Primary anterior cruciate ligament (ACL) reconstruction has satisfactory outcomes in 75% to 97% of patients.1-3 Despite this high success rate, the number of revision ACL reconstructions has risen4 and is likely underreported.5 Recurrent instability occurs if the reconstructed ligament fails to provide adequate anterior and rotational knee stability. Causes of graft failure include repeat trauma, early return to high-demand activity, poor operative technique (including poor graft placement), failure to address concomitant pathology, and perioperative complications (eg, infection, stiffness).4 In addition, most patients who have revision ACL reconstruction received autograft tissue in the initial surgery, and allograft is thus not uncommon in revision ACL surgery. Allograft tissue has longer incorporation times6 and increased incidence of recurrent postoperative instability when compared with autograft tissue.7 Extra-articular tenodesis may thus be used to provide additional stability to the revision allograft tissue while it incorporates.
In this article, we describe our use of an extra-articular iliotibial band (ITB) tenodesis as an augmentative procedure in patients undergoing revision ACL reconstruction with bone–patellar tendon–bone (BPTB) allograft.
Surgical Technique
After induction of anesthesia and careful positioning, the patient is prepared and draped in the usual sterile fashion. Standard anteromedial, anterolateral, and superolateral outflow portals are established, and diagnostic arthroscopy is performed to inspect the cruciate ligaments, menisci, and articular cartilage (Figure 1). Peripheral meniscal tears should be repaired (Figure 2), and central or inner tears should be débrided to a stable rim. If meniscal repair is performed, sutures should be tied at the end of the case. Unstable articular cartilage defects should also be débrided. An 8- to 12-cm lateral hockey-stick incision is then made from the Gerdy tubercle to the inferior edge of the lateral femoral epicondyle in preparation for the ITB tenodesis (Figure 1). The lateral collateral ligament (LCL), the lateral head of the gastrocnemius, and the ITB are identified. The peroneal nerve should be significantly distal to the working field.
Remnants of the previous ACL graft are débrided, and, if necessary, a modified notchplasty is performed. A position for the new femoral tunnel is located and is confirmed with intraoperative fluoroscopy. This tunnel is established with compaction drill bits and dilated to the appropriate diameter through the anteromedial portal with the knee in 120° of flexion.
BPTB allograft is prepared first by cutting its central third to the desired diameter (Figure 3). The bone-plug ends are prepared with compaction pliers. Two 2.0-mm drill holes are made in each of the allograft bone plugs, and a No. 5 Ti-Cron suture (Covidien, New Haven, Connecticut) is placed through each of the holes. We typically use 2 sutures on each bone plug.
A tibial tunnel is then established with an ACL drill guide under arthroscopic visualization and intraoperative fluoroscopy for confirmation of correct pin placement. We use Kirschner wires (with parallel pin guides as needed), compaction drills, and dilators to create a well-positioned tunnel of the appropriate diameter. The allograft is then passed through the tibia and femur in retrograde fashion. We secure the femoral side with an AO (Arbeitsgemeinschaft für Osteosynthesefragen) 4.5-mm bicortical screw and washer. Our tibial fixation is secured after the ITB tenodesis. The knee is then cycled a dozen times.
In preparation for the ITB tenodesis, we lengthen our previously made incision by about 4 cm proximally along the posterior aspect of the ITB. The central portion of the ITB is then outlined at the Gerdy tubercle and split with a No. 10 blade. This generally leaves an approximately 12- to 14-mm strip of ITB centrally (Figure 4). This portion should be gently lifted from the underlying tissue attachments distally at the insertion on the Gerdy tubercle. The interval between the LCL and lateral capsule of the knee is identified, and a No. 2 Ti-Cron whip-stitch is thrown through the free end of the ITB graft (Figure 5). The anterior aspect of the femoral tunnel is at the distal aspect of the lateral femoral condyle, and the posterior aspect is at the juncture of the proximal LCL and the lateral head of the gastrocnemius. The cortices of these landmarks should be perforated with a drill, and a curved instrument should be used to create a bone tunnel at this location (Figure 6). The tibial tunnel is just posterior and distal to the Gerdy tubercle and should be created in similar fashion. The graft is then passed underneath the LCL (Figure 7), through the proximal tunnel that has been created on the lateral femoral condyle, and then back down through the LCL and back onto itself after exiting the tibial tunnel (Figure 8). With the knee at 30° of flexion, the ITB graft is tensioned and sutured down to intact ITB fascia just proximal to the tibial tunnel orifice (Figure 9). We check knee range of motion (ROM) and then perform a Lachman test to assess changes in knee stability. The pivot shift examination is omitted to avoid placing excessive stress on the tenodesis. The tibial side of the patellar tendon allograft is then tensioned and secured over an AO 4.5-mm bicortical screw with washer with the knee in full extension. The screw is then tightened at 30° of knee flexion.
