Review of Brittberg's article on the treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation: "The Classic".

Abstract

This Classic discusses the original publication by Brittberg and colleagues "Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation" [1], published in 1994 in the New England Journal of Medicine. At that time, this paper provided fresh, clinically relevant data on autologous chondrocyte transplantation (ACT) or, as it is commonly known today, autologous chondrocyte implantation (ACI) in the treatment of 23 patients with a symptomatic full-thickness articular cartilage defect of a femoral condyle or of a patellar facet. This was the first description of ACI being used in humans to heal articular cartilage defects. The clinical outcomes were good-to-excellent for 14 of the 16 patients with a femoral condylar defect and for two of the seven patients with a patellar defect, and these findings have largely been confirmed by subsequent research work. Nowadays, ACI has become a worldwide well-established surgical technique that has revolutionized the management of articular cartilage injuries. This is particularly relevant for young, high-demand patients, for whom reparative techniques like microfractures do not usually provide sufficient durability of treatment nor highly functional outcomes [2-3], leading to the development of early knee osteoarthritis (OA). Since this publication, which was more than 30 years ago, there has been a remarkable increase in the number of basic science and of clinical papers released on the topic. Thus, the present review starts by providing a detailed synopsis of this Classic and by highlighting its main take-home messages. Next, it discusses the historical perspectives, the scientific and the societal impact, the current evidence, and the lessons that we have learned so far. Lastly, it presents the state of ACI in 2025 and makes recommendations on its application for selected cases of full-thickness articular cartilage lesions in the knee based on the latest data that are available in the literature.