This Level I RCT — the first to directly compare ACI and microfracture — enrolled 80 patients with a single full-thickness femoral condyle defect in a stable knee. Clinical outcomes were assessed at 12 and 24 months using Lysholm, SF-36, and VAS scores. A blinded histological biopsy was performed at two years to assess repair tissue quality.
When a young active patient comes in with an isolated femoral condyle defect under 4 cm² in a stable knee, this paper is the reason microfracture is a defensible — and by some measures superior. First-line choice at two years.
For defects under 4 cm², microfracture achieves equivalent Lysholm and pain scores to ACI while showing better SF-36 physical function, requiring one operation instead of two, and carrying a significantly lower reoperation burden (10% vs 25%). Reserve ACI for larger or noncontained defects, or after microfracture failure. The authors explicitly state this is where ACI may offer advantage.
The histology-to-function dissociation is the most important conceptual finding here: you cannot justify a more invasive procedure by pointing to biopsy results, because better-looking repair tissue at two years does not translate to better clinical scores.
This Level I RCT — the first to directly compare ACI and microfracture — enrolled 80 patients with a single full-thickness femoral condyle defect in a stable knee. Clinical outcomes were assessed at 12 and 24 months using Lysholm, SF-36, and VAS scores. A blinded histological biopsy was performed at two years to assess repair tissue quality.
When a young active patient comes in with an isolated femoral condyle defect under 4 cm² in a stable knee, this paper is the reason microfracture is a defensible — and by some measures superior. First-line choice at two years.
For defects under 4 cm², microfracture achieves equivalent Lysholm and pain scores to ACI while showing better SF-36 physical function, requiring one operation instead of two, and carrying a significantly lower reoperation burden (10% vs 25%). Reserve ACI for larger or noncontained defects, or after microfracture failure. The authors explicitly state this is where ACI may offer advantage.
The histology-to-function dissociation is the most important conceptual finding here: you cannot justify a more invasive procedure by pointing to biopsy results, because better-looking repair tissue at two years does not translate to better clinical scores.