Polyethylenbeladung und Zellgröße von Fremdkörperriesenzellen bei der aseptischen Hüftendoprothesenlockerung - Eine histomorphometrische Untersuchung1

Introduction: In aseptic loosening of cementless hip arthroplasty polyethylene particles are phagocytized by macrophages and foreign-body giant cells. This initiates an osteolytic cascade. In this study, the authors investigated if there are correlations between the size of foreign-body giant cells and the polyethylene loading and number of intracellular particles as determined by light microscopy. Material and Method: Histological specimens were processed from tissues retrieved during revision surgery of 7 cases of cementless hip arthroplasty which had become aseptically loose. The specimens were analyzed by histolomorphology and histomorphometry. The cell size, polyethylene loading and intracellular particle number of 111 foreign-body giant cells were determined. A regression analysis was performed to investigate if there was a correlation between these variables. Results: The mean cell size was 1417 ± 487 μm 2 , the mean polyethylene loading was 49 ± 42 μm 2 and the mean intracellular particle number was 10.4 ± 5.4. The cell size correlated with both the intracellular particle number (r = 0.25) and the polyethylene loading (r = 0.39). Conclusions: In the cellular reaction to polyethylene particles in aseptic loosening of cementless total hip arthroplasty, the size of foreign-body giant cells correlates with intracellular polyethylene loading and intracellular polyethylene particle number as determined by light microseopy. The presence of large foreign body giant cells might be associated with a high particle load of the tissue and a high osteolytic activity.