We previously reported that perlecan, a heparan-sulfate proteoglycan (Hspg2), expressed in the synovium at the cartilage-synovial junction, is required for osteophyte formation in knee osteoarthritis.
Previously, we demonstrated that HS is markedly diminished in the exostosis cartilage cap and that the HS proteoglycan, perlecan, has an abnormal distribution in these caps.