Clinical outcome and subchondral bone edema presence at two-year follow-up after high density autologous chondrocyte implantation treatment in the knee.

BACKGROUND

Recently, a new approach of autologous chondrocyte implantation technique (using as biomaterial a collagen type i/iii membrane) based on increasing cell density called HD-ACI (High Density Autologous Chondrocyte Implantation) has been described. The objective of this paper was to study the clinical outcome and incidence of subchondral bone oedema in patients with cartilage lesions in the knee treated with HD-ACI at 1-2 years of follow-up.

METHODS

This is a retrospective study performed with forty patients with chondral injuries grade iii-iv. All patients were treated with HD-ACI with a cellular dose of 5×106 chondrocytes /cm2 of lesion. The subjective perception of improvement of symptoms and functionality was measured with the IKDC score (International Knee Documentation Committee). The presence of bone oedema was assessed at 6, 12 and 24 months of follow-up by magnetic resonance imaging.

RESULTS

IKDC values showed a significant improvement at 12 and 24 months (P<.001). The mean difference of IKDC between the baseline visit and 12 months was 26.3 points, and 31.6 points at 24 months. Twenty-seven point five percent of the patients presented subchondral bone oedema at 2 years of follow-up.

CONCLUSIONS

HD-ACI is an effective and safe treatment that improves pain, clinical perception and functionality of the joint. No correlation was found between the presence of bone oedema and the patients' clinical outcome.