RESUMEN
Objective: To analyze the cause of prosthesis loosening by observing the interface membranes harvested during the hip restoration operation. Methods: A total of 28 specimens of interface membrane around the loose prosthesis were harvested from 28 patients undergoing the restoration of total hip replacement. All the specimens underwent the observation of appearance, light microscopy and scanning electronic microscopy(SEM). Results: All the gaps around the loose prosthesis were filled with interface membrane of different thickness. The color of the most interface membrane was madder red, and the other one third of membrane was black. The comparatively thicker membrane was similar to scar connective tissue while the thinner was similar to fiber membrane. A large number of wear debris, macrophages and foreign-body giant cells were found under light microscope. With SEM observation a large number of different diameter collagen fibra structures that looked like scar tissues were arranged disorderly in a great mass, foreign particles and bone debris of different size were distributed unevenly, and the fibroblast was distributed in the collagen fiber. Conclusion: Wear debris is related to inflammatory cell response around the interface membrane of the loose prosthesis. The wear debris engulfed by macrophage stimulates the interface membrane to release bone resorption factors (such as TNF) which lead to osteolysis, and this is one of the most important causes of the prosthesis loosening.
RESUMEN
[Objective]To study the reason of loosening prothesis by observing the interface membranes harvested during the hip revision operation.[Method]Thirty eight specimens of interface membranes around the loosening prothesis were harvested from thirty eight patients who underwent the revision of total hip replacement.All the specimens were underwent outer observation,light and scanning electronic microscopic observation.[Result]All the gap of the loosening prothesis were filled with interface membranes with different thickness.A large number of the foreign pelletand bone pieces were found under scanning electronic microscope.[Conclusion]Interface membranes growed and filled in the gap between the loosening prothesis and bone(or bone cement).The wear debris stimulated the interface membrane to release bone resorption factors which caused the prothesis loosening,and the more loosening,the more large gap appeared,and the more resorption factors released from the interface membranes due to the debris stimulating,which formed vicious circle.Cutting the link of the circle could decrease the loosening rates.
RESUMEN
Objective Collecting the loosening periprosthetic interface-membrane, to discuss the mechanism of hip arthroplasty loosening. Methods The periprosthetic interface tissues of 29 hip arthroplasty revision cases from February 1995 to December 2003 were collected. The retrieved periprosthetic interface tissues were detected by immunohistochemistry. Some of them were studied by electronic microscope. Results (1)Transmission electronic microscope examination: the mitochondria swell. There were some substantia like lipid in the plasm of macrophages. Wear particles could be seen under scaning electronic microscope.(2)Immunohistochemistry: there were 22 IL-1? positive cases in cells of interface membrane. There were 29 IL-6 positive cases in cells of interface membrane. There were no positive results in TNF-? test. Conclusion (1)The wear particles of arthroplasty are important factors which cause biological reaction.(2)The interface membranes contain cytokine IL-1? and IL-6, which may play an important role in periprosthetic osteolysis and arthroplasty loosening.