New Polys and Large Heads: Clinical Aspects

摘要

Total hip replacement (THR) has become one of the most successful procedures in the last decades (Learmonth et al. 2007). Sir John Charnley developed low-friction arthroplasty using cemented fixation, a 22.225 mm stainless-steel femoral head and an all-polyethylene (PE) cup during the early 1960s of the last century, an operation with excellent long-term results worldwide (Charnley 1961) (Fig. 9.1). Cemented THRs usually show higher survivorship rates than uncemented designs; nevertheless some contemporary implants are providing very low rates of loosening with their improved primary and secondary bone fixation. In a study from the Swedish Hip Arthroplasty Register, Hailer et al. observed increased use of uncemented THR despite a lower revision rate at 10 and 15 years (Hailer et al. 2010). In their analysis they found better results for cemented arthroplasties regardless of the age or the diagnosis of the patient; when they assessed the cup and the stem, they concluded that the worse outcomes of uncemented THR were due to a higher revision rate of the cup produced by wear-related problems. So the most important problem in a long term is PE wear in both cemented and uncemented THRs as this is the main source of osteolysis and loosening (Harris 1995).