title: An autologous cartilage tissue implant NeoCart for treatment of grade III chondral injury to the distal femur: prospective clinical safety trial at 2 years.
abstract: BACKGROUND
  The healing potential of damaged articular cartilage is limited. The NeoCart is a tissue-engineered collagen matrix seeded with autogenous chondrocytes designed for the repair of hyaline articular cartilage.
  
  
  OBJECTIVE
  The NeoCart implant is well tolerated in the human knee.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  Eight patients (treatment group) with full-thickness cartilage injury were treated with the NeoCart and evaluated prospectively. Autogenous chondrocytes provided by arthroscopic biopsy were seeded into a 3-dimensional type I collagen scaffold. The seeded scaffold was subjected to a tissue-engineering protocol including treatment with a bioreactor. Implantation of the prepared cartilage tissue patch was performed via miniarthrotomy and secured with a collagen bioadhesive. Evaluations through 24 months postoperatively included the subjective International Knee Documentation Committee questionnaire, visual analog scale, range of motion, and cartilage-sensitive magnetic resonance imaging (MRI), including quantitative T2 mapping.
  
  
  RESULTS
  Pain scores after NeoCart implantation were significantly lower than baseline at 12 and 24 months after the procedure (P < .05). Improved function and motion were also noted at 24 months. Six patients had 67% to 100% defect fill at 24 months with MRI evaluation. One patient had moderate (33%-66%) defect fill, and another patient had poor (less than 33%) defect fill. Partial stratification of T2 values was observed for 2 patients at 12 months and 4 patients at 24 months. No patients experienced arthrofibrosis or implant hypertrophy.
  
  
  CONCLUSIONS
  Pain was significantly reduced 12 and 24 months after NeoCart treatment. Trends toward improved function and motion were observed 24 months after implantation. The MRI indicated implant stability and peripheral integration, defect fill without overgrowth, progressive maturation, and more organized cartilage formation.
authors.affiliation: Department of Orthopaedics, Oregon Health and Science University, Portland, Oregon 97239, USA. crawfden@ohsu.edu
authors.forename: Dennis C
authors.initials: DC
authors.lastname: Crawford
authors.forename: Chelsea M
authors.initials: CM
authors.lastname: Heveran
authors.forename: W Dilworth
authors.initials: WD
authors.lastname: Cannon
authors.forename: Li Foong
authors.initials: LF
authors.lastname: Foo
authors.forename: Hollis G
authors.initials: HG
authors.lastname: Potter
mesh_terms: D000328:Adult; D002356:Cartilage / Q000637:transplantation*; D019902:Chondrocytes / Q000473:pathology*; D002986:Clinical Trials as Topic; D005260:Female; D005269:Femur / Q000293:injuries* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D016378:Tissue Transplantation / Q000009:adverse effects; D014182:Transplantation, Autologous / Q000534:rehabilitation