TABLE 1.

Comparison of cartilage defect treatments widely used in clinics.

Treatment	Defect Area	Disadvantages
MF	<2 cm2	Regenerated cartilage is mainly composed of fibrous cartilage
ACI	>2 cm2	Two operations required, limitations in donor site, frequent donor site complications, uneven cellular distribution in receptor site, frequent cellular loss, unstable cellular phenotypes
Autologous cartilage transplantation	<4 cm2	Limitations in donor site, donor site complications, graft is not matched to the defect
Allogeneic cartilage transplantation	>4 cm2	Requirement to sustain chondrocyte viability, high standard donor age and challenges in preserving grafts