[Longterm results of poldi hip replacement.]

The authors evaluated 124 patients operated on by means of cemented Poldi THR in the period 1980-1986 on average 14,2 years after the primary implantation (12,2-18,0). Average age of patients was 55 years (in the range of 33 to 75). Pre-operative diagnosis was osteoarthritis in 78 cases and rheumatoid arthritis in 46 patients. All patients had normal anatomical relations. The implants applied included a 49 mm polyethylene cup and a bananashaped CoCr polished stem with 32 mm head with the use of 1st generation method of cementing. Harris Hip Score averaged prior to the surgery 49 (19-52) and after the surgery 68 (49-98). In 59 patients Harris Hip Score was above 70 points. In total, 10 revision surgeries were performed of which 9 due to aseptic loosening (the cup - 6times, the cup and the stem - twice, the stem - once) and 1 due to septic loosening. There were 23 cases of evident loosening of the cup (of which 8 symptomatic and 15 asymptomatic one) and 8 probable. The number of potential operations of the cup is 46 and that of the stem 11. Combined prevalence of revision surgeries accomplished and potential is 54 (43,5 %) in case of the cup and 14 (11,2 %) in case of the stem. The survival rate after 14 years is 81,5 % in the acetabular cup and 95,2 % in case of the stem. Authors found out an increased number of THR failure after 12 years due to aseptic loosening of the acetabular cup. After the Kaplan-Maier curve the survival rate of THR after 4 years is 99 %, after 8 years 97 %, after 10 years 94 %, after 12 years 91 % and after 15 years 76 %. Linear polyethylene wear of the cup is on average 0,14 mm annually, and the volumetric one amounts to 189 cubic mm annually. Key words: THR, longterm results.