Surface exposure of human cadaveric cartilage to a therapeutic dose of colloidal 90Y decreased chondrocyte viability, expressed as the viable/non-viable pixel ratio, in the early post-irradiation period. The findings established in the ex-vivo simulation may reflect the changes in knee cartilage occurring after RSV therapy.

Prophylactic substitution treatment and radiosynoviorthosis have a leading role in preventing irreversible haemophilic arthropathy. The aim of the study was to evaluate the effects of prophylaxis treatment and radiosynovectomy on the length of intervals between subsequent haemorrhages in haemophilic patients. Thirty-three joints were treated with radiosynovectomy in 28 patients with bleeding disorders. (90)Y colloid was used in knees and (186)Re colloid for elbows, shoulders and ankles. Twenty patients were on prophylaxis. Joint X-rays were evaluated on the Pettersson scale between 0 (normal) and 13 (severe joint destruction). During an observation period (range 6-44 months) bleeding episodes were recorded and data statistically analysed. Before radiosynovectomy, increasing intensity of the prophylaxis 10% lengthens intervals between two haemorrhages by 1% (P < 0.05). In patients with a Pettersson score higher than nine, intervals between bleedings are shorter by 73% (P < 0.05), in comparison with patients with lower Pettersson scores of 0-5. After radiosynovectomy, the length of the first non-bleeding interval increased by 120% (to 60 days) in comparison with the intervals before the procedure (P < 0.001). But, in the following year and half, every subsequent non-bleeding interval was 8% shorter (P < 0.1). In that period, prophylaxis shortened the non-bleeding interval by 1.7% (P < 0.05) per 10% increase of its intensity. Radiosynovectomy is more efficient in patients with less affected joints and is less efficient in younger patients. Prophylaxis reduced time between the bleedings episodes after isotope application. Before radiosynovectomy, prophylaxis reduces the number of haemorrhages. Our findings support data previously published by Rodriguez-Merchan et al. [J Thromb Haemost, 5 (2007) P-W-126].