Osteolysis incidence

Vinyl chloride causes liver cancer (hemangiosarcoma), narcosis, and Raynaud s phenomenon that comprises scleroderma, acro-osteolysis, and liver damage. The appearance of liver tumors is dose dependent but reaches a maximum at about 22% incidence. This seems to be due to the fact that the metabolism that is necessary for the carcinogenicity, is saturated, and/or inhibited by vinyl chloride. The toxic metabolites produced are the epoxide and chloroacetaldehyde. 

The three main alternatives to conventional UHMWPE represent the current state of the art in orthopedics, and are all expected to result in significant reductions in osteolysis. The ultimate goal for all of these alternative bearings is to reduce the incidence of revision for THA. Many years of clinical follow-up are still needed to verify the attainment of fhis long-term objective. 

Incidence and Significance of Osteolysis in Total Knee Arthroplasty... 

Whether in the hip or the knee, for osteolysis to expand, wear debris particles need access to the periprosthetic bone. From review of the ortiiopedic knee literature, it appears that cemented fixation of knee components is an effective barrier to particle access, and explains the lower incidence of osteolysis in studies with cemented components (Table 8.3). In this regard, much of the knee... 

Study Prosthesis design Fixation Mean follow-up (years) Incidence of osteolysis in study population Osteolysis diagnosis Incidence of revisions for osteolysis... 

The incidence of osteolysis with cementless fixation has been reported as high as 30% within the first 5 years of implantation [47] (Table 8.3). In studies of cemented components, in contrast, the incidence of osteolysis is generally lower and has been reported to range between 0% and 20% (Table 8.3). In addition to the fixation method, implant factors (e.g., design [48-50]) and patient factors (e.g., obesity [51]) have been shown to have a significant influence on the incidence of osteolysis in TKA. 

In 1991, John Dumbleton, PhD, in charge of Howmedica Worldwide R D, wanted to focus on decreasing the incidence of osteolysis and look more closely at UHMWPE oxidation. He beheved measurement of wear needed to be more representative of chnical conditions and decided to focus one researcher on understanding of the stracture/property relationships ofUHMWPE and developing improved materials. 

The goal of using radiographic analysis techniques to measure wear in total hip arthroplasty has changed over time. Originally, they were used to correlate the amount of femoral head penetration with the incidence of periprosthetic osteolysis. This association is now well established and irrefutable. New bearing materials, such as... 

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