title: Matrix-associated autologous chondrocyte transplantation in a compartmentalized early stage of osteoarthritis.
abstract: OBJECTIVE
  Cartilage restoration in joints with an early stage of osteoarthritis (OA) is an important clinical challenge. In this study, a compartmentalized, early-stage OA was generated surgically in sheep stifle joints, and this model was used to evaluate a matrix-associated cell transplantation approach for cartilage repair.
  
  
  METHODS
  Eighteen sheep were operated twice. During the first operation, a unicompartmental OA in a stable joint was induced by creating a critical-size defect. The second operation served as a regeneration procedure. The eighteen sheep were divided into three groups. One group was treated with spongialization (SPONGIO), while the two others had spongialization followed by implantation of a hyaluronan matrix with (MACT) or without chondrocytes (MATRIX). The follow-up took place 4 months after the second operation. Gross Assessment of Joint Changes score and Brittberg score were used for the macroscopic evaluation, Mankin score, O'Driscoll score, and immunohistochemistry for collagen type I and type II for histological evaluation.
  
  
  RESULTS
  The MACT group achieved significantly better results in both macroscopic and histological examinations. In the regeneration area, a Mankin score of 7.88 (6.20; 9.55) [mean (upper 95% confidence interval; lower 95% confidence interval)] was reached in the MACT group, 10.38 (8.03; 12.72) in the MATRIX group, and 10.33 (8.80; 11.87) in the SPONGIO group. The O'Driscoll score revealed a highly significant difference in the degree of defect repair: 15.92 (14.58; 17.25) for the MACT group compared to the two other groups [5.04 (1.21; 8.87) MATRIX and 6.58 (5.17; 8.00) SPONGIO; P < 0.0001].
  
  
  CONCLUSIONS
  This study demonstrates promising results toward the development of a biological regeneration technique for early-stage OA.
authors.affiliation: Department of Orthopedic Surgery, Medical University of Vienna, Austria. mschinha@bidmc.harvard.edu
authors.forename: M
authors.initials: M
authors.lastname: Schinhan
authors.forename: M
authors.initials: M
authors.lastname: Gruber
authors.forename: R
authors.initials: R
authors.lastname: Dorotka
authors.forename: M
authors.initials: M
authors.lastname: Pilz
authors.forename: D
authors.initials: D
authors.lastname: Stelzeneder
authors.forename: C
authors.initials: C
authors.lastname: Chiari
authors.forename: N
authors.initials: N
authors.lastname: Rössler
authors.forename: R
authors.initials: R
authors.lastname: Windhager
authors.forename: S
authors.initials: S
authors.lastname: Nehrer
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental; D002358:Cartilage, Articular / Q000473:pathology / Q000601:surgery*; D017690:Cell Transplantation / Q000379:methods*; D019902:Chondrocytes / Q000637:transplantation*; D024042:Collagen Type I / Q000378:metabolism; D024043:Collagen Type II / Q000378:metabolism; D005260:Female; D006820:Hyaluronic Acid / Q000627:therapeutic use; D020370:Osteoarthritis, Knee / Q000473:pathology / Q000601:surgery*; D012756:Sheep; D013264:Stifle / Q000601:surgery; D014182:Transplantation, Autologous / Q000379:methods; D016896:Treatment Outcome; D055675:Viscosupplements / Q000627:therapeutic use
chemical_list: D024042:Collagen Type I; D024043:Collagen Type II; D055675:Viscosupplements; D006820:Hyaluronic Acid