This 1994 landmark case series by Brittberg et al. reports the first clinical use of autologous chondrocyte implantation (ACI) in humans. Twenty-three patients aged 14–48 with full-thickness knee cartilage defects (1.6–6.5 cm²) were treated and followed for a mean of 39 months. The paper asks whether cultured autologous chondrocytes can biologically restore articular cartilage — and whether outcomes differ by defect location.
Drilling and abrasion arthroplasty were the standard of care for cartilage defects before 1994, reliably producing fibrocartilage with type I collagen rather than the type II collagen–rich hyaline cartilage that normal joint function requires.
This paper established that cultured autologous chondrocytes can regenerate histologically confirmed hyaline-like cartilage in vivo — a finding that created the entire field of cell-based cartilage restoration.
When you evaluate a young patient with a large femoral condylar defect (greater than 2–4 cm²), this is why ACI (or its modern derivative, matrix-induced ACI) is on the table: marrow stimulation produces inferior tissue, and this paper is the original evidence.
For patellar defects, the lesson is equally important: only 28.6% of patellar patients had good or excellent results, and the authors attribute this to uncorrected malalignment and patellofemoral contact stress. Address the underlying mechanics. Malalignment, instability. Before or concurrent with any cartilage procedure on the patella.
This work directly enabled second- and third-generation ACI techniques (MACI, scaffold-based delivery) and remains the histologic benchmark against which all cartilage repair strategies are measured.
This 1994 landmark case series by Brittberg et al. reports the first clinical use of autologous chondrocyte implantation (ACI) in humans. Twenty-three patients aged 14–48 with full-thickness knee cartilage defects (1.6–6.5 cm²) were treated and followed for a mean of 39 months. The paper asks whether cultured autologous chondrocytes can biologically restore articular cartilage — and whether outcomes differ by defect location.
Drilling and abrasion arthroplasty were the standard of care for cartilage defects before 1994, reliably producing fibrocartilage with type I collagen rather than the type II collagen–rich hyaline cartilage that normal joint function requires.
This paper established that cultured autologous chondrocytes can regenerate histologically confirmed hyaline-like cartilage in vivo — a finding that created the entire field of cell-based cartilage restoration.
When you evaluate a young patient with a large femoral condylar defect (greater than 2–4 cm²), this is why ACI (or its modern derivative, matrix-induced ACI) is on the table: marrow stimulation produces inferior tissue, and this paper is the original evidence.
For patellar defects, the lesson is equally important: only 28.6% of patellar patients had good or excellent results, and the authors attribute this to uncorrected malalignment and patellofemoral contact stress. Address the underlying mechanics. Malalignment, instability. Before or concurrent with any cartilage procedure on the patella.
This work directly enabled second- and third-generation ACI techniques (MACI, scaffold-based delivery) and remains the histologic benchmark against which all cartilage repair strategies are measured.