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Outcomes of an Anatomic Posterolateral Knee Reconstruction
Robert F. LaPrade, MD, PhD1; Steinar Johansen, MD2; Julie Agel, MA1; May Arna Risberg, PT, PhD2; Havard Moksnes, PT2; Lars Engebretsen, MD, PhD2
1 Department of Orthopaedic Surgery, University of Minnesota, 2450 Riverside Avenue, R200, Minneapolis, MN 55454. E-mail address for R.F LaPrade: lapra001@umn.edu
2 Department of Orthopaedic Surgery, Ullevaal University Hospital, University of Oslo, N-0407 Oslo, Norway
View Disclosures and Other Information
Disclosure: In support of their research for or preparation of this work, one or more of the authors received, in any one year, outside funding or grants of less than $10,000 from the University of Oslo School of Medicine Orthopaedic Center. Neither they nor a member of their immediate families received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity.

Investigation performed at the Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, Minnesota, and the Department of Orthopaedic Surgery, Ullevaal University Hospital, University of Oslo, Oslo, Norway
A commentary by James P. Stannard, MD, is available at www.jbjs.org/commentary and as supplemental material to the online version of this article.
A video supplement to this article will be available from the Video Journal of Orthopaedics. A video clip will be available at the JBJS web site, www.jbjs.org. The Video Journal of Orthopaedics can be contacted at (805) 962-3410, web site: www.vjortho.com.

Copyright ©2010 American Society for Journal of Bone and Joint Surgery, Inc.
J Bone Joint Surg Am, 2010 Jan 01;92(1):16-22. doi: 10.2106/JBJS.I.00474
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Abstract

Background: 

Chronic posterolateral knee injuries often result in substantial patient morbidity and functional instability. The clinical stability and functional outcomes following anatomic reconstructions in patients with a chronic posterolateral knee injury have not been determined, to our knowledge.

Methods: 

A two-center outcomes study of sixty-four patients with grade-3 chronic posterolateral instability was performed. The patients were evaluated subjectively with the modified Cincinnati and International Knee Documentation Committee (IKDC) subjective scores and objectively with the IKDC objective score.

Results: 

Eighteen patients had an isolated posterolateral knee reconstruction, and forty-six patients underwent a single-stage multiple-ligament reconstruction that included reconstruction of one or both cruciate ligaments along with the posterolateral knee reconstruction. The average duration of follow-up was 4.3 years. The fifty-four patients who were available for follow-up had an average total Cincinnati score of 65.7 points. A significant improvement was found between the preoperative and postoperative IKDC objective scores for varus opening at 20°, external rotation at 30°, reverse pivot shift, and single-leg hop.

Conclusions: 

An anatomic posterolateral reconstruction resulted in improved clinical outcomes and objective stability for patients with a grade-3 posterolateral knee injury.

Level of Evidence: 

Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

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    References

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    Robert F. LaPrade, MD, PhD
    Posted on August 16, 2010
    Dr. LaPrade and colleagues respond to Drs. Apsingi and Eachampati
    Steadman Philippon Research Institute, Vail, Colorado

    We are writing back in regards to a letter from Dr. Sunil Apsingi from India on July 22, 2010 in regards to our anatomic posterolateral knee reconstruction outcomes study (1). Our current response is basically the same as our response to Dr. Frank Noyes on April 27, 2010.

    As per our response to Dr. Noyes, our response to Dr. Apsingi is that we have been questioned several times over the past decade about the necessity of reconstructing the popliteofibular ligament (PFL) through a tibial tunnel in our anatomic reconstruction. As we reported in this study (1) and in our 2004 biomechanical study (2) which validated this reconstruction technique, it is important to recognize that the PFL forms a 38° proximomedial angle as it courses off the fibula (3) to its attachment at the popliteus musculotendinous junction and this is the angle our PFL reconstruction graft makes when it enters the tibia (1-2).

    It is very timely that Dr. Apsingi questions us about this portion of our reconstruction because a recent AJSM article from our lab answered this question (4). In this study, we found that a PFL reconstruction through a tibial tunnel restores knee motion back to normal, without overconstraint of the knee, while a reconstruction which does not have this portion of the posterolateral corner reconstruction has small but significant increases in residual knee laxity (4). Thus, we have validated that this part of the reconstruction is a necessary part of our reconstruction technique (1-2).

    Therefore, we still affirm that in order to restore knee kinematics to the normal state, a reconstruction including the fibular collateral ligament (FCL), popliteus tendon, and PFL are necessary and should be performed according to our described technique (1-2).

    We theorized that the reason this is necessary is that the PFL portion of our reconstruction technique must provide increased stability to varus for the FCL portion of our reconstruction. It is very clear to us from our anatomic FCL reconstruction (5) and our anatomic posterolateral reconstruction technique (1,2) that the FCL graft greatly restores the overall varus stability of the knee which we believe is the key portion of our anatomic reconstruction. Thus, using the PFL part of the reconstruction is an essential part of our anatomic reconstruction to restore stability to the normal state.

    We wish to thank Dr. Apsingi for allowing us to further expand on our anatomical posterolateral corner reconstruction technique.

    References

    1. LaPrade RF, Johansen S, Agel J, Risberg MA, Moksnes H, Engebretsen L. Outcomes of an anatomic posterolateral knee reconstruction. J Bone Joint Surg Am. 2010;92:16-22.

    2. LaPrade RF, Johansen S, Wentorf FA, Engebretsen L, Esterberg JL, Tso A. An analysis of an anatomical posterolateral knee reconstruction: an in vitro biomechanical study and development of a surgical technique. Am J Sports Med. 2004;32:1405-14.

    3. LaPrade RF, Ly TV, Wentorf FA, Engebretsen L. The posterolateral attachments of the knee: a qualitative and quantitative morphologic analysis of the fibular collateral ligament, popliteus tendon, popliteofibular ligament, and lateral gastrocnemius tendon. Am J Sports Med. 2003;31:854-60.

    4. McCarthy M, Camarda L, Wijdicks CA, Johansen S, Engebretsen L, LaPrade RF. Anatomic posterolateral knee reconstructions require a popliteofibular ligament reconstruction through a tibial tunnel. Am J Sports Med. 2010;38:1674-81.

    5. LaPrade RF, Spirindonov SI, Coobs BR, Ruckert PR, Griffith CJ. Fibular collateral ligament anatomical reconstructions: a prospective outcomes study. Am J Sports Med. 2010 Jul 1 [Epub ahead of print].

    Sunil Apsingi
    Posted on July 20, 2010
    Is the Reconstruction Really Anatomical?
    Krishna Institute of Medical Sciences, Secunderabad, India.

    To the Editor:

    We read the article, "Outcomes of an anatomic posterolateral knee reconstruction", by LaPrade et al. with great interest (2010;92:16-22). The reconstruction performed by them does not reconstruct the popliteofibular ligament. They have reconstructed a tibiofibular ligament which has no role in controlling the external rotation. An anatomical study of the posterolateral corner of the knee published by LaPrade et al. (1) clearly demonstrates that the popliteofibular ligament arises from the tendon of the popliteus and insets on to the fibula (Figure 7D in reference 1). Hence the authors are contradicting their anatomical findings and have misleadingly named their reconstruction as anatomical.

    The authors did not receive any outside funding or grants in support of their research for or preparation of this work. Neither they nor a member of their immediate families received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity.

    References

    1. Terry GC, LaPrade RF. The posterolateral aspect of the knee. Anatomy and surgical approach. Am J Sports Med. 1996;24:732-9.

    Robert F. LaPrade, MD, PhD
    Posted on April 30, 2010
    Dr. LaPrade and colleagues respond to Dr. Noyes
    The Steadman Clinic, Vail, Colorado

    We wish to thank Dr. Noyes for his kind letter about our anatomic posterolateral knee reconstruction outcomes study. Dr. Noyes obviously has a great deal of experience in this area and we respect his comments and his work. However, we do disagree with some of his statements based upon our own anatomic and biomechanical studies.

    We do concur with Dr. Noyes that we have been questioned several times from the podium over the past decade about the necessity of reconstructing the popliteofibular ligament through a tibial tunnel in our anatomic reconstruction. As we reported in this study (1) and in our 2004 biomechanics study (2) which validated this reconstruction technique, we also agree with Dr. Noyes that the popliteofibular ligament (PFL) graft should not be horizontal and we have reported that it forms a 37° proximomedial angle as it courses off the fibula (3) to its attachment at the popliteus musculotendinous junction and this is the angle our PFL reconstruction graft makes when it enters the tibia (1,2). It is very timely that he asks about this portion of our reconstruction because a recent biomechanical study from our lab answers this question. In this study, we found that a PFL reconstruction through a tibial tunnel restores knee motion back to normal, without overconstraint of the knee, while a reconstruction which does not have this part of the reconstruction has significant increases in residual knee laxity (4). Thus, we have validated that this is a necessary part of our reconstruction technique (1,2).

    Therefore, we do believe that in order to restore knee kinematics to the normal state, a reconstruction including the fibular collateral ligament, the popliteus tendon, and the PFL are necessary and should be performed according to our described technique (1,2).

    We were also well aware of Dr. Noyes’ fibular collateral ligament reconstruction technique using a patellar tendon graft to treat posterolateral instability which he referred to in his letter (5). However, we are sure that Dr. Noyes will agree that this technique does not address a grade III posterolateral knee injury with a concurrent popliteus complex injury, which was the topic of our article. In addition, we also wish to kindly point out that because the average length of the fibular collateral ligament has been reported to be 71 mm (6), and that the average length of the patellar tendon is 48 mm (7), that in fact a semitendinosus autograft to reconstruct the fibular collateral ligament (8,9) is a better option to more anatomically reproduce the anatomic length of this ligament for the majority of patients.

    Once again, we wish to thank Dr. Noyes for his comments and agree that further research is necessary to treat this complex problem.

    References

    1. LaPrade RF, Johansen S, Agel J, Risberg MA, Moksnes H, Engebretsen L. Outcomes of an anatomic posterolateral knee reconstruction. J Bone Joint Surg Am. 2010;92:16-22.

    2. LaPrade RF, Johansen S, Wentorf FA, Engebretsen L, Esterberg JL, Tso A. An analysis of an anatomical posterolateral knee reconstruction: an in vitro biomechanical study and development of a surgical technique. Am J Sports Med. 2004;32:1405-14.

    3. LaPrade RF, Ly TV, Wentorf FA, Engebretsen L. The posterolateral attachments of the knee: a qualitative and quantitative morphologic analysis of the fibular collateral ligament, popliteus tendon, popliteofibular ligament, and lateral gastrocnemius tendon. Am J Sports Med. 2003;31:854-60.

    4. McCarthy M, Camarda L, Wijdicks CA, Johansen S, Engebretsen L, LaPrade RF. Anatomic posterolateral knee reconstructions require a popliteofibular ligament reconstruction though a tibial tunnel. Am J Sports Med. In press.

    5. Noyes FR, Barber-Westin SD. Posterolateral knee reconstruction with an anatomical bone-patellar tendon-bone reconstruction of the fibular collateral ligament. Am J Sports Med. 2007;35:259-73.

    6. LaPrade RF, Hamilton CD. The fibular collateral ligament-biceps femoris bursa. An anatomic study. Am J Sports Med. 1997;25:439-43.

    7. LaPrade RF. The anatomy of the deep infrapatellar bursa of the knee. Am J Sports Med. 1998;26:129-32.

    8. Coobs BR, LaPrade RF, Griffith CJ, Nelson BJ. Biomechanical analysis of an isolated fibular (lateral) collateral ligament reconstruction using an autogenous semitendinosus graft. Am J Sports Med. 2007;35:1521-7.

    9. LaPrade RF, Spiridonov SI, Coobs BR, Ruckert PR, Griffith CJ. Fibular collateral ligament anatomic reconstructions: A prospective outcomes study. Am J Sports Med. In press.

    Frank R. Noyes, MD
    Posted on March 22, 2010
    Regarding LaPrade et al., “Outcomes of an Anatomic Posterolateral Knee Reconstruction”
    Cincinnati Sportsmedicine Research and Orthopaedic Center, Cincinnati, Ohio

    To the Editor:

    I would like to comment on the recently published article of LaPrade et al., “Outcomes of an Anatomic Posterolateral Knee Reconstruction” (1). I congratulate the authors on their continued work on posterolateral knee injuries and the positive clinical outcomes of their operative procedure designed to restore insufficient posterolateral knee ligament structures. I would like to offer a few points and recommendation on the use of the term “anatomic reconstruction” for posterolateral knee instability.

    The first point relates to the authors’ statement of the lack of prior publications on the clinical outcomes of anatomic posterolateral knee reconstructions. The commentary by James P. Stannard provided references of his work (2,3) and that of Schechinger et al. (4) who he believed had published clinical outcomes on so-called “anatomic reconstructions”. However, the Stannard procedure (2) involved a fibular collateral ligament graft and a popliteus tendon graft which were attached together by a screw-washer fixation device at one site on the femur in a non-anatomic configuration instead of replicating the normal anatomic separation between these two structures. Schechinger et al.(4) described a posterolateral reconstruction in which there were separate anatomic attachments of the popliteus tendon and fibular collateral ligament at the anatomic femoral sites. However, the grafts attached entirely to the fibula without reconstructing the popliteus tendon-tibia static arm.

    Accordingly, LaPrade et al. appear justified in stating that these operative procedures would probably not represent true “anatomic” reconstructions. However, in 2007, we published what I believe was the first description of the clinical outcomes of an anatomic posterolateral knee reconstruction (5) which was not referenced in LaPrade et al.’s publication.

    The second point relates to the term “anatomic” posterolateral knee reconstruction which involves restoring the attachment points and orientation of three structures, namely, the fibular collateral ligament, the popliteus tendon femoral-tibia static attachment, and the popliteofibular ligament (popliteus tendon to fibular attachment). As suggested by Stannard’s commentary, it would appear that confusion exists regarding what posterolateral reconstruction procedure is “more anatomic” than others, and I would add that the clinical relevance of this issue is still not defined by clinical outcome studies.

    For example, in the “anatomic reconstruction” described by LaPrade et al., the fibular collateral ligament and popliteus femoral-tibial static portion are replaced by grafts attached at native anatomic femoral and tibial insertion points. This is also true for the “anatomic” graft substitution procedure for these two structures that we previously described (5). However, in the LaPrade procedure, the popliteofibular ligament graft does not represent the native anatomic structure. Instead, the graft attachment is from the posterior proximal fibula to the posterior tibia tunnel. The popliteofibular ligament graft occupies a horizontal position which does not simulate the more vertical position of the popliteofibular ligament anatomic attachment to the proximal popliteus tendon, which is required to resist varus and external tibial rotation loading.

    In a study conducted at our center (5), the popliteofibular ligament was restored by suturing a portion of the popliteus tendon graft to the fibular collateral ligament fibular attachment. A separate popliteofibular ligament graft was purposely avoided to prevent the risk of weakening the proximal fibular attachment of the more important fibular collateral ligament graft. A prior biomechanical investigation from our center (6) showed that removal of the popliteofibular ligament produced no increases in external tibial rotation and lateral joint opening under loading conditions as long as the other posterolateral structures were intact. We concluded that the fibular collateral ligament and popliteus tendon femoral-tibial attachment were the two primary structures that required reconstruction to resist lateral joint opening under varus loads and increased external tibial rotation.

    It is also important, and not stressed by the authors, that operative procedures should involve restoring a functional posterolateral capsule which includes attachments of the oblique popliteal ligament, the fabellofibular ligament, and the proximal popliteus capsular expansion (7). These structures provide important resistance to abnormal knee hyperextension, along with the cruciate ligaments. In the operative procedure we described (5), we identified this as the fourth anatomic structure to restore and recommended plication or advancement procedures. In select knees, a graft reconstruction for these structures may be required if a severe varus recurvatum exists and the posterolateral capsular structures are entirely deficient (8).

    My recommendation is that a so-called “anatomic” posterolateral knee ligament reconstruction should at the minimum restore three primary structures: the fibular collateral ligament, the popliteus tendon femoral- tibial portion, and the posterolateral capsule. The addition of the popliteofibular ligament as a separate structure may be argued as a fourth structure; however, this is open for debate. Accordingly, it is ideal for publications to precisely describe the operative details of what structures were restored or reconstructed. The term “anatomic” as currently applied by authors appears to be ambiguous for reasons discussed above. I believe in the future there will be a number of different operations claiming to be “anatomic posterolateral knee reconstructions” when in fact there are major differences in graft attachments and operative procedures.

    Our study used stress radiography to obtain an objective measurement of lateral joint opening before and after surgery and this would have provided objective data as an added benefit in interpreting the results of LaPrade et al. In addition, LaPrade et al. stated they did not collect preoperative functional data because there were no validated knee outcome instruments at that time period (2000) when in fact there were such rating systems available (9,10). The authors did not provide an analysis of the difference in knee function before surgery and at the latest follow-up examination. The reporting of only averages and ranges for these scores does not indicate the percentage of patients who were asymptomatic or symptomatic at follow-up or what types of activities they had returned to (daily activities or sports). It is not my intention for these comments to detract from the authors’ study, as it represents a significant work that is important for surgeons to study for treating posterolateral knee ligament injuries.

    It remains my observation that the most frequent operation still used for posterolateral knee reconstruction is a femoral-fibular graft reconstruction. To date, there have been ten published clinical outcome studies(2,4,11-18) on femoral-fibular reconstructions; however, only two (12,18) used stress radiographs to provide an objective measurement of lateral joint opening. Thus, a clinical comparison of the results of “anatomic” to “femoral-fibular “reconstructions is not possible and requires additional clinical studies. The concern is that a femoral-fibular procedure without the popliteus-tibia static arm may provide an unacceptable high failure rate for severe Grade 3 posterolateral instabilities.

    As a final point, there is a contrasting point of view that posterolateral ligament reconstructions should be based on grafts attached at isometric graft locations determined at surgery instead of native anatomic insertions. These isometric points are in fact markedly different than native anatomic attachment sites (19). Although not ascribing to this viewpoint, the issue speaks again to the necessity for the surgeon to precisely describe the attachment locations for the grafts selected in posterolateral knee reconstructions.

    The author did not receive any outside funding or grants in support of his research for or preparation of this work. Neither he nor a member of his immediate family received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity.

    References

    1. LaPrade RF, Johansen S, Agel J, Risberg MA, Moksnes H, Engebretsen L. Outcomes of an anatomic posterolateral knee reconstruction. J Bone Joint Surg Am. 2010;92:16-22.

    2. Stannard JP, Brown SL, Farris RC, McGwin G Jr, Volgas DA. The posterolateral corner of the knee: repair versus reconstruction. Am J Sports Med. 2005;33:881-8.

    3. Stannard JP, Brown SL, Robinson JT, McGwin G Jr, Volgas DA. Reconstruction of the posterolateral corner of the knee. Arthroscopy. 2005;21:1051-9.

    4. Schechinger SJ, Levy BA, Dajani KA, Shah JP, Herrera DA, Marx RG. Achilles tendon allograft reconstruction of the fibular collateral ligament and posterolateral corner. Arthroscopy. 2009;25:232-42.

    5. Noyes FR, Barber-Westin SD. Posterolateral knee reconstruction with an anatomical bone-patellar tendon-bone reconstruction of the fibular collateral ligament. Am J Sports Med. 2007;35:259-73.

    6. Pasque C, Noyes FR, Gibbons M, Levy M, Grood E. The role of the popliteofibular ligament and the tendon of popliteus in providing stability in the human knee. J Bone Joint Surg Br. 2003;85:292-8.

    7. Strickland JP, Fester EW, Noyes FR. Lateral, posterior, and cruciate knee anatomy. In: Noyes FR, editor. Knee disorders: surgery, rehabilitation, clinical outcomes. Philadelphia: Saunders/Elsevier; 2009. p 20-43.

    8. Noyes FR, Barber-Westin SD. Posterolateral ligament injuries: diagnosis, operative techniques, and clinical outcomes. In: Noyes FR, editor. Knee disorders: surgery, rehabilitation, clinical outcomes. Philadelphia: Saunders/Elsevier; 2009. p 577-630.

    9. Barber-Westin SD, Noyes FR, McCloskey JW. Rigorous statistical reliability, validity, and responsiveness testing of the Cincinnati knee rating system in 350 subjects with uninjured, injured, or anterior cruciate ligament-reconstructed knees. Am J Sports Med. 1999;27:402-16.

    10. Roos EM, Roos HP, Lohmander LS, Ekdahl C, Beynnon BD. Knee Injury and Osteoarthritis Outcome Score (KOOS)—development of a self-administered outcome measure. J Orthop Sports Phys Ther. 1998;28:88-96.

    11. Zhao J, He Y, Wang J. Anatomical reconstruction of knee posterolateral complex with the tendon of the long head of biceps femoris. Am J Sports Med. 2006;34:1615-22.

    12. Buzzi R, Aglietti P, Vena LM, Giron F. Lateral collateral ligament reconstruction using a semitendinosus graft. Knee Surg Sports Traumatol Arthrosc. 2004;12:36-42.

    13. Strobel MJ, Schulz MS, Petersen WJ, Eichhorn HJ. Combined anterior cruciate ligament, posterior cruciate ligament, and posterolateral corner reconstruction with autogenous hamstring grafts in chronic instabilities. Arthroscopy. 2006;22:182-92.

    14. Harner CD, Waltrip RL, Bennett CH, Francis KA, Cole B, Irrgang JJ. Surgical management of knee dislocations. J Bone Joint Surg Am. 2004;86:262-73.

    15. Fanelli GC, Edson CJ. Combined posterior cruciate ligament-posterolateral reconstructions with Achilles tendon allograft and biceps femoris tendon tenodesis: 2- to 10-year follow-up. Arthroscopy. 2004;20:339-45.

    16. Cooper DE, Stewart D. Posterior cruciate ligament reconstruction using single-bundle patella tendon graft with tibial inlay fixation: 2- to 10-year follow-up. Am J Sports Med. 2004;32:346-60.

    17. Latimer HA, Tibone JE, ElAttrache NS, McMahon PJ. Reconstruction of the lateral collateral ligament of the knee with patellar tendon allograft. Report of a new technique in combined ligament injuries. Am J Sports Med. 1998;26:656-62.

    18. Noyes FR, Barber-Westin SD. Surgical reconstruction of severe chronic posterolateral complex injuries of the knee using allograft tissues. Am J Sports Med. 1995;23:2-12.

    19. Sigward SM, Markolf KL, Graves BR, Chacko JM, Jackson SR, McAllister DR. Femoral fixation sites for optimum isometry of posterolateral reconstruction. J Bone Joint Surg Am. 2007;89:2359-68.

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