Surgical Techniques in Sports Medicine
1st Edition

Surgical Considerations with Failed Posterior Cruciate Ligament Surgery
Michael K. Gilbart MD
Champ L. Baker III MD
Christopher D. Harner MD
History of Technique
Knowledge of the posterior cruciate ligament (PCL) has been slowly improving due to studies on its anatomy and biomechanics. Controversy exists concerning the most appropriate treatment, especially in cases of isolated PCL injury. For those patients who have had a PCL reconstruction that unfortunately progresses to failure, there is a paucity of literature published on the potential mechanisms of failure and available treatment options. A PCL reconstruction failure may consist of a combination of subjective factors of pain, instability, or stiffness as well as objective findings of laxity, progressive degenerative changes, or loss of motion. Residual laxity generally occurs in the posterior and posterolateral directions, and degenerative changes usually occur in the medial compartment.1,2
The causes of failure of the PCL reconstruction should be identified. Failures may be classified as primary or secondary. Primary failures are generally caused by inadequate surgical technique, such as failure to recognize and treat combined instabilities, improper tunnel placement, inadequate graft tensioning or fixation, or incomplete initial management of meniscal and articular pathology. Secondary failures may be caused by inadequate biology and graft healing, overly aggressive rehabilitation protocols, repetitive trauma, or patient noncompliance. Noyes and Barber-Weinstein3 recently reported on multiple causes of failure following PCL reconstruction in 41 patients and found the presence of untreated posterolateral corner injury in 41% of patients, improper tunnel placement in 39%, and untreated varus malalignment in 27% of patients.
Revision PCL reconstructions should be adequately planned prior to surgery. The operative considerations include graft selection, the use of one- or two-bundle techniques as well as the option of either a transtibial or tibial inlay technique. Other considerations include the location of femoral tunnels, graft tensioning and fixation, the treatment of combined instabilities, treatment of pre-existing meniscal or articular pathology, and the necessity of performing a high tibial valgus osteotomy (HTO).
Principles of Management
The clinical examination is extremely important in the evaluation and creation of a management plan for failed PCL reconstruction. Patient evaluation should consist of a thorough preoperative history and physical examination, including a review of all patient records and operative reports. It should be determined whether the main subjective patient complaint is one of pain or instability.
The physical examination should help the clinician evaluate for potential causes of failure of the PCL reconstruction.2 An evaluation of knee range of motion as well as an evaluation of primary and secondary restraints should be performed. Specifically, does the objective evaluation demonstrate a problem with increased laxity or decreased range of motion?
The knee should be evaluated for the presence of a positive posterior drawer, quadriceps active test, or Godfrey test (flexion of hip and knee to 90 degrees, a positive test is posterior displacement of tibia).2 The knee should be evaluated for fixed posterior tibial subluxation. It is critical to recognize any associated, untreated combined instability, as studies have shown that leaving such instabilities untreated will cause increased in situ forces on the PCL and increased failure rates of PCL reconstructions.4,5,6 It is generally recognized that if there is excessive posterior translation of the tibia on examination (grade 3, or >10 mm), one must rule

out an associated posterolateral corner injury.7 This can be assessed using the tibial dial test at 30 degrees and 90 degrees of knee flexion. Increased tibial external rotation at 30 degrees is consistent with an isolated posterolateral corner injury, while increased external rotation at 30 degrees and 90 degrees is indicative of a combined PCL/posterolateral corner injury.2
Standing limb alignment should be assessed, including the recognition of any associated bony deformity. Gait should be evaluated for the presence of a varus thrust or excessive recurvatum. One may need to first address this varus alignment, as the presence of a varus deformity stresses the posterolateral structures excessively, leading to failure of the ligament reconstruction. In this situation an anteromedial opening wedge (biplanar) osteotomy is indicated for correction of the varus deformity and also to increase the posterior tibial slope.8 An increase in the tibial slope has been found to cause an anterior shift in the resting position of the tibia, and this is beneficial in reducing the posterior tibial sag in PCL deficient knees.9 In general, the biplanar osteotomy is indicated for patients with medial joint line pain with activities of daily living, varus malalignment of the mechanical axis of the knee, and residual PCL laxity. If there is no associated posterolateral corner injury, one should re-evaluate the patient after allowing an adequate amount of time for the biplanar osteotomy to heal, as some of these patients may not require definitive PCL revision.
It is important to perform a thorough evaluation of the neurovascular status of the affected extremity with special attention to the presence of any pre-existing injury to the popliteal vessels or peroneal nerve. An arteriogram is recommended and should be performed preoperatively for any patient with concerns about a potential preoperative vascular injury. We strongly recommended that when there is any doubt about the vascular status of the extremity, one should obtain a preoperative arteriogram.
Fig. 47-1. Stress radiograph illustrates posterior subluxation, but may also be helpful to determine presence of fixed posterior subluxation.
One should make note of any prior skin incisions, as these are important to consider during the planning of any future surgery.
A routine knee series including PA flexion weight bearing (45 degrees), lateral radiographs, Merchant views, and a long cassette should be obtained. Stress radiographs may be useful, especially for those patients with suspected fixed subluxation (Fig. 47-1). Radiographs allow evaluation of tunnel position and size, position of hardware, degree of subluxation, and associated pathology. Preoperative magnetic resonance imaging (MRI) is helpful for detecting any meniscal pathology or articular cartilage abnormalities.
Indications and Contraindications
The indications for a revision PCL reconstruction include a patient with a previous failed PCL reconstruction and continued symptoms of pain and instability. A thorough preoperative assessment for associated instabilities should be undertaken, and these should be addressed along with the PCL revision reconstruction. Relative contraindications for surgery include a severe preoperative loss of range of motion and a fixed posterior drawer (one that cannot be reduced manually).8 Absolute contraindications for PCL reconstruction include advanced osteoarthritis of the knee or active infection.
The surgeon should take into consideration the reliability and compliance of the patient prior to revising a PCL reconstruction. The surgeon must adequately counsel each patient through the informed consent process and should offer a realistic perspective of the expected outcome, the complexity of the surgery, and the associated risks. Patients should be aware that the results of revision and salvage PCL reconstructions may not be as good as a primary PCL reconstruction.
Surgical Techniques
The technique of reconstruction required is dependent upon the etiology of the PCL failure and the patients’ symptoms. Surgery may be performed as a one- or two-stage procedure. If the previous tunnels show excessive widening and resorption, the fixation hardware should be removed and the tunnels bone grafted and allowed adequate time to heal and incorporate (usually 6 months).
Biplanar Opening Wedge High Tibial Osteotomy
Preoperative templating using standing long cassette radiographs is essential. The planned osteotomy should be

drawn, and an estimate of the proximal tibial width and necessary plate size should be made by taking radiographic magnification into account. The width of the opening wedge osteotomy on the tibia is determined by the degree of desired correction.
The patient is placed supine on the operating table. The preferred anesthesia is a combination of regional femoral and/or sciatic nerve block with a laryngeal mask anesthetic. The landmarks on the knee must be drawn, including the inferior pole of the patella, tibial tubercle, joint line, fibular head, a Gerdy tubercle, and the peroneal nerve. We use a Bovie cord and C-arm to mark a straight line from the center of the hip to the center of the ankle, noting its position as it crosses the knee joint (medial to the tibial spine in a varus knee).
An incision is made midway between the medial border of the tibial tubercle and the posterior border of the tibia. The incision begins 1.0 cm inferior to the joint line and extends approximately 5 cm distally. Exposure is made down to the superficial fibers of the medial collateral ligament (MCL), and subcutaneous flaps are created to allow exposure of the patellar tendon and the tibial tubercle. The patellar tendon is then retracted laterally. An incision is then made in the sartorius fascia just superior to the gracilis tendon, and a subperiosteal dissection is completed superiorly to release the superficial fibers of the MCL off of bone. Care must be taken to stop the subperiosteal dissection just distal to the joint line, to preserve the deep fibers of the MCL.
A tibial guide wire is placed from an anteromedial to a posterolateral direction angled 15 degrees cephalad along the proposed osteotomy, and its position is confirmed with the C-arm. The line of the osteotomy should be just superior to the tibial tubercle. The width of the proximal tibia should then be confirmed using a free K-wire to confirm that the actual tibial width at the osteotomy site matches the templated tibial width on preoperative radiographs. This allows for the surgeon to confirm an adequate tibial osteotomy correction will be performed. A 1-inch osteotome is recommended to start the osteotomy, using the K-wire as a directional guide. Once the osteotomy plane is initiated, the K-wire may be removed and the osteotomy completed using an oscillating saw or osteotome, taking care to protect a posterolateral hinge of cortical bone for stability. To safely complete the osteotomy across the posterior tibial cortex and to protect the neurovascular structures, the surgeon must angle the osteotome to avoid excessive perforation of the posterior cortex.
Fig. 47-2. Postoperative (A) AP and (B) lateral radiographs after biplanar osteotomy and plate fixation.
The Arthrex (Arthrex Inc, Naples, FL) opening wedge osteotomy system is used, and the wedge device is inserted into the osteotomy site to create the desired angle of correction. If added distraction is required, a laminar spreader may be used in the osteotomy, but it is best placed anteriorly under the thick bone of the tibial tubercle to prevent damage to the metaphyseal bone. The appropriate plate is then selected and placed in the anteromedial aspect of the osteotomy for a biplanar effect. The alignment of the leg is again checked using the Bovie cord and C-arm from the center of the hip to the center of the ankle in order to ensure that it crosses the knee joint lateral to the tibial spine, indicating an adequate correction. The plate is then fixed proximally with two cancellous screws directed parallel to the articular surface. Distally the plate is secured with 4.5 mm self-tapping screws with purchase into the lateral cortex (Fig. 47-2). Wedge cuts of femoral head allograft are fashioned to bone graft the osteotomy site. The superficial MCL is sutured down to the medial tibial

metaphysis using suture anchors. Wound closure is achieved using a no. 0 absorbable suture, followed by no. 2-0 absorbable interrupted sutures. Skin is closed using skin staples.
Posterior Cruciate Ligament Reconstruction (Transtibial Tunnel Technique)
Our preferred method is a reconstruction using a transtibial technique and double-bundle PCL reconstruction of both the anterolateral (AL) and the posteromedial (PM) PCL bundles. This type of double bundle PCL reconstruction is technically challenging, but effectively reproduces intact knee kinematics and in situ forces of the knee.6,10,11,12,13 There are many grafts available for selection, including allograft and autograft. Our preferred grafts for reconstruction of the PCL include a semitendinosis tendon autograft for reconstruction of the posteromedial bundle and an Achilles tendon allograft for reconstruction of the anterolateral bundle, with or without a calcaneal bone block on the femoral side.
The patient is positioned supine on the operating table. The preferred anesthesia is a combination of regional femoral and/or sciatic nerve block with a laryngeal mask anesthetic. The operative knee is examined under general anesthesia and a comparison is made to the contralateral knee. An outflow portal is first placed in a superolateral location, followed by the standard anteromedial and anterolateral portals for arthroscopic visualization and instrumentation. A thorough, systematic arthroscopic examination of the knee is then performed.
The intercondylar notch is debrided of the PCL remnant using a 5.5 mm shaver to allow visualization of the notch and the femoral PCL footprint. A 70-degree arthroscope is placed through the anterolateral portal to the posteromedial corner of the notch in order to visualize the PCL tibial footprint, posterior horn medial meniscus, and posteromedial capsule. A posteromedial portal is then created under direct visualization through which the shaver is introduced to debride the posterior tibial PCL footprint. It is important to direct the shaver anteriorly toward the tibia at all times to protect the posterior neurovascular structures. Using the 30-degree scope for visualization through the posteromedial portal, the angled PCL rasp and curette are introduced through the anteromedial portal to elevate the posterior capsule and fully expose the PCL tibial footprint. The elevation of the capsule and PCL footprint debridement allows for adequate visualization and aids in correct tunnel placement.
The arthroscopic PCL guide is placed in the anteromedial portal with the tip positioned at the location of the PCL tibial footprint. The drill guide is set at 50 degrees. The guide wire sleeve is advanced to leave a mark on the skin of the anteromedial proximal tibia at a point midway between the anterior tibial crest and the posteromedial border of the tibia. A 3-cm longitudinal skin incision is made over the mark with exposure created directly to bone. This incision is generally initiated at the superior border of the tibial tubercle and extends distally. The 30-degree scope is placed in the posteromedial portal and the guide wire is drilled under direct arthroscopic visualization. The position of the wire is checked with C-arm fluoroscopy (Fig. 47-3). The tibial tunnel is created by reaming over the guide wire and then dilating the tunnel to an appropriate size. The guidewire tip is protected from advancing posteriorly during drilling by placing an angled curette over the tip of the guide wire.
Fig. 47-3. Transtibial guide wire placement checked intraoperatively using C-arm fluoroscopy.
In the case of revision chronic PCL tears a two-tunnel reconstruction is generally preferred. The sites of the anterolateral and posteromedial tunnels are marked using an intra-articular Bovie, at the 11:00 and 8:30 positions, respectively for a left knee (Figs. 47-4, 47-5, 47-6).7,8,14 The femoral tunnel guide wire is then placed through the anterolateral portal (Fig. 47-7). The femoral tunnels are then drilled using an acorn drill to a depth of 25 mm and a diameter that is 1 mm less than the prepared anterolateral and posteromedial PCL grafts. These tunnels are then dilated an additional 1 mm over the drilled diameter to match the diameter of the grafts. A 4.5-mm EndoButton drill bit is then used to penetrate the medial femoral cortex. All the soft tissues are removed from around the tunnel entrances to allow for smooth passage of the grafts. A 3-cm oblique incision is made directly over the medial femoral condyle to allow for later fixation with the EndoButton. Care is taken to split the vastus medialis in line with its fibers and not to violate the muscle excessively.
The preferred grafts are an Achilles tendon allograft of 10- to 11-mm diameter to re-create the AL bundle and a semitendinosus autograft of 6- to 8-mm diameter for reconstruction of the PM bundle (Fig. 47-8). The Achilles tendon allograft is prepared to a total graft length of 25 cm and a

calcaneal bone block length of 25 mm. The bone block is shaped into a cylindric shape of the appropriate size using an oscillating saw and a rongeur. The soft tissue edges of the tendon are trimmed, and the tendinous portion of the graft is tubularized with a no. 5 Ticron whipstitch suture. The semitendinosus tendon is harvested in the standard fashion, and its ends are sutured using a no. 5 Ticron whipstitch. The semitendinosus is looped over an EndoButton for later femoral fixation.
Fig. 47-4. Location of anterolateral and posteromedial bundle insertion site in intercondylar notch (left knee).
Fig. 47-5. Intra-articular view of proposed 11:00 (AL, anterolateral) and 8:30 (PM, posteromedial) tunnel positions (left knee).
Fig. 47-6. Intraoperative pictures of anterolateral (AL) and posteromedial (PM) graft tunnel preparation sites (left knee).
For graft passage a malleable wire is inserted through the tibial tunnel and is captured with a grasper placed through the anterolateral portal. The wire loop is then used to pass the soft tissue portion of the Achilles graft through the anterolateral portal, into the intercondylar notch, and down the tibial tunnel. The calcaneal portion of the Achilles graft is then passed through the femoral tunnel using a Beath pin. The semitendinosus graft is introduced in a similar fashion. There are a variety of fixation techniques for these two grafts on the femoral side, including EndoButton or fixation over a post. The AL bundle graft is tensioned at 90-degrees knee flexion and the PM bundle graft is tensioned at 30 degrees of knee flexion (in both cases an anteriorly directed force is placed on the tibia). Both grafts are fixed on the tibial side by tying over a 4.5-mm cortical screw post, with a 14-mm soft tissue washer for the anterolateral graft and a 7-mm washer for the posteromedial graft. After both grafts are tensioned and fixed with a screw and washer, an 8-mm

absorbable interference screw is then introduced into the tibial tunnel for additional fixation (Fig. 47-9). Wound closure is performed using no. 0 absorbable interrupted sutures, followed by no. 2-0 absorbable interrupted sutures and staples to approximate skin. The tibial inlay technique is described elsewhere in this text as well as in Johnson et al.7
Fig. 47-7. Location and angle of guide wire placement for the femoral tunnel through the anterolateral portal.
Fig. 47-8. Achilles tendon allograft and semitendinosus autograft preparation.
Technical Alternatives and Pitfalls
There is considerable controversy in the literature regarding the use of a tibial inlay versus a transtibial tunnel technique for PCL reconstruction. The transtibial technique requires the graft to bend around the “killer turn” at the PCL footprint, which has led some to postulate that this may lead to thinning of the graft.15 The tibial inlay technique avoids this turn while also allowing the PCL graft to be placed in its anatomic position. Authors have reported good results for patients undergoing PCL reconstruction using either the tibial inlay or the transtibial tunnel technique.2,16,17,18 Biomechanical studies of single versus double bundle PCL reconstruction have shown that the double bundle technique more effectively reproduces intact knee kinematics and in situ forces at all flexion angles of the knee.6,10,11,12,13 Early clinical results of double bundle PCL reconstruction have shown to be improved over single bundle reconstructions.19,20,21 In light of this recent clinical and biomechanical evidence, the double bundle PCL reconstruction with transtibial tunnel technique has become our technique of choice.
When drilling the tibial tunnel, adequate visualization is mandatory. The posteromedial portal is helpful in this regard. Due to the risk of neurovascular structures, the guide pin insertion and tunnel drilling should be performed with the knee flexed to 90 degrees.22,23
For patients following both HTO and PCL reconstruction, supervised physical therapy should take place for 4 to 6 months postoperatively.
Rehabilitation Protocol for Biplanar Opening Wedge High Tibial Valgus Osteotomy
Following the biplanar osteotomy, a hinged knee brace should be applied. It should be precontoured to provide a

slight valgus moment in the anteroposterior plane. Patients should wear this brace locked in extension for all activities except physical therapy exercises and continuous passive motion (CPM) use for 4 weeks postoperatively. The weight bearing status is dependent on osteotomy fixation, but usually includes partial weight bearing with crutches. Patients should begin quad sets, straight leg raises, heel slides, and CPM use from 0- to 90-degree knee flexion over the first 4 weeks. At 4 weeks the brace may be unlocked for ambulation, and the patient may begin weight bearing as tolerated with crutches. The brace and crutches may be discontinued at 6 weeks if the patient has full extension, good quadriceps control with no extension lag on straight leg raise, and a nonantalgic gait pattern. Range of motion and gentle strengthening exercises continue, with more aggressive strengthening beginning at 3 months postoperatively.
Fig. 47-9. Location of femoral tunnels and graft fixation. (Modified from Petrie et al. Double bundle posterior cruciate ligament reconstruction technique: University of Pittsburgh approach. Operative Tech Sports Med. 1999;7:118–126. Copyright © 1999, WB Saunders Co.)
Rehab Protocol for Posterior Cruciate Ligament Reconstruction
Following PCL reconstruction, the brace is locked in full extension for 1 week. The patient may be weight bearing as tolerated with crutches. At 1 week postoperatively the brace is unlocked for passive range of motion, with care taken by the therapist to protect against posterior tibial sagging. Patients should be counseled on the placement of a pillow under the proximal posterior tibia at rest to prevent posterior sag. Quadricep sets and hamstring and calf stretching may be initiated. At 1 month the patient should have full extension and flexion to 60 degrees with good quadriceps control. At this stage the brace may be unlocked for controlled supervised gait training, and the patient may begin active squats and wall slides with supervision (0 degrees to 45 degrees) to promote anterior tibial translation.9 The brace may be discontinued at approximately 8 weeks. The complete protocol for rehabilitation in these patients is available in the article by Irrgang and Fitzgerald.24
Outcomes and Future Directions
For PCL reconstruction failures, it is essential to perform a thorough assessment, determine the etiology of failure, and formulate a preoperative plan for each patient. It is important to consider not only intra-articular causes of failure, but also the secondary knee restraints such as bone, articular cartilage, menisci, and collateral ligaments. The PCL revision reconstruction may be performed as part of a one- or two-stage procedure. General principles of management of failed PCL surgery therefore include the correction of bony malalignment, the treatment of any combined elements of instability, reconstruction and not repair of the PCL, and compliance with an adequate postoperative rehabilitation protocol. With attention to these details one can expect adequate clinical results in this challenging patient population, but these are challenging complex procedures with expected results inferior to those in the primary PCL reconstruction setting.
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19. Nyland J, Hester P, Caborn DN. Double-bundle posterior cruciate ligament reconstruction with allograft tissue: 2-year postoperative outcomes. Knee Surg Sports Traumatol Arthrosc. 2002;10(5): 274–279. (E-pub 2002 Jun 28.)
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21. Chen CH, Chen WJ, Shih CH. Arthroscopic double-bundled posterior cruciate ligament reconstruction with quadriceps tendon-patellar bone autograft. Arthroscopy. 2001;16:780–782.
22. Miller MD, Kline AJ, Gonzales J, et al. Vascular risk associated with a posterior approach for posterior cruciate ligament reconstruction using the tibial inlay technique. J Knee Surg. 2002;15(3): 137–140.
23. Matava MJ, Sethi NS, Totty WG. Proximity of the posterior cruciate ligament insertion to the popliteal artery as a function of the knee flexion angle: implications for posterior cruciate ligament reconstruction. Arthroscopy. 2000;16(8):796–804.
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