Related Analysis Between The Interface Membrane And Loosening Prothesis For Bone Tumor

ObjectiveTo observe the microstructure and ultra-microstructure character of theinterface membranes around the prostheses of loosening prostheses for bonetumor and correlate the components wear debris particales and histologicalfindings of periprosthetic tissue.To explore the underlying mechanisms ofprostheses for bone tumor aseptic loosening,and the role of metal wear debrisplayed in tissue reactions of loosening prostheses for bone tumor was studied, inorder to support theoretical basis in clinical works.Methods10domestic made prostheses for bone tumor at the knee were retrievedfrom revision surgery and the periprosthetic tissues were collected.Thespecimens were observed under optical microscope after HE staining, and CD68expression in periprosthetic tissues were demonstrated by immunohistochemistrystaining.In order to confirm the presence of corrosion products, the specimens wereobserved and examined under scanning electron microscope(SEM),energydispersive X-ray (EDX) was used in some areaes of the interface membrane afterprepared. And pathological character of periprosthetic tissues wassemi—quantitively evaluated and was compared with EDX information of themetal wear debris wear character to analysis the underlying mechanisms ofprostheses for bone tumor aseptic loosening.All the data was processed by SPSS17.0Kendall’s tau b test in the software, P<0.05as statistically significant difference.ResultsAll the gap of the loosening prothesis were filled with interface membraneswith different thickness. Interface membrane consisted of fibromatrix, fibroblasts,leukomonocyte, and foreign body giant cells. And high expression of CD68cellswere demonstrated in periprosthetic interfacial tissues.MΦ[CD68positive,occupying24.5%±5%(x|-±s)], The number of CD68positive cells correlatedwell with the histological scores on chronic inflammation of periprosthetic tissues.Histological quantified score levels from8without ultra-high molecular weightpolyethylene cases were higher, as well as the the number of CD68positive cells,while more intense tissue reactions of periprosthetic tissue were revealed ofthese cases. Many kinds of globe and the anomalous shape particulate matter inthe tissue could be found by SEM assuming the disper_sed distribution, theirdiameters range from1μm to60μm. The elements of K, Na, Mg, Ca, Al, Ti, Fe, Si,Co, Cr could been seen by spectrum analysis. A conclusion could be made thatFe, Al, Ti, Si, Co, Cr are characteristic elements of interface membrance and theycould not been found in normal tissue. The pathology scores and the Ti weardebris ratios of interface membrane were lower in Titanium Alloy (Ti-6Al-4V) withultra-high molecular weight polyethylene patients compared with non-ultra-highmolecular weight polyethylene component (P<0.05). A positive association wasfound between Ti wear debris ratios and the number of CD68positive cells（r_s=0.778，P<0.01）. Furthermore, a positive correlation existed between the Tiwear debris ratios and the total pathology score（r_s=0.629，P<0.01）.ConclusionsTumor prostheses can give a satisfactory functional outcome, but the tumorprostheses have a higher complication rate about prostheses aseptic looseningthan the normal hip or knee prostheses because of it was used after wideresection.The forming of interface membrane in loosening prostheses for bone tumor isthe result of the body cells reacted to wear debris. The simultaneous presence of corrosion products and hypersensitivity-associated tissue reaction indicates thata relationship between exposure range and implant-related hypersensitivity mayexist. Metal wear particles in the interface membrane have relations withosteolysis and chronic inflammation of periprosthetic tissues, which plays animportant role in aseptic loosening.