title: Clinical outcome after reconstruction of the medial patellofemoral ligament in patients with recurrent patella instability.
abstract: OBJECTIVE
  We present the clinical results of a large consecutive, prospective, single-clinic series of patients treated with medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar instability.
  
  
  METHODS
  The study included 224 patients undergoing MPFL reconstruction in a total of 240 knees between 2008 and 2011. Indication for surgery was two or more patellar dislocations and ADL limitations due to patella instability.
  
  
  METHODS
  A gracilis tendon autograft was fixed in drill holes in the medial edge of the patella and with screws at the femoral MPFL insertion point. Outcomes were evaluated with the Kujala Anterior Knee Pain Score and pain scores preoperatively and at follow-up (12-60 months). Furthermore, incidences of re-dislocations, subluxations and revision surgery were evaluated.
  
  
  RESULTS
  The Kujala score improved from 62.5 (17) to 80.4 (18) (p<0.001) at the 1-year follow-up. Pain during activity improved from 3.2 (2.6) to 1.3 (2.7) at 1 year (p<0.001). The revision rate was 2.8%. Some degree of pain at the medial femoral condyle was seen in 30% of the patients. The reconstruction was supplemented with a tibial tuberosity osteotomy in 23% of cases. The outcome for these patients did not differ from that of patients with isolated MPFL reconstruction. Female gender BMI>30, age>30 years and grade 3-4 cartilage injury predisposed a poor subjective outcome.
  
  
  CONCLUSIONS
  The present study is the largest MPFL reconstruction patient material reported to date. MPFL reconstruction with a gracilis tendon autograft consistently normalised the patella stability and improved knee function. Moderate medial pain was seen. Age above 30, obesity, cartilage injury and female gender are predictors of a poor subjective outcome.
  
  
  METHODS
  Level IV.
authors.affiliation: Division of Sports Trauma, Orthopaedic Department, Aarhus University Hospital, Tage Hansens Gade 2, 8000, Aarhus C, Denmark.
authors.forename: Ditte
authors.initials: D
authors.lastname: Enderlein
authors.forename: Torsten
authors.initials: T
authors.lastname: Nielsen
authors.forename: Svend Erik
authors.initials: SE
authors.lastname: Christiansen
authors.forename: Peter
authors.initials: P
authors.lastname: Faunø
authors.forename: Martin
authors.initials: M
authors.lastname: Lind
mesh_terms: D000293:Adolescent; D000328:Adult; D001178:Arthroplasty / Q000706:statistics & numerical data*; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010027:Osteotomy; D010329:Patella / Q000601:surgery; D031222:Patellar Dislocation / Q000601:surgery*; D057071:Patellofemoral Joint / Q000601:surgery*; D011446:Prospective Studies; D019651:Plastic Surgery Procedures / Q000379:methods; D013710:Tendons / Q000637:transplantation; D013977:Tibia / Q000601:surgery; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D055815:Young Adult