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abstract

Two-Stage Revision Anterior Cruciate Ligament ReconstructionBrandon J. Erickson, Md; GrEGory cvEtanovich, Md; khalid Waliullah, Md; MichaEl khair, Md; Patrick sMith, Md; BErnard Bach Jr, Md; sEth shErMan, Md

Anterior cruciate ligament (ACL) reconstruction is the gold stan-dard treatment option for young,

active patients with functional instability following an ACL tear. It is estimated that there are greater than 250,000 ACL tears

annually in the United States,1 more than half of which will undergo reconstruc-tion.2 This equates to an annual cost of approximately $1 billion for the health care industry.3 Despite good or excellent outcomes in the majority of patients, graft

rupture rates after reconstruction range from 5% to 25%, with the highest rates found in young athletes involved in cut-ting or pivoting sports and lower rates found in those who are jumpers or who pursue straight line activities.4-8 In addi-tion, a significant subset of patients have persistent or recurrent functional insta-bility following ACL reconstruction that limits their ability to return to sport, even without overt graft failure.

With the increase in the number of primary ACL reconstructions, the need for revision ACL reconstruction is also increasing.9 Some authors estimate the revision ACL reconstruction burden to

The number of primary anterior cruciate ligament (ACL) tears is rapidly increas-ing. In patients who wish to return to their preoperative level of function, specif-ically as it pertains to participation in sports, the gold standard of treatment fol-lowing an ACL tear remains an anterior cruciate ligament (ACL) reconstruction. Despite a majority of good/excellent results following primary ACL reconstruc-tion, there is a growing subset of patients with persistent or recurrent functional instability who require revision ACL reconstruction. Preoperative planning for revision ACL reconstruction requires a careful understanding of the root cause of ACL failure, including possible technical causes of primary ACL failure and the presence of combined knee pathology that was not addressed at the index ACL reconstruction. The decision to perform 2-stage revision ACL reconstruc-tion is multifactorial and is reached by technical considerations that may make a 1-stage revision less optimal, including tunnel widening, arthrofibrosis, active infection, and others. Concomitant knee pathology such as meniscal deficiency, malalignment (including an increase in posterior tibial slope), chondral lesions, and other ligamentous laxity may also require a staged approach to treatment. This evidence-based review covers the indications for 2-stage revision ACL re-construction, surgical techniques, evidence for and technique of bone grafting prior ACL tunnels, and outcomes of 2-stage revision stratified by initial cause of ACL reconstruction failure. With proper preoperative planning and an under-standing of the cause of failure following the primary ACL reconstruction, revi-sion ACL reconstruction can offer excellent outcomes in the motivated patient. [Orthopedics. 2016; 39(3):e456-e464.]

The authors are from the Department of Or-thopaedic Surgery (BJE, GC, MK, BB), Rush Uni-versity, Chicago, Illinois; and the Department of Orthopaedic Surgery (KW, PS, SS), Division of Sports Medicine, University of Missouri, Colum-bia, Missouri.

Drs Erickson, Cvetanovich, Bach, and Sher-man are previous Blue Ribbon Article Award re-cipients (Orthopedics, January/February 2016).

Drs Erickson, Cvetanovich, Waliullah, Khair, Smith, and Sherman have no relevant financial relationships to disclose. Dr Bach has received grants from Arthrex, ConMed, DJO, and Ossur.

Correspondence should be addressed to: Brandon J. Erickson, MD, Department of Ortho-paedic Surgery, Rush University, 1611 W Harri-son St, Chicago, IL 60612 (berickso.24@gmail.com).

Received: July 16, 2015; Accepted: October 4, 2015.

doi: 10.3928/01477447-20160324-01

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be 13,000 per year.9 Successful revision surgery requires an understanding of the root cause of failure, careful preopera-tive planning, meticulous surgical execu-tion, proper postoperative rehabilitation, and appropriate patient counseling. A relatively small but challenging subset of patients requires 2-stage revision ACL re-construction. Recognition of patients who may benefit from this treatment strategy is critical. Major reasons to proceed with a 2-stage strategy include tunnel widening or other loss of bone stock, arthrofibrosis, active infection, concomitant meniscal deficiency, malalignment, and focal chon-dral lesions and/or other ligamentous lax-ity that may require a staged approach.10,11

This article will provide an evidence-based review of 2-stage revision ACL re-construction. It will address the epidemiol-ogy of revision ACL reconstruction; root causes of primary ACL failure; evaluation and workup of a patient with a failed pri-mary ACL reconstruction; determination of 1-stage vs 2-stage revision reconstruction; and technical aspects of 2-stage reconstruc-tion, including evidence for and techniques of bone grafting ACL tunnels, outcomes of revision ACL reconstruction, and return-to-sport prognosis for these difficult cases.

EpidEmiology of REvision AntERioR CRuCiAtE ligAmEnt REConstRuCtion

In the United States, the incidence of ACL reconstruction has risen from 86,687

in 1994 to 129,836 in 2006, with 95% of these surgeries performed in an out-patient setting (compared with just 43% in 1994).12 The revision rate for primary ACL reconstruction varies from 1.5% to almost 10% depending on surgeon expe-rience and patient age, among other fac-tors.13-16 The revision rate often peaks between 1 to 2 years after the primary ACL reconstruction, likely secondary to return to sport,17 and the outcomes after revision surgery are generally inferior to those after primary ACL reconstruc-tion.17,18 The rerupture rate after a revision ACL reconstruction is highly variable and has been reported to be between 3.5% to 33% in the hands of an experienced sur-geon.9,17,18 Patients who received allograft tissue at the time of their revision surgery are at an even higher risk for failure.13,17-23 In addition to rerupture, patients with re-vision ACL reconstruction have inferior outcomes in functional scores, quality of life, strength, and other outcome measures compared with primary ACL reconstruc-tion.12,17,18,24 This must be conveyed to the patient preoperatively to set realistic expectations for the postoperative course.

To the current authors’ knowledge, there is no report on the total number of 1-stage vs 2-stage revision ACL recon-

structions. However, there are signifi-cantly more reports on the outcomes of 1-stage revision ACL reconstruction than 2-stage approaches.

Root CAusEs of pRimARy AntERioR CRuCiAtE ligAmEnt fAiluRE

Failure of primary ACL reconstruc-tion is often multifactorial. Graft failure can be divided into traumatic and atrau-matic. Traumatic etiologies account for approximately 25% of graft failures.25 Patients who sustain a traumatic failure often return to high levels of activity prior to achieving appropriate neuromuscular control.13 In general, this cohort reports progressing well in the postoperative re-habilitation period prior to a recurrent traumatic pivoting event. Radiographs of-ten show properly aligned tunnels (Figure 1).

Atraumatic causes of graft failure, en-compassing 75% of failures, occur when the patient notes a feeling of recurrent in-stability in the knee without a history of a new traumatic event.25 Although there are many potential causes of atraumatic failure, technical errors, specifically tun-nel malposition, are cited as the most common cause of atraumatic graft failure after ACL reconstruction.25 Although a

Figure 1: Anteroposterior (A) and lateral (B) radio-graphs of a knee after anterior cruciate ligament reconstruction demonstrating ideal placement of tibial and femoral tunnels.

BA

Figure 2: Lateral radiograph of a knee after anterior cruciate ligament reconstruction demonstrating an an-teriorly placed femoral tunnel (A). Anteroposterior (B) and lateral (C) radiographs of a knee after anterior cruciate ligament reconstruction demonstrating a vertically oriented femoral tunnel.

A B C

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malpositioned femoral tunnel, typically placed too anterior (Figure 2A) or verti-cal (Figures 2B-C), is a common error in tunnel position, the tibial tunnel can also be placed erroneously and can contribute to graft failure (Figure 3).26,27 When a tunnel is malpositioned, the graft under-goes plastic deformation with only small changes in length. If either the tibial or femoral tunnel is placed such that the graft lengthens to achieve full range of motion (ROM), the graft will elongate and lose its tension. As an example, if the femoral tun-nel is too anterior, the graft will be tight in flexion and will stretch out with repeated knee motion, leading to instability and a pathologic pivot shift.27

A second cause of atraumatic graft failure is failure of the graft to incorporate and undergo proper ligamentization.14,28 This can occur due to poor initial graft choice, lack of vascularity, the patient’s immunologic response, aggressive reha-bilitation, or impingement.21,28 Insuffi-cient fixation of the graft can also lead to failure. The stability of the graft at time zero is completely dependent on the fixa-tion method, and if the fixation achieved at the time of surgery is inadequate, the graft may fail.

Loss of motion in either knee flexion or extension can compromise a patient’s outcome after ACL reconstruction and lead to atraumatic failure.13 A loss of only 5° of extension or 15° of flexion can compromise a patient’s ability to func-tion properly and necessitate a revision procedure.29 This slight loss of extension can cause the patient to walk with a bent-knee gait, resulting in quadriceps fatigue, dysfunction, and weakness as well as an-terior knee pain.14 Loss of motion can be secondary to technical errors in graft/tun-nel placement, improper rehabilitation in the postoperative setting, arthrofibrosis, infection, or pain syndromes that result in a patient’s refusal to move the knee.11,23,30 Notch or posterior cruciate ligament im-pingement of the graft from nonanatomic

position or from scar adjacent to the notch (ie, cyclops lesion) can cause loss of mo-tion and/or lead to a graft failure over time (Figure 4).30,31 Patients who experience a loss of motion following ACL reconstruc-tion are at a higher risk of developing ar-thritis.32

Meniscal deficiency can also be a sig-nificant cause of a primary ACL failure given the multifaceted role the meniscus plays in knee stability, as well as lubrica-tion and proprioception.27 It is well es-tablished that the medial meniscus uses the breakstop mechanism and acts as an important secondary stabilizer to ante-rior tibial translation.33,34 In the medial meniscus–deficient state, the ACL graft experiences significantly more stress and is therefore more likely to fail.13,33 There is also growing evidence to suggest that the lateral meniscus may play a stabilizing role in tibial internal rotation and in help-ing to modulate the pivot shift.35

Malalignment is also an important fac-tor regarding ACL failure. Extremes of coronal malalignment (ie, varus, valgus) may lead to failure through excessive graft forces or by accentuating laxity in extra-articular secondary stabilizing ligaments (ie, medial collateral ligament, postero-lateral corner). In addition, recent studies have shown that increased posterior tibial slope is also a risk factor for failure of ACL reconstruction.36,37 In patients with in-creased tibial slope, there is increased an-terior translational force that can increase strain.38,39 Recognizing and addressing these risk factors for ACL failure is critical to successful revision ACL surgery.

EvAluAtion And WoRkup of A pAtiEnt With A fAilEd AntERioR CRuCiAtE ligAmEnt REConstRuCtion History

Evaluation of the patient begins with a thorough history, making sure to clarify the inciting event that caused the initial ACL tear, as well as the clinical course following primary ACL reconstruction. The timing and symptoms associated with

Figure 3: Lateral radiograph of a knee after anterior cru-ciate ligament reconstruction demonstrating the initial posteriorized tibial tunnel (red arrow) and the subse-quent revision anterior cruciate ligament reconstruc-tion with a properly placed tibial tunnel (blue arrow) (A). Arthroscopic image of a knee that has previously undergone an anterior cruciate ligament reconstruction demonstrating a posteriorly placed tibial tunnel (B).

B

A

Figure 4: Arthroscopic image of an intercondylar notch that did not undergo a notchplasty prior to anterior cruciate ligament reconstruction.

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failure of the primary ACL reconstruc-tion should be elucidated to determine the type and cause of failure. Failures within 6 months are more likely to be caused by technical errors or early return to sport prior to regaining appropriate neuromus-cular control.40 Insidious onset of recur-rent knee laxity may be due to technical errors or failure of graft incorporation. Lack of motion in the early postoperative period may be representative of arthrofi-brosis. Patients with fevers, chills, inabil-ity to bear weight, or significant painful motion should be evaluated closely to rule out infection. Failures after 1 to 2 years are typically traumatic and often occur in the setting of a previously well-function-ing knee. Atraumatic late failures may be secondary to concomitant knee pathology, including meniscal deficiency, malalign-ment, chondral lesions, or other missed ligamentous injury.

Every effort should be made to ob-tain previous operative reports. Techni-cal issues such as tunnel size, technique of drilling, graft choice, fixation, and any concomitant procedures should be taken into consideration. This will aid in deter-mining causes of failure and planning a revision ACL reconstruction.

Physical ExaminationAs with any other knee examination,

the physical examination should start with inspection, palpation, passive ROM, ac-tive ROM, strength testing of the entire leg, and special tests. Prone heel height should be measured by comparison with the uninjured side. A loss of 1 cm of heel height equates to roughly 1° loss of ex-tension. Loss of extension compared with the contralateral side can lead to a bent-knee gait pattern with anterior knee pain and quadriceps muscle weakness.11 This is often more problematic than loss of flexion. The ACL can be evaluated us-ing the anterior drawer, Lachman, and pivot shift tests.41 The Lachman test is the most sensitive test in evaluating the ACL, whereas the pivot shift test, particularly

when performed under anesthesia, is the most specific.42 The posterior cruciate lig-ament can be evaluated with the posterior drawer and sag sign, and posteromedial and posterolateral corner pathology can be determined by varus/valgus and ro-tational stress testing in both supine and prone position. Failure to recognize and address deficiencies in the knee second-ary stabilizers at the time of revision ACL reconstruction increases the risk of recur-rent ACL reconstruction failure.

Imaging StudiesImaging studies for the patient present-

ing with a clinical failed ACL reconstruc-tion begin with radiographs, including an-teroposterior (AP), Rosenberg (45° flexion posteroanterior), lateral, Merchant, and, in select cases, full-length mechanical axis views. These should be used to determine the position of any hardware and previous femoral and tibial tunnels, the presence of joint-space narrowing, overall limb align-ment, and any concomitant pathology (ie, Segond fracture, Pellegrini-Stieda lesion). Tunnel position should be critically as-sessed on true AP and lateral views, and tunnel widening should be ruled out, typi-cally best seen using the AP view for the femoral tunnel and lateral view for the tibial tunnel.13,43

Once radiographs have been complet-ed, advanced imaging may be warranted. This includes magnetic resonance imag-ing (MRI), as well as computed tomog-raphy (CT) if there is concern for tunnel widening. If there is a traumatic injury, MRI may demonstrate the characteristic pattern of bone edema in the posterior aspect of the lateral tibial plateau and an-terolateral femoral condyle.44 Magnetic resonance imaging can also allow assess-ment of tunnel position and estimation of the cross-sectional area of the tunnels to look for femoral and tibial tunnel widen-ing.45,46

The current gold standard for evaluat-ing tunnel widening is CT because stud-ies have shown that CT outperforms MRI and radiographs in both inter- and intrao-bserver reliability for evaluating tunnel widening.47-49 The authors favor a selective approach to ordering CT scans to evaluate tunnel position and widening. The decision to order a CT scan in addition to the radio-graphs and MRI is based on the quality of the MRI and the surgeon’s comfort with using MRI to evaluate tunnel position and widening. Assessment of tunnel position and widening is crucial because this can help dictate whether the patient will un-dergo a 1- or 2-stage revision ACL recon-struction. Radiographs (Figures 5A-B), as

Figure 5: Anteroposterior (A) and lateral (B) radiographs of a knee demonstrating widening of the tibial tunnel in the setting of a failed anterior cruciate ligament reconstruction. Sagittal magnetic resonance imaging demonstrating widening of the tibial tunnel in the setting of a failed anterior cruciate ligament reconstruction (C).

CBA

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well as MRI (Figure 5C) or CT axial cuts, will allow the surgeon to measure the tun-nel width in both the femur and tibia. There remains no absolute value regarding tunnel dimensions that can be grafted in a single stage; however, the authors recommend a 2-stage procedure be performed when tun-nel widening greater than 10 to 15 mm is present.13,50,51

dEtERminAnts of 1-stAgE vERsus 2-stAgE AntERioR CRuCiAtE ligAmEnt REConstRuCtion

Patients who have properly positioned tunnels, good bone stock, and hardware that can be removed or will not interfere with graft fixation should be considered for a 1-stage revision ACL reconstruction. If the original tunnels are far enough off from the ideal position (ie, vertical graft) that the tunnel and fixation will not in-terfere with anatomic tunnel placement, a 1-stage revision can also be performed while leaving the existing hardware in place. If the original tunnels are in the proper position but there is a significant amount of widening present either before or after removal of the hardware, these pa-tients may be better served by a 2-staged approach.13,51,52 An absolute threshold for how much tunnel widening and bone loss is acceptable to undergo a single stage with intraoperative bone grafting prior to drilling has not been established. Based on the available evidence, the current authors recommend a 2-stage procedure, with bone grafting at the first stage when there is more than 10 to 15 mm of tunnel widening.13,50,51 If there is minimal wid-ening, an intraoperative decision can be made regarding a 1- vs 2-stage revision. In this case of borderline widening (ie, 3-5 mm), 2 interference screws can be stacked to provide adequate aperture fixation, tun-nel trajectory can be altered by different femoral drilling techniques (eg, antero-medial portal, outside-in), or a larger graft such as a quadriceps autograft may be used with aperture or suspensory fixation to fill the void of the widened tunnel.53

Meniscal status, alignment, other liga-ment status, and presence of high-grade chondral lesions affect decision making for a 1- vs 2-stage revision ACL reconstruc-tion. In an otherwise well-aligned knee where the meniscal, chondral, and other ligament status is clearly defined preopera-tively, 1-stage ACL reconstruction may be performed alongside other ligament stabi-lization, meniscal allograft transplantation, and/or cartilage restoration. If the menis-cal, chondral, or other ligament status is unclear or unknown, consideration should be made for a staging diagnostic arthrosco-py and planned 2-stage revision approach. Similarly, if the knee is malaligned and the meniscal/chondral/ligamentous status is well known, a 1-stage approach, including realignment osteotomy, revision ACL re-construction, and other concomitant intra-articular procedures, can be considered.

In the malaligned knee, if it is unclear whether there is ACL tunnel widening, meniscal deficiency, other ligament injury, and/or high-grade cartilage lesion, a 2-stage approach should be considered. During the first stage, arthroscopy should be performed with intra-articular synovectomy/lysis of adhesions, evaluation of ACL tunnels with removal of hardware and possible bone grafting, evaluation of ligament and menis-cal status, and determination of size and location of cartilage lesions. Following ar-throscopy, extra-articular procedures such as realignment osteotomy plus possible other ligament stabilization (eg, postero-medial/posterolateral corner reconstruc-tion) should be performed during the first stage. Once the bone heals and the patient regains full ROM, the second stage should be performed, including revision ACL re-construction and addressing other intra- articular pathology with meniscal allograft transplantation and/or cartilage procedure as indicated.

Other indications for 2-stage revision ACL reconstruction include arthrofibrosis or active infection. In the setting of ar-throfibrosis, the remnant ACL should be evaluated and debrided in its entirety pro-

vided it is not synthetic. If it is synthetic, it should be removed whole to avoid cre-ating an inflammatory response, although some authors still remove this graft with a shaver.54 Excessive debridement of the fat pad is avoided to minimize the risk of postoperative hemoarthrosis and further development of arthrofibrosis. The pa-tient may also need manipulation under anesthesia at the time of the first stage, and performing a revision ACL recon-struction at the same time is not recom-mended.20,51 Bone grafting can also be done during the arthrofibrosis procedure. The patient should be started in an aggres-sive rehabilitation program to attempt to regain as much ROM as possible prior to revision ACL reconstruction. If a patient has an active infection with failed ACL re-construction, new hardware should not be implanted, and revision ACL reconstruc-tion would involve 2 stages, with initial washout, debridement, synovectomy, and antibiotics to fully eradicate the infection followed by the second stage of revision ACL reconstruction once the infection has been eradicated.

suRgiCAl ConsidERAtions duRing 2-stAgE REConstRuCtion Tunnel Bone Grafting

To perform tunnel bone grafting, first remove any hardware that could interfere with future tunnel placement and check each tunnel to ensure there are no corti-cal breaches. Most screws can be removed with a 3.5-mm screwdriver, but operative reports should be obtained to determine the specific type of screw used in prior procedures so the appropriate equipment can be in the operating room. Screw re-moval can be difficult, and all soft tissue and bone over the screw heads should be removed to allow the screwdriver to seat properly on the screw to prevent strip-ping. A nitinol pin is placed in the screw to facilitate screwdriver seating. Screws that are stripped often need to be removed with broken screw–removal kits. Bioab-sorbable screws are typically not resorbed

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at the time of revision ACL reconstruc-tion and should be removed with care if present because they can break during re-moval. Because metal cross-links can be extremely difficult to remove, the authors recommend overdrilling these and remov-ing the entire wedge of bone. Although this creates a somewhat larger defect, the authors’ experience is that this is typically the most effective way to address this situ-ation. The defect will be filled with graft later in the procedure.

Once the hardware has been removed, debride the widened tunnels of any soft tissue and sclerotic bone using a shaver, burr, drill, rasp, and curette. The surgeon should attempt to preserve as much native bone as possible. Bone graft is then im-pacted into each tunnel. Once the tunnels are prepped, the bone graft is inserted. This can be either autograft taken from the tibia or iliac crest, allograft, or synthetic graft (Table). If autograft is used, the bone is harvested as dowels and impacted into the tunnels. For allograft, a single bone dowel is used that is approximately 1 mm larger than the diameter of the tunnel and placed using a bone tamp for a press-fit technique, ensuring the entire tunnel is filled. The sterilization technique, risks, and cost information for these dowels has been previously described (Figure 6).19 Another option for bone grafting the femoral tunnel is to use morselized bone graft, delivered via an enlarged anterome-dial arthroscopic portal directly into the bone defect. The authors have found that a 3-mL syringe with the tip cut off or a shoulder arthroscopy cannula can facili-tate delivery of graft to the defect while reducing extravasation into the rest of the joint. The tibial tunnel should be packed from outside the joint, with care taken to avoid breaching the joint with the bone graft. The joint is then checked thorough-ly to ensure there are no free pieces of graft loose within the knee.

Following bone grafting, the patient should be followed clinically with repeat radiographs and CT approximately 3 to 4

months after the first stage to ensure the bone tunnels have fully consolidated. If the tunnels have not completely incorpo-rated, the patient may need to wait an ad-ditional 2 to 3 months before definitive re-vision ACL reconstruction may be safely performed.

Revision Anterior Cruciate Ligament Graft Choice

The ideal graft choice for all revision ACL reconstruction procedures has yet to be elucidated and will often depend on graft used during the primary ACL reconstruction. Studies have shown both significantly lower rerupture rates as well as significantly better outcomes in sev-

eral validated knee outcome measures in patients undergoing revision ACL recon-struction with autograft compared with allograft.21,30 The risk of graft rerupture following revision ACL reconstruction in patients receiving autograft is 2.78 times less likely than in those receiving allograft.21 For these reasons, the authors prefer using autograft for revision ACL reconstruction when possible.21 If the in-dex procedure was an allograft or ham-string autograft, consideration is made for revision with ipsilateral bone-tendon-bone autograft. When bone-tendon-bone autograft is not available or when tech-nical considerations may make large-diameter soft tissue graft more desirable,

Table

Bone Graft Options in Revision Anterior Cruciate Ligament Reconstruction

Bone Graft Benefits Negatives

Iliac crest autograft Structural graft,a signifi-cant volume available

Donor-site morbidity

Anterior tibial plateau autograft

Available through same incision,b local

Technically difficult to avoid desired tibial tun-nel trajectory, limited quantity

Gerdy’s tubercle autograft Available locally Limited quantity

Crushed cancellous allograft No donor-site morbidity, large quantity

Osteoconductive only, high cost

aDowels can be harvested to impact for large defects. bIf transpatellar portal is used.

Figure 6: Arthroscopic images of a debrided femoral tunnel as the bone dowel is positioned for insertion (A) and during insertion of the dowel of allograft bone (B).

BA

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consideration is made for quadriceps ten-don autograft. This viable graft choice has demonstrated good outcomes, with a re-ported return-to-sport rate of greater than 90% following revision ACL reconstruc-tion with quadriceps tendon autograft.55-57 For the quadriceps autograft, this can be taken with or without bone block, depend-ing on surgeon preference and the need to fill any residual bone voids at the tunnel aperture. In some cases, graft preparation for 2-stage revision ACL reconstruction should be delayed until the bone graft tun-nels have been assessed, to allow variation in bone plug size if needed. Rarely, the au-thors consider contralateral bone-tendon-bone autograft, ipsilateral or contralateral hamstring autograft, or allograft as a graft choice in certain situations (eg, ACL re-revision).

Miscellaneous Technical PearlsSurgeons need to be prepared with

multiple strategies for tunnel preparation and graft fixation in the revision setting. Surgeons should have a low threshold for supplemental fixation on the femoral and especially the tibial side due to weak bone from bone-grafted tunnels or enlarged tunnels. In addition, consideration should be made for alternative femoral and tibial drilling techniques, including outside-in or anteromedial portal techniques, to vary the trajectory of the tunnel from a previ-ously drilled tunnel as necessary. Famil-iarity with and use of all-inside femoral and tibial sockets with cortical suspensory fixation may be necessary when aperture fixation is not possible or desirable. Final-ly, in revision ACL surgery, arthroscopic landmarks are often difficult to identify; therefore, intraoperative fluoroscopy can be used to assist in identifying tunnel po-sition before drilling.

suRgiCAl outComEs of 2-stAgE AntERioR CRuCiAtE ligAmEnt REConstRuCtion

It is an accepted fact that outcomes from revision ACL reconstruction are

inferior to those from primary ACL re-construction. Carson et al11 reported 43 patients who underwent a 1-stage revision ACL reconstruction, 93% of whom had a concomitant procedure at the time of revi-sion ACL reconstruction. They found that at 2 years postoperatively, 86% had a neg-ative pivot shift and a grade 0 or 1 Lach-man, 63% had good or excellent results on the Hospital for Special Surgery (HSS) knee rating system, and 74% returned to athletic activity at the preoperative level or with some limitations.11 Diamantopou-los et al25 reviewed 107 revision ACLRs, 6 of which were 2-stage procedures. At 73 months, a significant improvement in Lysholm (88.5±12.4 vs 51.5±24.9; P<.001) and Tegner scores (6.3±1.8 vs 2.8±1.8; P<.001) was seen, but most pa-tients did not achieve their preinjury ac-tivity level.25 The authors did not stratify their results by whether the patient under-went a 1- or 2-stage procedure.

There are fewer studies reporting the outcomes of 2-stage revision ACL recon-struction alone. Franceschi et al58 evalu-ated 30 patients who underwent 2-stage revision ACL reconstruction after a trau-matic rerupture of their ACL. All patients in the study underwent hardware removal and filling of the tunnels (which measured, on average, 10.4 mm in diameter and 26.4 mm in length) with autograft harvested from the tibial metaphysis. The second stage of the revision ACL reconstruction was performed a minimum of 3 months later, after obtaining CT demonstrating adequate fill of the tunnels using ham-string autograft through a transtibial drill-ing technique. At 5 years postoperatively, 86.7% of patients had full extension, 90% had less than a 5° difference in flexion compared with the contralateral knee, 66.7% returned to preinjury sport activity level, and there was a significant improve-ment in Lysholm score when comparing pre- and postoperative values.58

Thomas et al52 reported the results of 49 consecutive 2-stage revision ACL re-constructions in which the hardware was

removed and the tibial tunnel grafted dur-ing the first stage, followed by an ACL reconstruction using various grafts and fixation methods for the second stage. This group was then compared with a group of patients who underwent a pri-mary ACL reconstruction. The 2-stage group contained significantly more pa-tients with meniscal and chondral pathol-ogy compared with the primary ACL re-construction group. At a mean follow-up of 6 years, there was an improvement in International Knee Documentation Com-mittee scores for both groups, with higher scores seen in the primary ACL recon-struction group. However, the objective laxity measurements of the graft were not significantly different between groups.52 The authors had a subset of 8 patients who received 1-stage revision ACL reconstruc-tion, but data from these patients were not included in this study.

REtuRn to ACtivity AftER 2-stAgE REvision AntERioR CRuCiAtE ligAmEnt REConstRuCtion

Several studies have confirmed the success of returning athletes, both rec-reational and elite, to sport after primary ACL reconstruction.59-64 However, revi-sion ACL reconstruction is a different sce-nario for the patient and physician. The patient must understand going in to the procedure that revision ACL reconstruc-tion is a salvage operation, with the goal of obtaining a functional stable knee for activities of daily living. The return-to-sport rate is lower than in primary ACL reconstruction, with studies citing a 62% to 74% rate of return to sport in revision ACL reconstruction, with high school and college athletes achieving a higher return-to-sport rate (74%) than recreational ath-letes (62%).64 Patients must understand their time to return to sport may be longer after revision ACL reconstruction and will depend on their ability to regain symmet-ric strength compared with the contralat-eral leg and to complete a series of sport-specific tests. The physician must ensure

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the patient has a proper understanding of this to avoid a feeling of failure if return to sport is not obtained, despite obtaining a stable knee and improved quality of life.

ConClusionFailure of primary ACL reconstruc-

tion presents a unique set of challenges, including technical considerations and concomitant knee pathology that must be addressed at the time of revision surgery. Two-stage revision ACL reconstruction should be considered in cases of ACL tun-nel widening, arthrofibrosis, or infection, or in cases with concomitant knee ma-lalignment, meniscal deficiency, chondral lesions, and/or other ligament instability. Two-stage revision ACL reconstruction carries a more guarded prognosis than primary ACL reconstruction. However, careful preoperative planning, meticu-lous surgical technique, patient-specific postoperative rehabilitation, and realis-tic patient expectations may increase the chance of a good result in this challenging patient population.

REfEREnCEs 1. Marrale J, Morrissey MC, Haddad FS. A

literature review of autograft and allograft anterior cruciate ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2007; 15(6):690-704.

2. Frank CB, Jackson DW. The science of re-construction of the anterior cruciate ligament. J Bone Joint Surg Am. 1997; 79(10):1556-1576.

3. Griffin LY, Agel J, Albohm MJ, et al. Non-contact anterior cruciate ligament injuries: risk factors and prevention strategies. J Am Acad Orthop Surg. 2000; 8(3):141-150.

4. George MS, Dunn WR, Spindler KP. Current concepts review: revision anterior cruciate ligament reconstruction. Am J Sports Med. 2006; 34(12):2026-2037.

5. Mehta VM, Mandala C, Foster D, Petsche TS. Comparison of revision rates in bone-patella tendon-bone autograft and allograft anterior cruciate ligament reconstruction. Orthopedics. 2010; 33(1):12.

6. Hettrich CM, Dunn WR, Reinke EK, MOON Group, Spindler KP. The rate of subsequent surgery and predictors after anterior cruci-ate ligament reconstruction: two- and 6-year follow-up results from a multicenter cohort. Am J Sports Med. 2013; 41(7):1534-1540.

7. Leiter JR, Gourlay R, McRae S, de Korom-pay N, Macdonald PB. Long-term follow-up of ACL reconstruction with hamstring auto-graft. Knee Surg Sports Traumatol Arthrosc. 2014; 22(5):1061-1069.

8. Wright RW, Magnussen RA, Dunn WR, Spindler KP. Ipsilateral graft and contralater-al ACL rupture at five years or more follow-ing ACL reconstruction: a systematic review. J Bone Joint Surg Am. 2011; 93(12):1159-1165.

9. Leroux T, Wasserstein D, Dwyer T, et al. The epidemiology of revision anterior cruciate ligament reconstruction in Ontario, Canada. Am J Sports Med. 2014; 42(11):2666-2672.

10. Andernord D, Desai N, Bjornsson H, Ylander M, Karlsson J, Samuelsson K. Pa-tient predictors of early revision surgery after anterior cruciate ligament reconstruc-tion: a cohort study of 16,930 patients with 2-year follow-up. Am J Sports Med. 2015; 43(1):121-127.

11. Carson EW, Anisko EM, Restrepo C, Panari-ello RA, O’Brien SJ, Warren RF. Revision anterior cruciate ligament reconstruction: eti-ology of failures and clinical results. J Knee Surg. 2004; 17(3):127-132.

12. Mall NA, Chalmers PN, Moric M, et al. In-cidence and trends of anterior cruciate liga-ment reconstruction in the United States. Am J Sports Med. 2014; 42(10):2363-2370.

13. Allen CR, Giffin JR, Harner CD. Revision anterior cruciate ligament reconstruction. Orthop Clin North Am. 2003; 34(1):79-98.

14. Brown CH Jr, Carson EW. Revision anterior cruciate ligament surgery. Clin Sports Med. 1999; 18(1):109-171.

15. Chahal J, Lee A, Heard W, Bach BR Jr. A retrospective review of anterior cruciate liga-ment reconstruction using patellar tendon: 25 years of experience. Orthop J Sports Med. 2013; 1(3):2325967113501789.

16. Kvist J, Kartus J, Karlsson J, Forssblad M. Results from the Swedish National Anterior Cruciate Ligament Register. Arthroscopy. 2014; 30(7):803-810.

17. Lind M, Menhert F, Pedersen AB. Incidence and outcome after revision anterior cruciate ligament reconstruction: results from the Danish registry for knee ligament reconstruc-tions. Am J Sports Med. 2012; 40(7):1551-1557.

18. Lind M, Lund B, Fauno P, Said S, Miller LL, Christiansen SE. Medium to long-term follow-up after ACL revision. Knee Surg Sports Traumatol Arthrosc. 2012; 20(1):166-172.

19. Battaglia TC, Miller MD. Management of bony deficiency in revision anterior cruciate ligament reconstruction using allograft bone dowels: surgical technique. Arthroscopy. 2005; 21(6):767.

20. Getelman MH, Friedman MJ. Revision ante-

rior cruciate ligament reconstruction surgery. J Am Acad Orthop Surg. 1999; 7(3):189-198.

21. MARS Group. Effect of graft choice on the outcome of revision anterior cruciate liga-ment reconstruction in the Multicenter ACL Revision Study (MARS) cohort. Am J Sports Med. 2014; 42(10):2301-2310.

22. Nelson IR, Chen J, Love R, Davis BR, Ma-letis GB, Funahashi TT. A comparison of revision and rerupture rates of ACL recon-struction between autografts and allografts in the skeletally immature. Knee Surg Sports Traumatol Arthrosc. 2016; 24(3):773-779.

23. Noyes FR, Barber-Westin SD. Revision an-terior cruciate ligament surgery: experience from Cincinnati. Clin Orthop Relat Res. 1996; 325:116-129.

24. Johnson DL, Swenson TM, Irrgang JJ, Fu FH, Harner CD. Revision anterior cruciate liga-ment surgery: experience from Pittsburgh. Clin Orthop Relat Res. 1996; 325:100-109.

25. Diamantopoulos AP, Lorbach O, Paessler HH. Anterior cruciate ligament revision re-construction: results in 107 patients. Am J Sports Med. 2008; 36(5):851-860.

26. Muneta T, Yamamoto H, Ishibashi T, Asahina S, Murakami S, Furuya K. The effects of tibial tunnel placement and roofplasty on re-constructed anterior cruciate ligament knees. Arthroscopy. 1995; 11(1):57-62.

27. Trojani C, Sbihi A, Djian P, et al. Causes for failure of ACL reconstruction and influence of meniscectomies after revision. Knee Surg Sports Traumatol Arthrosc. 2011; 19(2):196-201.

28. Carlisle JC, Parker RD, Matava MJ. Techni-cal considerations in revision anterior cru-ciate ligament surgery. J Knee Surg. 2007; 20(4):312-322.

29. Nwachukwu BU, McFeely ED, Nasreddine A, et al. Arthrofibrosis after anterior cruciate ligament reconstruction in children and ado-lescents. J Pediatr Orthop. 2011; 31(8):811-817.

30. MARS Group, Wright RW, Huston LJ, et al. Descriptive epidemiology of the Multicenter ACL Revision Study (MARS) cohort. Am J Sports Med. 2010; 38(10):1979-1986.

31. Zantop T, Diermann N, Schumacher T, Schanz S, Fu FH, Petersen W. Anatomi-cal and nonanatomical double-bundle an-terior cruciate ligament reconstruction: importance of femoral tunnel location on knee kinematics. Am J Sports Med. 2008; 36(4):678-685.

32. Shelbourne KD, Urch SE, Gray T, Freeman H. Loss of normal knee motion after anterior cruciate ligament reconstruction is associat-ed with radiographic arthritic changes after surgery. Am J Sports Med. 2012; 40(1):108-113.

33. Chen JL, Allen CR, Stephens TE, et al. Dif-ferences in mechanisms of failure, intraop-

e463

Copyright © SLACK inCorporAted

n Feature Article

erative findings, and surgical characteristics between single- and multiple-revision ACL reconstructions: a MARS cohort study. Am J Sports Med. 2013; 41(7):1571-1578.

34. Westermann RW, Wright RW, Spindler KP, Huston LJ, MOON Knee Group, Wolf BR. Meniscal repair with concurrent anterior cruciate ligament reconstruction: operative success and patient outcomes at 6-year follow-up. Am J Sports Med. 2014; 42(9):2184-2192.

35. Lane CG, Warren R, Pearle AD. The piv-ot shift. J Am Acad Orthop Surg. 2008; 16(12):679-688.

36. Li Y, Hong L, Feng H, Wang Q, Zhang H, Song G. Are failures of anterior cruciate liga-ment reconstruction associated with steep posterior tibial slopes? A case control study. Chin Med J (Engl). 2014; 127(14):2649-2653.

37. Sonnery-Cottet B, Mogos S, Thaunat M, et al. Proximal tibial anterior closing wedge osteotomy in repeat revision of anterior cru-ciate ligament reconstruction. Am J Sports Med. 2014; 42(8):1873-1880.

38. Marouane H, Shirazi-Adl A, Adouni M, Hashemi J. Steeper posterior tibial slope markedly increases ACL force in both active gait and passive knee joint under compres-sion. J Biomech. 2014; 47(6):1353-1359.

39. Webb JM, Salmon LJ, Leclerc E, Pinczewski LA, Roe JP. Posterior tibial slope and fur-ther anterior cruciate ligament injuries in the anterior cruciate ligament-reconstructed pa-tient. Am J Sports Med. 2013; 41(12):2800-2804.

40. Dunn WR, Spindler KP, MOON Consortium. Predictors of activity level 2 years after ante-rior cruciate ligament reconstruction (ACLR): a Multicenter Orthopaedic Outcomes Network (MOON) ACLR cohort study. Am J Sports Med. 2010; 38(10):2040-2050.

41. Dodd M, Trompeter A, Harrison T, Palmer S. The pivot shift test is of limited clinical relevance in the arthritic anterior cruciate ligament-deficient knee. J Knee Surg. 2010; 23(3):131-135.

42. van Eck CF, van den Bekerom MP, Fu FH, Poolman RW, Kerkhoffs GM. Methods to diagnose acute anterior cruciate ligament rupture: a meta-analysis of physical exami-nations with and without anaesthesia. Knee Surg Sports Traumatol Arthrosc. 2013; 21(8):1895-1903.

43. Scott WN. Insall & Scott Surgery of the Knee. 5th ed. New York, NY: Elsevier Churchill Livingstone; 2012.

44. Zeiss J, Paley K, Murray K, Saddemi SR. Comparison of bone contusion seen by MRI in partial and complete tears of the anterior cruciate ligament. J Comput Assist Tomogr. 1995; 19(5):773-776.

45. Fules PJ, Madhav RT, Goddard RK, New-man-Sanders A, Mowbray MA. Evaluation of tibial bone tunnel enlargement using MRI scan cross-sectional area measurement after autologous hamstring tendon ACL replace-ment. Knee. 2003; 10(1):87-91.

46. Siebold R. Observations on bone tunnel en-largement after double-bundle anterior cru-ciate ligament reconstruction. Arthroscopy. 2007; 23(3):291-298.

47. Groves C, Chandramohan M, Chew C, Sub-edi N. Use of CT in the management of an-terior cruciate ligament revision surgery. Clin Radiol. 2013; 68(10):e552-e559.

48. Hoser C, Tecklenburg K, Kuenzel KH, Fink C. Postoperative evaluation of femoral tun-nel position in ACL reconstruction: plain radiography versus computed tomography. Knee Surg Sports Traumatol Arthrosc. 2005; 13(4):256-262.

49. Marchant MH Jr, Willimon SC, Vinson E, Pietrobon R, Garrett WE, Higgins LD. Com-parison of plain radiography, computed to-mography, and magnetic resonance imaging in the evaluation of bone tunnel widening af-ter anterior cruciate ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2010; 18(8):1059-1064.

50. Azar FM. Revision anterior cruciate liga-ment reconstruction. Instr Course Lect. 2002; 51:335-342.

51. Harner CD, Giffin JR, Dunteman RC, An-nunziata CC, Friedman MJ. Evaluation and treatment of recurrent instability after ante-rior cruciate ligament reconstruction. Instr Course Lect. 2001; 50:463-474.

52. Thomas NP, Kankate R, Wandless F, Pandit H. Revision anterior cruciate ligament recon-struction using a 2-stage technique with bone grafting of the tibial tunnel. Am J Sports Med. 2005; 33(11):1701-1709.

53. Noyes FR, Barber-Westin SD. Revision an-terior cruciate surgery with use of bone-pa-tellar tendon-bone autogenous grafts. J Bone Joint Surg Am. 2001; 83(8):1131-1143.

54. Ventura A, Legnani C, Terzaghi C, Borgo E, Albisetti W. Revision surgery after failed ACL reconstruction with artificial ligaments: clinical, histologic and radiographic evalu-ation. Eur J Orthop Surg Traumatol. 2014; 24(1):93-98.

55. Ferretti A, Monaco E, Caperna L, Palma T, Conteduca F. Revision ACL reconstruction us-ing contralateral hamstrings. Knee Surg Sports Traumatol Arthrosc. 2013; 21(3):690-695.

56. Garofalo R, Djahangiri A, Siegrist O. Revi-sion anterior cruciate ligament reconstruc-tion with quadriceps tendon-patellar bone autograft. Arthroscopy. 2006; 22(2):205-214.

57. Shelbourne KD, O’Shea JJ. Revision ante-rior cruciate ligament reconstruction using the contralateral bone-patellar tendon-bone graft. Instr Course Lect. 2002; 51:343-346.

58. Franceschi F, Papalia R, Del Buono A, et al. Two-stage procedure in anterior cruciate ligament revision surgery: a five-year fol-low-up prospective study. Int Orthop. 2013; 37(7):1369-1374.

59. Erickson BJ, Harris JD, Heninger JR, et al. Performance and return-to-sport after ACL reconstruction in NFL quarterbacks. Ortho-pedics. 2014; 37(8):e728-e734.

60. Erickson BJ, Harris JD, Cvetanovich GL, et al. Performance and return-to-sport after anterior cruciate ligament reconstruction in male Major League Soccer players. Orthop J Sports Med. 2013; 1(2):2325967113497189.

61. Erickson BJ, Harris JD, Fillingham YA, et al. Performance and return to sport after anterior cruciate ligament reconstruction in X-Games skiers and snowboarders. Orthop J Sports Med. 2013; 1(6):2325967113511196.

62. Harris JD, Erickson BJ, Bach BR Jr, et al. Return-to-sport and performance after ante-rior cruciate ligament reconstruction in Na-tional Basketball Association players. Sports Health. 2013; 5(6):562-568.

63. Namdari S, Scott K, Milby A, Baldwin K, Lee GC. Athletic performance after ACL reconstruction in the Women’s National Bas-ketball Association. Phys Sportsmed. 2011; 39(1):36-41.

64. Shelbourne KD, Benner RW, Gray T. Return to sports and subsequent injury rates after revision anterior cruciate ligament recon-struction with patellar tendon autograft. Am J Sports Med. 2014; 42(6):1395-1400.

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