC) subjective evaluation, Lysholm scores, pivot shift, and IKDC objective evaluations were significantly better. In comparing double-bundle versus medial portal single-bundle reconstructions, no significant differences were found.
Despite purported anatomic, biomechanical, and kinematic advantages of double-bundle ACLR versus single-bundle ACLR, clinical outcomes have generally failed to show clear superiority of one technique versus the other. Dong et al 1 performed a meta-analysis of randomized controlled trials comparing single- versus double-bundle ACLR, including 294 patients. The authors found no statistically significant differences between the 2 techniques regarding patient-reported outcome scores (Lysholm, IKDC) and concluded that they were of similar efficacy.
Discussion/Conclusion
In conclusion, double-bundle ACLR may be indicated for surgeons familiar with the technique as it confers significant anatomic and biomechanical advantages. In the setting of re-revision ACLR, it provides additional collagen graft and excellent stability, especially if concurrent LET has already been performed and posterior tibial slope falls within the normal range.1,5,8
These are our references.
Thank you for taking the time to watch our video.
Footnotes
Submitted October 21, 2024; accepted February 19, 2025.
One or more of the authors has declared the following potential conflict of interest or source of funding: B.F. is a board or committee member for AOSSM; receives research support from Arthrex, Smith & Nephew, and Stryker; is a paid consultant for Smith & Nephew and Stryker; receives publishing royalties, financial, or material support from Elsevier; has stock or stock options with iBrainTech, Sparta Biopharma, and Zuno Medical; and is on the editorial or governing board for Video Journal of Sports Medicine. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
