Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction Using the Anatomic Double-Bundle 2-in-1 Guide System

Abstract

Background:

In double-bundle anterior cruciate ligament (ACL) reconstruction, tunnel coalition may occur intraoperatively or during the postoperative course. Tibial tunnel coalition is more common compared with femoral tunnel coalition. Once tunnel coalition occurs on the tibial side, rotatory knee laxity may not be controlled as expected. We have developed a new device to avoid tibial tunnel coalition with consistency. The purpose of this video is to present the surgical technique for double-bundle ACL reconstruction using a new drill guide.

Indications:

The novel guide may be used in all cases with confirmed ACL tear in a physically active patient, identical to indications for current ACL reconstruction using the double-bundle technique.

Technique Description:

The hamstring tendon is harvested for the ACL grafts. Two guide pins for the anteromedial bundle and posterolateral bundle for the tibial tunnel are inserted through the Anatomic Double-Bundle 2-in-1 Guide System. Cannulated drills and dilators are used to create the tunnel to the final diameter. Next, femoral tunnels are created by the outside-in technique using the Anatomic Double-Bundle 2-in-1 Guide System. Grafts are inserted from the tibia and passed through the femur. The grafts are fixed with a post screw and/or interference screw.

Results:

Two weeks after surgery, no tibial or femoral coalition (0/20 cases) were confirmed and tibial bony bridge at the intraarticular surface was measured 2.7 ± 0.9 mm using computed tomography (CT). One year after surgery, tibial coalition was confirmed in 13.3% (2/15 cases), and femoral coalition in 6.7% (1/15 cases) on CT image mainly due to tunnel widening. The 2 cases with tibial coalition had tibial bony bridge of less than 2 mm on immediate postoperative CT.

Discussion/Conclusion:

Using the novel guide, 2 tibial tunnels were created easily and accurately compared with the conventional independent drilling technique. The 2 tunnels can also be created simultaneously with single placement of the guide. Two separate tunnels help maintain expected rotatory knee stability after double-bundle ACL reconstruction.

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.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

This surgical video will introduce the surgical technique for anatomic double-bundle anterior cruciate ligament (ACL) reconstruction using an Anatomic Double-Bundle 2-in-1 Guide System. There was no commercial support for the contents of this video. The video will start with the background for using the new drill guide system followed by preoperative planning and a surgical video. Potential complications, postoperative management including rehabilitation protocol, and patient outcome will be discussed.

Double-bundle ACL reconstruction is not synonymous with anatomic ACL reconstruction. ² The “anatomic” double-bundle ACL should have independent posterolateral (PL) and anteromedial (AM) bundles functioning differently. However, tunnel coalition may occur due to technical error or postoperative tunnel enlargement,^1,5 especially on the tibial side. A recent systematic review has reported a pooled rate of 21% tibial coalition rate compared with 8% on the femoral side. ³ Coalition of 2 tunnels function similarly to a single tunnel, ⁴ thus highlighting the importance of creating 2 separate tunnels for both femoral and tibial sides.

Surgical indication and contraindications for this technique are the same as for a typical adult ACL reconstruction. We will present a case of a 20-year-old male complaining of right knee pain and instability. He sustained a right knee twisting injury during basketball and was diagnosed with ACL injury. He was referred to our hospital for surgical treatment. On examination, his right knee was quiet with full range of motion (ROM). He had a positive Lachman and pivot-shift test. Varus and valgus stress tests were negative and also posterior drawer test was negative. McMurray test was also negative. Preoperative radiograph shows no abnormal findings, and the magnetic resonance imaging sagittal view of the knee shows the ACL torn from the femoral attachment.

This is the 2-in-1 drill guide. The guide allows a single-step procedure for drilling 2 tunnels in the femur or tibia. The guide also ensures a 2-mm bone bridge between the AM and PL tunnels to prevent coalition intraoperatively. The picture on the left shows the 2 mm width between the aperture of the AM and PL tunnels. The guide set shown on the right comes with 3 variations of sizes, ranging from a combination of 5 to 6 mm for the PL tunnel, and 6 to 7 mm for the AM tunnel for the right and left knees.

For tunnel positioning, as it will be shown later in the video, the resident's ridge and bifurcate ridge are identified and used as a reference in combination with the ACL remnant for the femoral tunnels. For the tibial tunnel, the AM bundle is placed just posterior to the Parson's knob and the PL bundle, anterior to the intersection of the line tangent to the posterior edge of the lateral meniscus and the medial tibial eminence.

Patient leg is set with a knee holder and tourniquet around the thigh. The knee is positioned at 90° of flexion. The bony landmarks are shown here. We use parapatellar portals for scoping and an oblique skin incision is made just above the pes anserinus for graft harvesting and tibial tunnel drilling.

An oblique skin incision is made just above the pes anserinus. Gracilis and semitendinosus tendons are marked, and tendon stripper is used for harvesting. Arthroscopic examination shows no meniscus tear in the medial compartment. Also, no ramp lesion is seen. There is a small radial tear in the middle part of the lateral meniscus. Partial meniscectomy is performed. The ACL remnant is identified and debrided. We routinely switch to the medial portal to identify the femoral footprint of the ACL. We use a radiofrequency device to remove the ACL remnant from the femoral attachment. Now, we can clearly see the femoral footprint of the ACL. The bifurcate ridge in this case is clear. Each PL and AM bundle footprints can be identified. The tibial footprint is viewed from the lateral portal. We trace the posterior edge of the lateral meniscus anterior horn up to the medial tibial eminence where the PL bundle target is located as shown. Parson's knob is palpated by probing and the target for the AM bundle is just posterior. The tibial guide is inserted through the medial portal and set at the earlier identified target. Guide pin is drilled though the guide, first for the PL followed by the AM tunnel. A cannulated drill is used to drill the tunnels, again, PL first. The PL diameter was 6 mm for this case. A 6-mm dilator is inserted. A 7-mm diameter cannulated drill is used for the AM bundle. Again, same-size dilator, 7 mm, is inserted. After clearing the debris of the ACL remnant, the 2 independent tunnels at the target locations can be seen. The femoral guide is held at the earlier identified AM and PL footprints and the cannulas are inserted. The guide pins are inserted, PL first and then the AM. The tunnel lengths are measured. A 4.5-mm cannulated drill is used to drill through the lateral femoral condyle. A 5-mm-diameter retrograde drill for the PL bundle in this case is manually inserted through the tunnel. A 15-mm socket is drilled in a retrograde fashion and carefully measured. The drill is then pushed back to close the cutter and retrieved. The guiding suture is immediately inserted through the cannula. Then, the suture is pulled out with a grasper from the tibial tunnel. The same procedure is performed for the AM bundle. The size of the tunnel diameter was 6 mm for this case. This is the completed graft with an adjustable loop suspension device for the femoral side fixation and sutures on the tibial side. The graft is passed through the tunnels. First, for the PL bundle, the sutures are relayed to guide the graft into the tunnel from the tibia through the lateral femoral condyle. The button is then flipped. Next, the adjustable loop is pulled to draw the graft through the joint into the femoral socket sufficiently. The same procedure was performed for the AM bundle. The final arthroscopic view is shown. The postscrew is inserted 2 cm distal from the tibial tunnels. Starting with PL bundle fixation, the knee is held at full extension and tensioned with manual maximum force. For the AM bundle, the knee is held at 20° of flexion. Finally, the postscrew is tightened.

The postoperative plain radiograph is shown with cortical buttons on the femoral side and postscrew in the tibia.

There are a few potential complications and pitfalls. First, guide placement is dependent on portal placement. If the portal is too medial or lateral, too high or low, it may be difficult to place the guide on the targeted area. For such cases, it may be necessary to extend the incision of the portals accordingly. Next, size variation for the guides is still limited. As presented earlier in the video, there are only 3 different combinations of sizes between 5 and 7 mm. In our experience, we rarely encounter cases in which the graft diameter is smaller or larger than the available guides. Finally, tunnel coalition or disruption of the bony bridge may occur postoperatively due to tunnel expansion.

Partial weightbearing is allowed immediately after the operation and full weightbearing is allowed after 2 weeks. We allow ROM as tolerated. Return to sport is decided based on muscle strength and functional test results. Usually, greater than 90% performance compared with the contralateral healthy knee is required. The minimum time to return to sport is 6 months; however, we encourage greater than 9 months.

Postoperative computed tomographic (CT) assessment at our hospital showed that at 2 weeks postoperation, no tibial or femoral coalition was seen out of 20 cases and the average bony bridge between the AM and PL bundles at the tibial articular surface was 2.7 mm. At 1 year postoperation, 2 out of 15 cases had tibial coalition, and 1 case had femoral tunnel coalition. The 2 cases with tibial tunnel coalition had a tibial bony bridge less than 2 mm on the 2 weeks postoperative CT.

Surgical technique using a new drill guide system for double-bundle ACL reconstruction using hamstring tendon was introduced. Two anatomic tunnels were separately created in the femur and tibia with high consistency. Therefore, the “true effect” of the double bundle can be expected. References are as listed.