Which Factors Associate With Implant Revision and Hip Disarticulation After Total Femur Replacement? A Retrospective...

Total femur replacements (TFRs) are rarely performed procedures in orthopaedic oncology and revision arthroplasty surgery. These procedures are associated with a high proportion of complications and revisions, most frequently because of infection. Revision risk and associated parameters in a high-risk population remain to be determined.

(1) What is the cumulative incidence of implant revision and hip disarticulation after TFR at 2 and 5 years after the index procedure? (2) Which patient-related and procedure-related parameters associate with implant revision and hip disarticulation? (3) What are the overall mortality, oncologic outcome, minor complications, and reoperations in this study population?

This was a retrospective, multicenter European Musculo-Skeletal Oncology Society (EMSOS) study reporting data from 14 international participating centers. The study included 143 patients who received a TFR between January 1, 1990, and March 31, 2024. The mean ± SD age at index operation was 44 ± 24 years, and 52% (74 of 143) of the participants were men. Most patients underwent TFR for oncologic indications (76% [108 of 143]; 12% [13 of 108] received extendable growth prostheses). Complications, revisions, amputations, as well as clinical and surgical data were documented. We investigated major complications and hip disarticulation in a competing risk framework with death as the competing event.

The cumulative incidence of implant revision at 2 and 5 years was 24% (95% confidence interval [CI] 16% to 31%) and 35% (95% CI 26% to 44%). The cumulative incidence of hip disarticulation at 2 and 5 years was 4% (95% CI 1% to 7%) and 10% (95% CI 4% to 16%). We found that advanced patient age was associated with an increased risk for major complications (subdistribution HR 1.01 [95% CI 0.98 to 1.02]; p = 0.17, cause-specific HR 1.01 [95% CI 1.00 to 1.03]; p = 0.023). Furthermore, advanced patient age (subdistribution HR 1.03 [95% CI 1.01 to 1.05]; p < 0.001, cause-specific HR 1.05 [95% CI 1.02 to 1.07]; p < 0.001) and no mesh graft (subdistribution HR 0.30 [95% CI 0.10 to 0.92]; p = 0.035, cause-specific HR 0.46 [95% CI 0.15 to 1.42]; p = 0.18) were associated with higher risk for hip disarticulations. No other risk factor was associated with altered risk for implant revision or hip disarticulation.

Patients should be informed about the high incidence of revision associated with TFR and the secondary hip disarticulation risk. The identified risk factors may be considered upon patient counseling, as well as for surgical decision-making. Our findings confirm the beneficial effects of mesh grafts. As technical solutions for patients undergoing amputations advance, the indications for these complex reconstructions should be chosen carefully, especially in older patients.

Level III, therapeutic study.