Abstract
INTRODUCTION
Fresh bipolar shell osteochondral allograft (FBOA) is a controversial treatment option for post-traumatic ankle arthritis. Immunological response to transplanted cartilage may play a role in failure. Aim of the study is to compare two groups of patients who received FBOA in association or not to immunosuppressive therapy.
METHODS
2 groups, of 20 patients each, underwent FBOA. Only one group (group-B) received immunosuppressive therapy. Pre-operative and follow-up evaluation were clinical (AOFAS) and radiographical (X-Rays, CT- scan, MRI). Bioptic samples harvested during II look were examined by histochemical, immunohistochemical (ICRS II score) and by genetic typing analyses.
RESULTS
Group-A pre-operative AOFAS score improved from 28.2 ± 10.9, to 69.9 ± 18.2 at 24 months follow-up(p<0.005), while Group B improved from 26.2 ± 6.8 to 71.4 ± 7.3 (p<0.005). Comparison of clinical outcomes between the groups was non-significant. Group B showed better morphology of the grafts (ICRS II score mean of 68%) compared to Group A (mean of 40%) (p<0.05). Genetic typing showed a mixed recipient/donor DNA presence. Kendall ordinal correlation between groups and ICRS score was found. All the samples rated as 100 were in group B, while all the samples rated 0 were in group A (=0.506, p=0.008).
CONCLUSIONS
Although clinical results were comparable in the two groups, better histological score in Group B evidentiated hyaline cartilage significatively better preserved. Genetic typing showed the presence of cells of the host into the transplanted cartilage suggesting a possible colonization of transplanted cartilage by host cells never described before.
