Article

In a previous study based on the Finnish Arthroplasty
Register, the survival of cementless stems was better than that of cemented stems
in younger patients. However, the survival of cementless cups was poor due to
osteolysis. In the present study, we analyzed population-based survival rates of
the cemented and cementless total hip replacements in patients under the age of
55 years with primary osteoarthritis in Finland. PATIENTS AND METHODS: 3,668
implants fulfilled our inclusion criteria. The previous data included years
1980-2001, whereas the current study includes years 1987-2006. The implants were
classified in 3 groups: (1) implants with a cementless, straight, proximally
circumferentially porous-coated stem and a porous-coated press-fit cup
(cementless group 1); (2) implants with a cementless, anatomic, proximally
circumferentially porous-coated stem, with or without hydroxyapatite, and a
porous-coated press-fit cup with or without hydroxyapatite (cementless group 2);
and (3) a cemented stem combined with a cemented all-polyethylene cup (the
cemented group). Analyses were performed separately for 2 time periods: those
operated 1987-1996 and those operated 1997-2006. RESULTS: The 15-year survival
for any reason of cementless total hip replacement (THR) group 1 operated on
1987-1996 (62%; 95% CI: 57-67) and cementless group 2 (58%; CI: 52-66) operated
on during the same time period was worse than that of cemented THRs (71%; CI:
62-80), although the difference was not statistically significant. The revision
risk for aseptic loosening of cementless stem group 1 operated on 1987-1996
(0.49; CI: 0.32-0.74) was lower than that for aseptic loosening of cemented stems
(p = 0.001). INTERPRETATION: Excessive wear of the polyethylene liner resulted in
numerous revisions of modular cementless cups. The outcomes of total hip
arthroplasty appear to have been relatively unsatisfactory for younger patients
in Finland.

Langue : ANGLAIS