title: Cartilage repair of experimentally 11 induced osteochondral defects in New Zealand White rabbits.
abstract: Articular cartilage has a limited capacity for self-repair in adult humans, and methods used to stimulate regeneration often result in re-growth of fibrous cartilage, which has lower durability. No current treatment option can provide complete repair. The possibility of growth factor delivery into the joint for cartilage regeneration after injury would be an attractive treatment option. A full thickness osteochondral defect of 4 mm in diameter and 2 mm deep was created by mechanical drilling in the medial femoral condyle in 20 female adult New Zealand White rabbits. In an attempt to improve regeneration a hyaluronic hydrogel system, with or without bone morphogenetic protein-2 (BMP-2) was delivered intraarticularly. The contralateral joint defect was treated with saline as control. Throughout the study, rabbits were clinically examined and after 12 (n = 6) or 24 (n = 9) weeks, the rabbits were euthanized and the joints evaluated by histology. The defects healed with fibrocartilage like tissue, and the filling of the defects ranged from less than 25% to complete. The healing of the defects varied both inter- and intra-group wise. Treatment with hyaluronan gel with or without BMP-2 had no effect on cartilage regeneration compared with controls. Instead, severe ectopic bone formation was found in seven joints treated with BMP-2. In conclusion, the present study shows that neither treatment with hyaluronic gel alone, nor in combination with BMP-2, improves the healing of an induced cartilage defect in rabbits. It further shows that BMP-2 can induce ectopic bone formation, which severely affects the functionality of the joint.
authors: Department of Chemistry, Ångström Laboratory, Polymer Chemistry, Uppsala University, SE-751 21 Uppsala, Sweden.
authors: C
authors: C
authors: Aulin
authors: M
authors: M
authors: Jensen-Waern
authors: S
authors: S
authors: Ekman
authors: M
authors: M
authors: Hägglund
authors: T
authors: T
authors: Engstrand
authors: J
authors: J
authors: Hilborn
authors: P
authors: P
authors: Hedenqvist
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage / Q000627:therapeutic use; D002358:Cartilage, Articular / Q000187:drug effects / Q000293:injuries / Q000473:pathology* / Q000601:surgery; D005260:Female; D005269:Femur / Q000473:pathology; D048091:Guided Tissue Regeneration / Q000379:methods*; D006820:Hyaluronic Acid / Q000627:therapeutic use; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000627:therapeutic use; D011817:Rabbits
chemical_list: D055396:Bone Morphogenetic Protein 2; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D006820:Hyaluronic Acid