Treatment Success Rate After Surgical Management of Periprosthetic Joint Infections in Oncologic Proximal Tibia Reconstruction

BACKGROUND: While the incidence of periprosthetic joint infection (PJI) after oncologic proximal tibia reconstruction (PTR) is well documented, limited data exists on the clinical course and infection eradication rates after PJI onset. Our study evaluated treatment success and functional outcomes associated with different surgical strategies for PJI after oncologic PTR. METHODS: We retrospectively identified patients treated for PJI after oncologic PTR with a megaprosthesis or allograft-prosthetic composite between 1995 and 2023 at two tertiary care institutions. Surgical strategies included debridement, antibiotics, and implant retention (DAIR), DAIR with modular component exchange and stem retention (DAIR plus), and two-stage revision. Reinfection-free survival (RFS) and amputation-free survival were evaluated using Kaplan-Meier analysis. Functional outcomes and quality of life were assessed at last follow-up using the Musculoskeletal Tumor Society (MSTS) and EuroQol (EQ-index) questionnaires. RESULTS: Six-month RFS was 22% for DAIR, 66.7% for DAIR plus, and 83.3% for two-stage revision (p = 0.002). At 2 years, DAIR plus and two-stage showed higher RFS compared to DAIR (p < 0.001). Median MSTS was 63.4%, and EQ index 68.4, with no differences between groups. CONCLUSIONS: DAIR plus showed non-inferior outcomes compared to two-stage revision and may be a feasible alternative in cases with well-fixed stems. Functional outcomes remain poor. LEVEL OF EVIDENCE: Level III.