Basic fibroblast growth factor (bFGF) in the synovial-like membrane around loose total hip prostheses.

The aim of this investigation was to examine the eventual presence of bFGF in the synovial-like membrane of the interface and pseudocapsular tissue of loose total hip replacement (THR) and compare it to control knee synovial membrane. bFGF was demonstrated using specific antibodies in avidin-biotin-peroxidase complex (ABC) staining and quantitated using a semiautomatic VIDAS image analysis system. bFGF was found in fibroblasts, in vascular endothelial cells and in particular in macrophages in a characteristic pattern. The number of bFGF positive cells per one mm2 was increased in interface (1693 +/- 291; n = 10; p < 0.01) and pseudocapsular tissue (1954 +/- 256; n = 10; p < 0.01), compared to the knee joint synovial membrane (1009 +/- 133; n = 10). These findings suggest that bFGF is involved in the enhanced tissue remodelling of the synovial-like membrane around loose total hip prostheses. Codistribution of metallosis and bFGF positive macrophages suggests a chronic foreign body type reaction as the driving stimulus.