Osteochondral tissue engineering: Perspectives for clinical application and preclinical development

Abstract

The treatment of osteochondral defects (OCD) remains challenging. Among currently available surgical treatments for OCDs, scaffold-based treatments are promising to regenerate the osteochondral unit. However, there is still no consensus regarding the clinical effectiveness of these scaffold-based therapies for OCDs. Previous reviews have described the gradient physiological characteristics of osteochondral tissue and gradient scaffold design for OCD, tissue engineering strategies, biomaterials, and fabrication technologies. However, the discussion on bridging the gap between the clinical need and preclinical research is still limited, on which we focus in the present review, providing an insight into what is currently lacking in tissue engineering methods that failed to yield satisfactory outcomes, and what is needed to further improve these techniques. Currently available surgical treatments for OCDs are firstly summarized, followed by a comprehensive review on experimental animal studies in recent 5 years on osteochondral tissue engineering. The review will then conclude with what is currently lacking in these animal studies and the recommendations that would help enlighten the community in developing more clinically relevant implants. The translational potential of this article This review is attempting to summarize the lessons from clinical and preclinical failures, providing an insight into what is currently lacking in TE methods that failed to yield satisfactory outcomes, and what is needed to further improve these implants.

3D gel-printed porous magnesium scaffold coated with dibasic calcium phosphate dihydrate for bone repair in vivo

“…First, a porous structure with a sufficient pore size to allow the exchange of bone cells, nutrients and metabolites. It is generally accepted that a pore size greater than 300 ​μm is suitable for the formation of blood vessels and new bone [ [37] , [38] , [39] , [40] ]. Second, there should be a surface that allows blood vessels to grow, bone cells to attach, migrate, and proliferate.…”

Seamless and early gap healing of osteochondral defects by autologous mosaicplasty combined with bioactive supramolecular nanofiber-enabled gelatin methacryloyl (BSN-GelMA) hydrogel

“…Autograft osteochondral transfer (AOT) mosaicplasty, one of the most extensively applied surgical techniques in clinical practice, involves transplantation of multiple small cylindrical autologous osteochondral units as plugs from less load-bearing sites to the defect sites [ [1] , [2] , [3] ]. The operation offers several advantages over other repair techniques such as primary repair, less incision and injury, lower cost, and quick recovery [ [4] , [5] , [6] , [7] ].…”

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