Factors Associated with Early Loosening of Cemented Total Hip Prostheses

Abstract

Patient data and radiograms from a series of 237 consecutive total hip replacements were evaluated by means of a computer program in an attempt to study factors correlated with early loosening. The loosening rate was significantly influenced by several factors. The CAD prosthesis (Computer Assisted Design, Howmedica) was superior to the Charnley-Mueller-prosthesis. Cement viscosity seemed to be an important factor in that low viscosity was positively correlated to loosening; high viscosity showed a negative correlation. Several technical details in the performance of the operations and loosening correlated with the surgeon. Males who preoperatively had fairly unrestricted physical activity and high body weight were more prone to early loosening. No correlation was found with the diagnosis, previous hip surgery, age, osteoporosis or cortisone treatment preoperatively. A thorough technique is important. Total hip replacement should be performed by specialized surgeons.