Hip disease and the prognosis of total hip replacements - A review of 53 698 primary total hip replacements reported to the Norwegian Arthroplasty Register 1987-99

We studied the rates of revision for 53 698 VV primary total hip replacemen ts (THRs) in nine different groups of disease. Factors which have previousl y been shown to be associated with increased risk of revision, such as male gender, young age, or certain types of uncemented prosthesis, showed impor tant differences between the diagnostic groups, Without adjustment for thes e factors we observed an increased risk of revision in patients with paedia tric hip diseases and in a small heterogeneous 'other' group, compared with patients with primary osteoarthritis, Most differences were reduced or dis appeared when an adjustment for the prognostic factors was made. After adju stment, an increased relative risk (RR) of revision compared with primary o steoarthritis was seen in hips with complications after fracture of the fem oral neck (RR = 1.3, p = 0.0005), in hips with congenital dislocation (RR = 1.3, p = 0.03), and in the heterogenous 'other' group, The analyses were a lso undertaken in a more homogenous subgroup of 16 217 patients which had a Charnley prosthesis implanted with high-viscosity cement. The only differe nce in this group was an increased risk for revision in patients who had un dergone THR for complications after fracture of the femoral neck (RR = 1.5, p = 0.0005), THR for diagnoses seen mainly among young patients had a good prognosis, bu t they had more often received inferior uncemented implants. If a cemented Charnley prosthesis is used, the type of disease leading to THR seems in mo st cases to have only a minor influence on the survival of the prosthesis.