Induction of Spontaneous Hyaline Cartilage Regeneration Using a Double-Network Gel Efficacy of a Novel Therapeutic Strategy for an Articular Cartilage Defect

Background: A double-network (DN) gel, which was composed of poly-(2-acrylamido-2-methylpropanesulfonic acid) and poly-(N,N′-dimetyl acrylamide) (PAMPS/PDMAAm), has the potential to induce chondrogenesis both in vitro and in vivo.Purpose: To establish the efficacy of a therapeutic strategy for an articular cartilage defect using a DN gel.Study Design: Controlled laboratory study.Methods: A 4.3-mm-diameter osteochondral defect was created in rabbit trochlea. A DN gel plug was implanted into the defect of the right knee so that a defect 2 mm in depth remained after surgery. An untreated defect of the left knee provided control data. The osteochondral defects created were examined by histological and immunohistochemical evaluations, surface assessment using confocal laser scanning microscopy, and real-time polymerase chain reaction (PCR) analysis at 4 and 12 weeks. Samples were quantitatively evaluated with 2 scoring systems reported by Wayne et al and O’Driscoll et al.Results: The DN gel–implanted defect wa...