Autologous chondrocyte implantation (ACI) is a surgical procedure involving the injection of a person's own cultured joint cartilage cells back into a prepared defect in the cartilage.
The defect is cleaned up and then the chondrocytes are then injected behind a membrane that is sewn onto the defect
The two-stage procedure of ACI
This is known as a two-stage procedure, because the surgeon needs one procedure to harvest some healthy cartilage from a less important area and send the sample to a laboratory for culture (where they are multiplied and make many cells), and then there is a second procedure to implant the expanded cells into the damaged area to grow into healthy cartilage.
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