Abstract
Novel cartilage regeneration therapies often look promising in-vitro but fail when implanted in vivo. One of the possible reasons for this discrepancy is the simplified, static in-vitro chondrogenesis models typically used. Complex mechanical stimulation plays a key role in physiological cartilage and chondrogenic cell metabolism, including the development of cartilage structure, yet it is routinely lacking during in-vitro studies. Multiaxial load bioreactors are becoming more widespread and offer advantages over more simple loading devices. Within this article, we highlight some of the important findings from in-vitro assays and key aspects relating to tribological loading of cartilage and chondrogenic cells.