title: Poly-L-D-lactic acid scaffold in the repair of porcine knee cartilage lesions.
abstract: Articular cartilage injuries cause a major clinical problem because of the negligible repair capacity of cartilage. Autologous chondrocyte transplantation is a surgical method developed to repair cartilage lesions. In the operation, cartilage defect is covered with a periosteal patch and the suspension of cultured autologous chondrocytes is injected into the lesion site. The method can form good repair tissue, but new techniques are needed to make the operation easier and to increase the postoperative biomechanical properties of the repair tissue. In this study, we investigated poly-L,D-lactic acid (PLDLA) scaffolds alone or seeded with autologous chondrocytes in the repair of circular 6-mm cartilage lesions in immature porcine knee joints. Spontaneous repair was used as a reference. Histologic evaluation of the repair tissue showed that spontaneous repair exhibited higher scores than either PLDLA scaffold group (with or without seeded chondrocytes). The scaffold material was most often seen embedded in the subchondral bone underneath the defect area, probably because of the hardness of the PLDLA material. However, some of the cell-seeded and nonseeded scaffolds contained cartilaginous tissue, suggesting that invasion of mesenchymal cells inside nonseeded scaffolds had occurred. Hyaluronan deposited in the scaffold had possibly acted as a chemoattractant for the cell recruitment. In conclusion, the PLDLA scaffold material used in this study was obviously mechanically too hard to be used for cartilage repair in immature animals.
authors.affiliation: Department of Anatomy, Institute of Biomedicine, University of Kuopio, Kuopio, Finland.
authors.forename: Outi
authors.initials: O
authors.lastname: Pulliainen
authors.forename: Anna I
authors.initials: AI
authors.lastname: Vasara
authors.forename: Mika M
authors.initials: MM
authors.lastname: Hyttinen
authors.forename: Virpi
authors.initials: V
authors.lastname: Tiitu
authors.forename: Piia
authors.initials: P
authors.lastname: Valonen
authors.forename: Minna
authors.initials: M
authors.lastname: Kellomäki
authors.forename: Jukka S
authors.initials: JS
authors.lastname: Jurvelin
authors.forename: Lars
authors.initials: L
authors.lastname: Peterson
authors.forename: Anders
authors.initials: A
authors.lastname: Lindahl
authors.forename: Ilkka
authors.initials: I
authors.lastname: Kiviranta
authors.forename: Mikko J
authors.initials: MJ
authors.lastname: Lammi
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D019902:Chondrocytes / Q000473:pathology* / Q000637:transplantation*; D050724:Fractures, Cartilage / Q000473:pathology* / Q000601:surgery*; D048091:Guided Tissue Regeneration / Q000379:methods*; D007718:Knee Injuries / Q000473:pathology / Q000601:surgery; D019344:Lactic Acid / Q000737:chemistry* / Q000627:therapeutic use; D011091:Polyesters; D011108:Polymers / Q000737:chemistry* / Q000627:therapeutic use; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)