Background: Charnley total hip arthroplasty
has been demonstrated to provide good clinical results and a high
rate of implant survivorship for twenty years and longer. Most long-term
series are not large enough to stratify the many demographic factors
that influence implant survivorship. The purpose of this study was to
analyze the effects of demographic factors and diagnoses on the
long-term survivorship of the acetabular and femoral components
used in Charnley total hip arthroplasty.
Methods: Two thousand primary Charnley total hip
arthroplasties (1689 patients) were performed at one institution
from 1969 to 1971. Patients were contacted at five-year intervals
after the arthroplasty. Twenty-five years after the surgery, 1228 patients
had died and 461 patients were living. Hips that had not had a reoperation,
revision or removal of a component for any reason, or revision or
removal for aseptic loosening were considered to have survived.
Survivorship data were calculated with use of the method of Kaplan
and Meier. Patients were stratified by age, gender, and underlying
diagnosis to determine the influence of these factors on implant
Results: The twenty-five year rates of survivorship
free of reoperation, free of revision or removal of the implant
for any reason, and free of revision or removal for aseptic loosening
were 77.5%, 80.9% and 86.5%, respectively.
The twenty-five-year survivorship free of revision for aseptic loosening
was poorer for each decade earlier in life at which the procedure
was performed; this survivorship ranged from 68.7% for
patients who were less than forty years of age to 100% for
patients who were eighty years of age or older. Men had a twofold
higher rate of revision for aseptic loosening than did women.
Conclusions: Age, gender, and underlying diagnosis
all affected the likelihood of long-term survivorship of the acetabular
and femoral components used in Charnley total hip arthroplasty.