title: Fluoroscopic control allows for precise tunnel positioning in MPFL reconstruction.
abstract: OBJECTIVE
  In MPFL reconstruction, anatomical graft positioning is required to restore physiological joint biomechanics and patellofemoral stability. Considerable rates of non-anatomical femoral tunnel placement exist. The purpose of this study was to analyse whether intraoperative fluoroscopic control is applicable to reduce variability of femoral tunnel positioning.
  
  
  METHODS
  Femoral tunnel positions of 116 consecutive MPFL reconstructions applying intraoperative fluoroscopic images were analysed. Tunnel positions were determined by two independent observers according to Schöttle's radiographic measurement method. Mean positions, standard deviations and ranges were calculated to determine the variability of the tunnel positions. Interclass correlation coefficient (ICC) was calculated.
  
  
  RESULTS
  The mean anterior/posterior distances from the anatomical insertion of the MPFL to the centre of the femoral tunnel were 2.34 mm (range 0.0-5.9 mm) and 1.7 mm (range 0.1-7.3 mm, SD 1.3) for proximal/distal deviations; 95.7 % (111/116) of femoral tunnel positions were found to be within the anatomical insertion area defined by Schöttle. Interobserver tunnel position measurements were highly reliable (ICC: depth 0.979; height 0.979).
  
  
  CONCLUSIONS
  The study demonstrates that intraoperative fluoroscopic control is a feasible and effective method that enables to create reproducible and precise anatomical femoral tunnel positions in MPFL reconstruction. Accordingly, the routine use of intraoperative fluoroscopy can be recommended. Furthermore, the results indicate Schöttle's method as a reliable method for intraoperative control and postoperative analysis of femoral tunnel positioning.
  
  
  METHODS
  IV.
authors.affiliation: Department of Trauma and Orthopaedic Surgery, Cologne Merheim Medical Centre, Witten/Herdecke University, Ostmerheimer Strasse 200, 51109, Cologne, Germany.
authors.forename: Vera
authors.initials: V
authors.lastname: Jaecker
authors.affiliation: Department of Trauma and Orthopaedic Surgery, Cologne Merheim Medical Centre, Witten/Herdecke University, Ostmerheimer Strasse 200, 51109, Cologne, Germany.
authors.forename: Benedikt
authors.initials: B
authors.lastname: Brozat
authors.affiliation: Department of Trauma and Orthopaedic Surgery, Cologne Merheim Medical Centre, Witten/Herdecke University, Ostmerheimer Strasse 200, 51109, Cologne, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Banerjee
authors.affiliation: Department of Trauma and Orthopaedic Surgery, Cologne Merheim Medical Centre, Witten/Herdecke University, Ostmerheimer Strasse 200, 51109, Cologne, Germany.
authors.forename: Robin
authors.initials: R
authors.lastname: Otchwemah
authors.affiliation: Department of Trauma and Orthopaedic Surgery, Cologne Merheim Medical Centre, Witten/Herdecke University, Ostmerheimer Strasse 200, 51109, Cologne, Germany.
authors.forename: Bertil
authors.initials: B
authors.lastname: Bouillon
authors.affiliation: Department of Trauma and Orthopaedic Surgery, Cologne Merheim Medical Centre, Witten/Herdecke University, Ostmerheimer Strasse 200, 51109, Cologne, Germany. sven.shafizadeh@me.com.
authors.forename: Sven
authors.initials: S
authors.lastname: Shafizadeh
mesh_terms: D000293:Adolescent; D000328:Adult; D001182:Arthroscopy / Q000379:methods*; D002648:Child; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery*; D005471:Fluoroscopy; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000601:surgery*; D008023:Ligaments, Articular / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D057071:Patellofemoral Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D015641:Radiography, Interventional / Q000379:methods*; D013710:Tendons / Q000637:transplantation; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D055815:Young Adult
keywords: Graft positioning; MPFL; Medial patellofemoral ligament reconstruction; Patellofemoral instability; Precision; Tunnel positioning; Variability