Aseptic loosening after total hip arthroplasty. Incidence, clinical significance, and etiology.

Three hundred forty-one consecutive Charnley total hip arthroplasties were reviewed after a 3-10-year follow-up period to correlate the radiographic signs of aseptic loosening to clinical outcome, femoral cementing technique, and epidemiologic patient characteristics. High-grade femoral demarcation at the bone-cement interface (75-100%) correlated with a significantly higher incidence of unsatisfactory follow-up clinical scores. The incidence of high-grade femoral bone-cement demarcation and the associated radiographic signs of aseptic loosening had a direct correlation with the quality of the femoral cementing technique (P less than .01). Trochanter nonunion or trochanter separation demonstrated a highly significant correlation with high-grade femoral bone-cement demarcation (P less than .001). Patients having secondary total hip arthroplasty for failed cup arthroplasty or endoprosthesis had a higher rate of unsatisfactory pain and function scores, compared with those having arthroplasties performed after failed internal fixation. Male patients or patients with a high activity level demonstrated a twofold greater incidence of high-grade femoral demarcation (P less than .05). Patient weight by itself did not demonstrate any effect on radiographic outcome.