PREDICTION OF THE LONG-TERM DURABILITY OF ALL-POLYETHYLENE CEMENTED SOCKETS

A retrospective study was done to determine the correlation between th e rate of aseptic loosening and the early radiographic appearance of t he bone-cement interface of the acetabulum of primary cemented total h ip prostheses. Two hundred thirty-six hips implanted with modern cemen t technique were studied during an average clinical and radiographic f ollow up of 9 years. Early radiographs and the last available radiogra phs were studied by 3 independent observers, and the quality of the bo ne-cement interface was evaluated with a standardized scoring system. On the acetabular side, the authors noted 0.8% clinical failure, a 3% rate of radiographic migration, and a 3.4% rate of progressive global radiolucency. Only 2.2% of hips considered well fixed on the postopera tive film were loose. Of the hips considered not well fixed, the rate of aseptic loosening was 14.4%. The authors conclude that (1) the stat e of the bone-cement interface as seen on the early postoperative radi ograph can predict the longevity of a cemented socket with a high degr ee of probability, and that (2) cementation of an all-polyethylene soc ket using modern cement technique is an excellent method of fixation f or patients 60 years of age and older with degenerative joint disease.