engleski

Single nucelotid polymorphisms in genes for interleukin 6 (Il6) and transforming growth factor beta 1 (TGF-β 1) in patients with aseptic instability of the acetabular and femoral part of total hip arthroplasty - a pilot study.

Aseptic loosening is the main complication of the total hip arthroplasty that requires corrective surgery. The instability primarily affects the acetabular part and less frequently also the femoral part of the prosthesis, which requires that the entire prosthesis is replaced. We previously demonstrated association between single nucleotide polymorphisms in the signal sequence of the gene encoding for TGF-b1 (29T® A) and in the promotor region of the gene encoding for IL-6 (-597 G® A and -572 G® C) and the risk of aseptic instability after total hip arthroplasty. In the present preliminary analysis we aim to investigate potential association between a more severe form of the aseptic instability, i.e., the one that affects both the acetabular and the femoral part, and the genotypes at these polymorphic loci. The analysis included 29 patients (7 men, 22 women) with a total of 31 total hip arthroplasties (all of the same type, placed by the same surgeon), in whom aseptic instability has been evidenced during regular follow-up (to up to 20 years post arthroplasty) and who gave an informed consent for genotyping. Aseptic instability of only the acetabular cup was recorded in 15 cases and instability of both the acetabular cup and the femoral stem was recorded in 16 cases. No relevant differences were observed between the two groups regarding sex, age and body mass index at arthroplasty, or regarding the acetabular inclination angle achieved at arthroplasty or regarding the underlying morbidity. There was a statistically borderline significant trend (P=0.081) of a greater incidence of aseptic instability that affected also the femoral stem in patients with the transition homozygous genotype (C/C) at position -572 in the IL-6 promotor region. In respect to other possible genotypes at this position (G/G or G/C cumulatively), genotype C/C was associated with a statistically borderline significant (P=0.071) greater risk of aseptic instability that affected also the femoral part (risk ratio 1.90, 95% confidence interval 0.84- 3.68). The results support the need for further studies on this topic.

transforming growth factor beta 1 ; interleukin 6 ; single nucelotid polymorphisms ; arthroplasty ; hip ; loosening

nije evidentirano