title: Tissue regeneration in orthopedic surgery - do we need cells?
abstract: BACKGROUND
  Tissue engineering has provided the orthopedic surgeon with a vast portfolio of methods for replacement or regeneration of articular cartilage or meniscal tissue. On the one hand cell based techniques such as autologous chondrocyte transplantation (ACT) are a main focus of interest. On the other hand cell free techniques are rapidly evolving and gaining more interest. The European Union regulation of November 2007, demanding proof of efficacy in cases of autologous cell transplantation, additionally increased the interest in cell-free techniques.
  
  
  OBJECTIVE
  The aim of this review was to discuss the advantages and disadvantages of cell-based and cell-free procedures and to summarize the clinical evidence for cell-free, tissue engineering procedures in orthopedic surgery for meniscal and cartilage defects.
  
  
  METHODS
  A systematic review was performed searching for clinical human studies evaluating cell-free repair procedures for cartilage and meniscus defects. All human study reports with English or German language abstracts were included.
  
  
  RESULTS
  The search revealed 82 studies of which only 12 met the inclusion criteria. Overall good clinical results for the use of cell-free meniscal and cartilage scaffolds were reported.
  
  
  CONCLUSIONS
  With improved understanding of the healing process in cartilage- and meniscal-defects, acellular, off the shelf products might gain more importance.
authors.forename: Karl F
authors.initials: KF
authors.lastname: Schüttler
authors.forename: Turgay
authors.initials: T
authors.lastname: Efe
mesh_terms: D002358:Cartilage, Articular / Q000601:surgery*; D002986:Clinical Trials as Topic; D006801:Humans; D008592:Menisci, Tibial / Q000601:surgery*; D019637:Orthopedic Procedures / Q000379:methods*; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
keywords: Tissue engineering; cartilage; cell-free; meniscus; repair; scaffold