title: Influence of graft source and configuration on revision rate and patient-reported outcomes after MPFL reconstruction: a systematic review and meta-analysis.
abstract: OBJECTIVE
  The purpose of this systematic review and meta-analysis was to determine the influence of graft source (allograft vs. autograft) and configuration (single-limbed vs. double-limbed) on failure rate and disease-specific patient-reported outcome (Kujala score) after medial patellofemoral ligament (MPFL) reconstruction for patellar instability.
  
  
  METHODS
  A systematic review of PubMed, Scopus, and the Cochrane Library was performed. A total of 31 studies met inclusion/exclusion criteria and were used to extract cohorts of patients who underwent ligament reconstruction with various allograft, autograft, single-limbed, and double-limbed constructs. Failure rates and postoperative improvements in Kujala scores were compared between cohorts using inverse-variance weighting in a random-effects analysis model and appropriate comparative statistical analyses (Chi-squared and independent samples t tests).
  
  
  RESULTS
  A total of 1065 MPFL reconstructions were identified in 31 studies. Autograft reconstructions were associated with greater postoperative improvements in Kujala scores when compared to allograft (32.2 vs. 22.5, p < 0.001), but there was no difference in recurrent instability (5.7 vs. 6.7 %, p = 0.74). Double-limbed reconstructions were associated with both improved postoperative Kujala scores (37.8 vs. 31.6, p < 0.001) and lower failure rate (10.6 vs. 5.5 %, p = 0.030).
  
  
  CONCLUSIONS
  MPFL reconstructions should be performed using double-limbed graft configurations. While autograft tendon may be associated with higher patient-reported outcomes in the absence of associated connective tissue disorders or ligamentous laxity, patient factors and allograft processing techniques should be carefully considered when selecting an MPFL graft source, as revision rates were no different between graft sources.
  
  
  METHODS
  IV.
authors: David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
authors: James M
authors: JM
authors: Weinberger
authors: Hospital for Special Surgery, New York, NY, USA.
authors: Peter D
authors: PD
authors: Fabricant
authors: Hospital for Special Surgery, New York, NY, USA.
authors: Samuel A
authors: SA
authors: Taylor
authors: David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
authors: Jenny Y
authors: JY
authors: Mei
authors: David Geffen School of Medicine at UCLA, Los Angeles, CA, USA. kjjonesmd@gmail.com.
authors: Kristofer J
authors: KJ
authors: Jones
mesh_terms: D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D007719:Knee Joint / Q000601:surgery; D008023:Ligaments, Articular / Q000601:surgery; D031222:Patellar Dislocation / Q000601:surgery*; D017847:Patellar Ligament / Q000601:surgery*; D057071:Patellofemoral Joint / Q000601:surgery*; D000071066:Patient Reported Outcome Measures; D019651:Plastic Surgery Procedures / Q000379:methods*; D013710:Tendons / Q000637:transplantation*; D014182:Transplantation, Autologous; D014184:Transplantation, Homologous; D019737:Transplants
keywords: Allograft; Autograft; Knee; Patellar dislocation; Patellar instability; Patellofemoral