Osteophytes: relevance and biology

Objective: Osteophytes are common features of osteoarthritis. This review summarizes the current understanding of the clinical relevance and biology of osteophytes. Method. This review summarizes peer-reviewed articles published in the PubMed database before May 2006. In addition this review is supplemented with own data and theoretical considerations with regard to osteophyte formation. Results: Osteophytes can contribute both to the functional properties of affected joints and to clinical relevant symptoms. Osteophyte formation is highly associated with cartilage damage but osteophytes can develop without explicit cartilage damage. Osteophytes are mainly derived from precursor cells in the periosteum and growth factors of the TGF beta superfamily appear to play a crucial role in their induction. Conclusion. Osteophyte formation is an integral component of OA pathogenesis and understanding the biology of osteophyte formation can give insights in the disturbed homeostasis in OA joints. (C) 2006 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.