Borderline indications for use of cement in total joint replacements.

: In order to delineate the borderline indications for the cemented and uncemented total hip replacements, we need to evaluate the existing success rates with these procedures. The long term success rates with cemented total hip replacements done using an intramedullary methylmethacrylate plug, doughy Simplex bone cement introduced in a retrograde fashion via a cement gun, and collared cobalt-chrome femoral components with rounded corners were reviewed at eleven year follow-up. The patients ranged in ages from 20 to 84 years (mean 57 years). Among the 105 patients in the group followed up at a minimum of 10 years 97% of the femoral components remained rigidly fixed. These results suggest that the cemented femoral components give satisfactory results to the vast majority of patients over eleven years. Further improvements in the use of cement for prosthetic fixation were made since then. The strength of the cement-prosthesis interface is now considerably enhanced by precoating the prosthesis industrially with a thin layer of methacrylate and or by using texture prosthesis. The strength of cement is considerably improved by techniques such as centrifuging the cement after mixing, or mixing the cement in vacuum. These techniques appear promising and may further enhance the fixation of the prostheses to the skeleton.