title: Complications of medial patellofemoral ligament reconstruction using two transverse patellar tunnels.
abstract: OBJECTIVE
  The aim of this study was to report the complication rate after a medial patellofemoral ligament (MPFL) reconstruction using transverse patellar tunnels in a retrospective case series performed in a single institution.
  
  
  METHODS
  Case series of 179 patients (192 knees) that had an MPFL reconstruction, with or without additional bony realignment procedures, between January 2009 and March 2015. Data were obtained from available patient charts.
  
  
  RESULTS
  Thirty-nine complications (20.3 %) were registered. Twenty-seven of these (14.7 %) were minor. Seven patients (3.6 %) sustained a patellar fracture without adequate trauma. Male gender was a risk factor for patellar fracture (p < 0.001). Sixteen (8.1 %) reported recurrence of instability, of whom 10 (5.1 %) were defined as objective instability (reported dislocation and positive apprehension test).
  
  
  CONCLUSIONS
  This is largest patient series to date in which the complications after a two tunnel MPFL reconstruction are described. The use of transverse patellar tunnels increases the risk of sustaining a patellar fracture.
  
  
  METHODS
  IV.
authors.affiliation: Department of Orthopedic Surgery, Canisius-Wilhelmina Ziekenhuis, PO Box 9015, 6500 GS, Nijmegen, The Netherlands. loes.schiphouwer@gmail.com.
authors.forename: Loes
authors.identifier: http://orcid.org/0000-0001-8327-9358
authors.initials: L
authors.lastname: Schiphouwer
authors.affiliation: Department of Orthopedic Surgery, Canisius-Wilhelmina Ziekenhuis, PO Box 9015, 6500 GS, Nijmegen, The Netherlands.
authors.forename: Akkie
authors.initials: A
authors.lastname: Rood
authors.affiliation: Department of Orthopedic Surgery, Canisius-Wilhelmina Ziekenhuis, PO Box 9015, 6500 GS, Nijmegen, The Netherlands.
authors.forename: Siebren
authors.initials: S
authors.lastname: Tigchelaar
authors.affiliation: Department of Orthopedic Surgery, Canisius-Wilhelmina Ziekenhuis, PO Box 9015, 6500 GS, Nijmegen, The Netherlands.
authors.forename: Sander
authors.initials: S
authors.lastname: Koëter
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D050723:Fractures, Bone / Q000453:epidemiology; D000070632:Hamstring Tendons / Q000637:transplantation*; D006801:Humans; D007593:Joint Instability / Q000453:epidemiology; D007718:Knee Injuries / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010329:Patella / Q000293:injuries / Q000601:surgery*; D031222:Patellar Dislocation / Q000601:surgery*; D017847:Patellar Ligament / Q000293:injuries / Q000601:surgery*; D057071:Patellofemoral Joint / Q000293:injuries / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology*; D019651:Plastic Surgery Procedures / Q000379:methods*; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D055815:Young Adult
keywords: Complications; MPFL; MPFL reconstruction; Medial patellofemoral ligament; Patellar instability