A Randomized Multicenter Trial Comparing Autologous Chondrocyte Implantation with Microfracture: Long-Term Follow-up at 14 to 15 Years

Knutsen G, Drogset JO, Engebretsen L, et al. · The Journal of Bone and Joint Surgery. American Volume

No difference at 14-15 years: 17 ACI failures vs 13 microfracture; roughly half of survivors in both arms had radiographic early osteoarthritis. A major null result against first-generation ACI's superiority.

Population

80 patients from the Norwegian ACI-vs-microfracture RCT followed 14-15 years

Intervention

First-generation ACI

Comparator

Microfracture

Limitations

First-generation periosteal ACI, not modern MACI; modest n; both arms deteriorated.