• BACKGROUND
    • There is a paucity of data on the outcomes of distal femoral replacements (DFRs) in patients with total knee arthroplasty (TKA) periprosthetic fractures. We sought to characterize these patients' survivorship free from rerevision.
  • METHODS
    • We retrospectively identified 49 patients, including 34 after primary TKA (primary cohort), 9 after revision TKA, and 6 conversions for failed open reduction and internal fixation (revision cohort) that underwent DFR for a periprosthetic femur fracture. The mean age was 76 years, and 40 patients (82%) were female. The mean follow-up was 4 years. Femoral fixation included 44 cemented stems (90%) and 5 cementless stems (10%). Survivorship free from rerevision was characterized by the Kaplan-Meier method; cox proportional regression was used to analyze the risk factors for rerevision.
  • RESULTS
    • Survivorship free from any rerevision at 5 years in the primary and revision cohort was 93% and 18%, respectively. The revision cohort had a 5.3× higher risk of re-revision (P = .008). Survivorship free from re-revision for aseptic loosening at 5 years in the primary and revision cohort was 93% and 53%, respectively. Two of the 3 patients with cementless stems in the primary cohort underwent early rerevision for aseptic loosening, but patients with prior primary TKAs treated with cemented femoral fixation (n = 31) had a 97% 5-year survivorship free from re-revision.
  • CONCLUSION
    • Patients with periprosthetic fractures around prior primary TKAs treated with DFRs with cemented femoral fixation had a 97% 5-year survivorship free from any re-revision. DFRs for periprosthetic femur fractures around revision TKAs or conversions of failed open reduction and internal fixations have a 5× increased risk of rerevision.