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Editorial Commentary: Autograft Beats Allograft for Most Knee Ligament Surgery

      Abstract

      Knee ligament reconstruction can be performed with autograft or allograft. The use of an autograft has been shown to improve outcomes in primary anterior cruciate ligament reconstruction for young, active patients, and also in revision anterior cruciate ligament reconstruction surgery. A systematic review of posterior cruciate ligament reconstruction showed no difference in outcomes between autograft and allograft tissue. There is a paucity of data comparing autograft versus allograft for fibular collateral ligament and posterolateral corner reconstructions, alone or combined with other ligament surgery. Allograft advantages include no donor site morbidity and reduced operative time. Disadvantages include increased cost and higher failure rates in younger patients. Autograft tissue should be considered in younger, active patients whenever possible.
      The use of an autograft has been shown to improve outcomes in primary anterior cruciate ligament (ACL) reconstruction for young, active patients
      • Kaeding C.C.
      • Aros B.
      • Pedroza A.
      • et al.
      Allograft versus autograft anterior cruciate ligament reconstruction: Predictors of failure from a MOON prospective longitudinal cohort.
      and also in revision ACL reconstruction surgery.
      MARS Group
      Effect of graft choice on the outcome of revision anterior cruciate ligament reconstruction in the Multicenter ACL Revision Study (MARS) Cohort.
      A systematic review of posterior cruciate ligament (PCL) reconstruction showed no difference in outcomes between autograft and allograft tissue.
      • Hudgens J.L.
      • Gillette B.P.
      • Krych A.J.
      • Stuart M.J.
      • May J.H.
      • Levy B.A.
      Allograft versus autograft in posterior cruciate ligament reconstruction: An evidence-based systematic review.
      There is a paucity of data comparing autograft versus allograft for fibular collateral (FCL) and posterolateral (PLC) reconstructions.
      The retrospective cohort study titled “Isolated Fibular Collateral Ligament Reconstruction Graft Options in the Setting of Anterior Cruciate Ligament Reconstruction: Clinical and Radiographic Outcomes of Autograft Versus Allograft,”
      • Dekker T.J.
      • Schairer W.
      • Grantham W.J.
      • DePhillipo N.N.
      • Aman Z.S.
      • LaPrade R.F.
      Isolated fibular collateral ligament reconstruction graft options in the setting of anterior cruciate ligament reconstruction: Clinical and radiographic outcomes of autograft versus allograft.
      by Dekker, Schairer, Grantham, DePhillipo, Aman, and LaPrade, compared outcomes of FCL reconstruction using autograft versus allograft in the setting of combined ACL/isolated FCL reconstructions. PLC reconstructions were not included. The indication for isolated FCL reconstruction at the time of ACL reconstruction was a side-to-side difference of ≥2 mm on bilateral varus stress radiographs. Postoperative assessment using varus stress views was performed at a minimum of 6 months after surgery, and all patients had 2-year minimum clinical follow-up. The authors excluded children and patients older than 55 years, as well as revision and multiple ligament reconstruction cases.
      Patellar tendon autograft or allograft was used for all ACL reconstructions. FCL reconstruction using semitendinosus autograft (50 patients) was compared with semitendinosus or tibialis anterior allograft (19 patients). The authors found no difference in any of the parameters tested and reported no complications or graft failures.
      The authors recognized several important study limitations, and their results should be interpreted with caution. Meniscus or cartilage status was not reported, and the groups were not matched for age, activity level, body mass index, sex, sport, time to surgery, ACL or FCL graft type. The lack of matching and ACL graft control makes it difficult to know whether the results were secondary to the type of FCL and ACL reconstruction graft or from the multiple confounding variables above. An a priori power analysis was performed, but there were more than twice as many autografts than allografts.
      Selection bias resulted from the surgeon choosing both the ACL and FCL grafts. Older patients received allografts, and younger patients received autografts, producing a statistically significant age difference. Numerous studies have shown that older patients have lower functional levels which may translate to better patient-reported outcomes and minimize differences between the groups.
      • Grindem H.
      • Engebretsen L.
      • Axe M.
      • Snyder-Mackler L.
      • Risberg M.A.
      Activity and functional readiness, not age, are the critical factors for second anterior cruciate ligament injury—The Delaware-Oslo ACL cohort study.
      • Webster K.E.
      • Feller J.A.
      Return to level I sports after anterior cruciate ligament reconstruction: Evaluation of age, sex, and readiness to return criteria.
      • Webster K.E.
      • Feller J.A.
      Younger patients and men achieve higher outcome scores than older patients and women after anterior cruciate ligament reconstruction.
      The varus stress radiographs performed at 6 months after surgery did not test grafts that were subjected to repetitive stress over time. LaPrade et al.
      • LaPrade R.F.
      • Spiridonov S.I.
      • Coobs B.R.
      • Ruckert P.R.
      • Griffith C.J.
      Fibular collateral ligament anatomical reconstructions: A prospective outcomes study.
      demonstrated that varus stress test stability was maintained at 2-year follow-up after autograft FCL reconstruction. These results have not yet been replicated for allograft FCL reconstruction, so long-term, objective assessment is required. It is also important to recognize that the soft tissue integration of allografts is slower than that of autograft tissue. Basic science and magnetic resonance imaging (MRI) studies have shown that bone integration is incomplete at 6 months after allograft ligament reconstruction.
      • Gulotta L.V.
      • Rodeo S.A.
      Biology of autograft and allograft healing in anterior cruciate ligament reconstruction.
      • Muller B.
      • Bowman Jr., K.F.
      • Bedi A.
      ACL graft healing and biologics.
      • Ge Y.
      • Li H.
      • Tao H.
      • Hua Y.
      • Chen J.
      • Chen S.
      Comparison of tendon-bone healing between autografts and allografts after anterior cruciate ligament reconstruction using magnetic resonance imaging.
      In addition, higher failure rates are associated with the use of allograft for ligament reconstruction in younger populations.
      • Kaeding C.C.
      • Aros B.
      • Pedroza A.
      • et al.
      Allograft versus autograft anterior cruciate ligament reconstruction: Predictors of failure from a MOON prospective longitudinal cohort.
      ,
      MARS Group
      Effect of graft choice on the outcome of revision anterior cruciate ligament reconstruction in the Multicenter ACL Revision Study (MARS) Cohort.
      ,
      • Hulet C.
      • Sonnery-Cottet B.
      • Stevenson C.
      • et al.
      The use of allograft tendons in primary ACL reconstruction.
      The ACL is recognized as a secondary stabilizer to varus laxity. In cadaver studies, lateral joint space widening increased with complete FCL/ACL tears compared with isolated FCL injuries.
      • LaPrade R.F.
      • Spiridonov S.I.
      • Coobs B.R.
      • Ruckert P.R.
      • Griffith C.J.
      Fibular collateral ligament anatomical reconstructions: A prospective outcomes study.
      ,
      • Ramos L.A.
      • Zogbi T.
      • de Andrade E.F.
      • et al.
      Treatment and outcomes of lateral collateral ligament injury associated with anterior and posterior cruciate ligament injury at 2-year follow-up.
      ,
      • McDonald L.S.
      • Waltz R.A.
      • Carney J.R.
      • et al.
      Validation of varus stress radiographs for anterior cruciate ligament and posterolateral corner knee injuries: A biomechanical study.
      McDonald et al.
      • McDonald L.S.
      • Waltz R.A.
      • Carney J.R.
      • et al.
      Validation of varus stress radiographs for anterior cruciate ligament and posterolateral corner knee injuries: A biomechanical study.
      documented increased lateral laxity of ≤1.1 mm in isolated ACL sectioning and ≤2 mm after sectioning both the ACL and FCL. This supports the authors’ 2-mm cutoff for combined ACL/FCL reconstruction. However, LaPrade et al.
      • LaPrade R.F.
      • Heikes C.
      • Bakker A.J.
      • Jakobsen R.B.
      The reproducibility and repeatability of varus stress radiographs in the assessment of isolated fibular collateral ligament and grade-III posterolateral knee injuries. An in vitro biomechanical study.
      showed a 2.7-mm increase in lateral side laxity with sectioning of the FCL alone; therefore, an injury to both the ACL and FCL is likely greater than the 2-mm difference used to determine surgical indications.

      Take-Home Points

      The authors should be commended for studying a unique, combined knee ligament injury pattern (ACL/isolated FCL) that lacks high-level research. The comparison of allograft to autograft for FCL reconstruction did not reach significance, but we still believe that autograft tissue should be considered in younger, active patients whenever possible. Future studies with a matched cohort analysis controlling for demographic data and meniscus and cartilage status, as well as ACL graft type, or a randomized controlled trial is required to provide definitive answers regarding the ideal graft type in combined ACL/isolated FCL reconstruction.

      Supplementary Data

      References

        • Kaeding C.C.
        • Aros B.
        • Pedroza A.
        • et al.
        Allograft versus autograft anterior cruciate ligament reconstruction: Predictors of failure from a MOON prospective longitudinal cohort.
        Sports Health. 2011; 3: 73-81
        • MARS Group
        Effect of graft choice on the outcome of revision anterior cruciate ligament reconstruction in the Multicenter ACL Revision Study (MARS) Cohort.
        Am J Sports Med. 2014; 42: 2301-2310
        • Hudgens J.L.
        • Gillette B.P.
        • Krych A.J.
        • Stuart M.J.
        • May J.H.
        • Levy B.A.
        Allograft versus autograft in posterior cruciate ligament reconstruction: An evidence-based systematic review.
        J Knee Surg. 2013; 26: 109-115
        • Dekker T.J.
        • Schairer W.
        • Grantham W.J.
        • DePhillipo N.N.
        • Aman Z.S.
        • LaPrade R.F.
        Isolated fibular collateral ligament reconstruction graft options in the setting of anterior cruciate ligament reconstruction: Clinical and radiographic outcomes of autograft versus allograft.
        Arthroscopy. 2021; 37: 944-950
        • Grindem H.
        • Engebretsen L.
        • Axe M.
        • Snyder-Mackler L.
        • Risberg M.A.
        Activity and functional readiness, not age, are the critical factors for second anterior cruciate ligament injury—The Delaware-Oslo ACL cohort study.
        Br J Sports Med. 2020; 54: 1099-1102
        • Webster K.E.
        • Feller J.A.
        Return to level I sports after anterior cruciate ligament reconstruction: Evaluation of age, sex, and readiness to return criteria.
        Orthop J Sports Med. 2018; 6 (2325967118788045)
        • Webster K.E.
        • Feller J.A.
        Younger patients and men achieve higher outcome scores than older patients and women after anterior cruciate ligament reconstruction.
        Clin Orthop Relat Res. 2017; 475: 2472-2480
        • LaPrade R.F.
        • Spiridonov S.I.
        • Coobs B.R.
        • Ruckert P.R.
        • Griffith C.J.
        Fibular collateral ligament anatomical reconstructions: A prospective outcomes study.
        Am J Sports Med. 2010; 38: 2005-2011
        • Gulotta L.V.
        • Rodeo S.A.
        Biology of autograft and allograft healing in anterior cruciate ligament reconstruction.
        Clin Sports Med. 2007; 26: 509-524
        • Muller B.
        • Bowman Jr., K.F.
        • Bedi A.
        ACL graft healing and biologics.
        Clin Sports Med. 2013; 32: 93-109
        • Ge Y.
        • Li H.
        • Tao H.
        • Hua Y.
        • Chen J.
        • Chen S.
        Comparison of tendon-bone healing between autografts and allografts after anterior cruciate ligament reconstruction using magnetic resonance imaging.
        Knee Surg Sports Traumatol Arthrosc. 2015; 23: 954-960
        • Hulet C.
        • Sonnery-Cottet B.
        • Stevenson C.
        • et al.
        The use of allograft tendons in primary ACL reconstruction.
        Knee Surg Sports Traumatol Arthrosc. 2019; 27: 1754-1770
        • Ramos L.A.
        • Zogbi T.
        • de Andrade E.F.
        • et al.
        Treatment and outcomes of lateral collateral ligament injury associated with anterior and posterior cruciate ligament injury at 2-year follow-up.
        J Orthop. 2019; 16: 489-492
        • McDonald L.S.
        • Waltz R.A.
        • Carney J.R.
        • et al.
        Validation of varus stress radiographs for anterior cruciate ligament and posterolateral corner knee injuries: A biomechanical study.
        Knee. 2016; 23: 1064-1068
        • LaPrade R.F.
        • Heikes C.
        • Bakker A.J.
        • Jakobsen R.B.
        The reproducibility and repeatability of varus stress radiographs in the assessment of isolated fibular collateral ligament and grade-III posterolateral knee injuries. An in vitro biomechanical study.
        J Bone Joint Surg Am. 2008; 90: 2069-2076