Prostheses for primary total hip replacement. A critical appraisal of the literature

Eighty-one published papers on the performance of prostheses in total hip replacement were appraised. Sound methodology was demonstrated in 1 of 8 randomized controlled trials and 4 of 17 nonrandomized comparative studies. Of 56 case series without controls, 32 met the appraisal criteria, but these are intrinsically less useful. The published literature does not provide solid evidence for the superiority of cement-free or hybrid prostheses over modern cemented types.