title: Clinical outcomes of medial patellofemoral ligament reconstruction in patients with an increased tibial tuberosity-trochlear groove distance.
abstract: OBJECTIVE
  Medial patellofemoral ligament (MPFL) reconstruction is performed to treat recurrent patellar dislocation (RPD). However, the effectiveness of MPFL reconstruction in patients with a severely lateralised tibial tuberosity remains unknown. In this study, the clinical outcomes of MPFL reconstruction in patients with an increased tibial tuberosity-trochlear groove (TT-TG) distance were examined.
  
  
  METHODS
  A total of thirty-four patients who underwent MPFL reconstruction for RPD were retrospectively examined. Nineteen patients with a TT-TG distance of >20 mm (increased TT-TG distance group) were compared with 15 patients with a TT-TG distance of <20 mm (control group). Clinical outcomes of MPFL reconstruction were evaluated by occurrence of re-dislocation, Crosby and Insall grading system, apprehension sign, and Kujala and Lysholm scores.
  
  
  RESULTS
  None of the patients reported re-dislocation. Apprehension sign remained in three patients in the increased TT-TG distance group and in one patient in the control group. According to the Crosby and Insall grading system, 9 patients (47%) were excellent, 9 (47%) were good, and 1 (5%) was fair to poor in the increased TT-TG distance group, while 6 (40%) were excellent and 9 (60%) were good in the control group. Kujala and Lysholm scores were significantly improved post-operatively in both groups. No significant correlations were observed between TT-TG distance and post-operative Kujala or Lysholm score.
  
  
  CONCLUSIONS
  Overall clinical outcomes of MPFL reconstruction were favourable even in patients with an increased TT-TG distance. TT-TG distance of >20 mm may not be an absolute indication for medialisation of the tibial tuberosity when performing MPFL reconstruction.
  
  
  METHODS
  Case-control study, Level III.
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-Cho, Chuo-Ku, Kobe, Hyogo, 650-0017, Japan.
authors.forename: Takehiko
authors.initials: T
authors.lastname: Matsushita
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kuroda
authors.forename: Shinya
authors.initials: S
authors.lastname: Oka
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Koji
authors.initials: K
authors.lastname: Takayama
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kurosaka
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D031222:Patellar Dislocation / Q000601:surgery*; D011859:Radiography; D012189:Retrospective Studies; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery*; D055815:Young Adult