title: Revision surgery after third generation autologous chondrocyte implantation in the knee.
abstract: OBJECTIVE
  Third generation autologous chondrocyte implantation (ACI) is an established treatment for full thickness cartilage defects in the knee joint. However, little is known about cases when revision surgery is needed. The aim of the present study is to investigate the complication rates and the main reasons for revision surgery after third generation autologous chondrocyte implantation in the knee joint. It is of particular interest to examine in which cases revision surgery is needed and in which cases a "wait and see" strategy should be used.
  
  
  METHODS
  A total of 143 consecutive patients with 171 cartilage defects were included in this study with a minimum follow-up of two years. All defects were treated with third generation ACI (NOVACART®3D). Clinical evaluation was carried out after six months, followed by an annual evaluation using the International Knee Documentation Committee (IKDC) subjective score and the visual analogue scale (VAS) for rest and during activity. Revision surgery was documented.
  
  
  RESULTS
  The revision rate was 23.4 % (n = 36). The following major reasons for revision surgery were found in our study: symptomatic bone marrow edema (8.3 %, n = 3), arthrofibrosis (22.2 %, n = 8) and partial graft cartilage deficiency (47.2 %, n = 17). The following revision surgery was performed: retrograde drilling combined with Iloprost infusion therapy for bone marrow oedema (8.4 %, n = 3), arthroscopic arthrolysis of the suprapatellar recess (22.2 %, n = 8) and microfracturing/antegrade drilling (47.3 %, n = 17). Significant improvements of clinical scores after revision surgery were observed.
  
  
  CONCLUSIONS
  Revision surgery after third generation autologous chondrocyte implantation is common and is needed primarily in cases with arthrofibrosis, partial graft cartilage deficiency and symptomatic bone marrow oedema resulting in a significantly better clinical outcome.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Niethammer
authors.affiliation: Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University Hospital of Munich (LMU), Munich, Germany, thomas.niethammer@med.uni-muenchen.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Niethammer
authors.forename: Siegfried
authors.initials: S
authors.lastname: Valentin
authors.forename: Andreas
authors.initials: A
authors.lastname: Ficklscherer
authors.forename: Mehmet F
authors.initials: MF
authors.lastname: Gülecyüz
authors.forename: Mehmet
authors.initials: M
authors.lastname: Gülecyüz
authors.forename: Matthias F
authors.initials: MF
authors.lastname: Pietschmann
authors.forename: Matthias
authors.initials: M
authors.lastname: Pietschmann
authors.forename: Peter E
authors.initials: PE
authors.lastname: Müller
authors.forename: Peter
authors.initials: P
authors.lastname: Müller
mesh_terms: D000328:Adult; D000368:Aged; D002358:Cartilage, Articular / Q000293:injuries* / Q000601:surgery*; D019902:Chondrocytes / Q000637:transplantation*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D010147:Pain Measurement; D012086:Reoperation; D014182:Transplantation, Autologous; D057832:Watchful Waiting