Comparative Outcomes of Distal Femoral Replacement Versus Operative Fixation for Periprosthetic Distal Femur...

Periprosthetic distal femur fractures (PDFFs) are challenging injuries that commonly affect elderly patients following total knee arthroplasty (TKA). The commonly used surgical interventions are distal femoral replacement (DFR) and open reduction and internal fixation (ORIF), although the best approach remains debatable. This study aimed to evaluate the different ORIF subtypes and compare DFR versus ORIF for the management of PDFFs. This study was conducted in strict accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was registered with International Prospective Register of Systematic Reviews (PROSPERO). A comprehensive search was conducted across various databases up to October 2025. This study included only cohort studies comparing various surgical management approaches. Primary outcomes included functional scores (Knee Society Score (KSS)/Knee Society Function Score (KSFS)/Oxford Knee Score (OKS)), reoperation, and range of motion (ROM). Risk of bias and methodological quality were assessed using the Methodological Index for Non-Randomized Studies (MINORS) tool. Fifteen retrospective comparative studies involving 1,417 patients were included. Pooled analysis demonstrated a statistically significant reduction in reoperation rates favoring DFR (OR = 0.64; 95% CI: 0.42-0.97). One-year mortality showed a non-significant trend favoring DFR (OR = 0.70; 95% CI: 0.45-1.09). Infection rates were slightly higher in the DFR group without statistical significance (OR = 1.39; 95% CI: 0.61-3.18). No significant differences were observed in perioperative and functional outcomes between the two interventions. DFR allowed earlier full weight-bearing and mobilization, whereas ORIF required protected weight-bearing protocols. Compared with ORIF in PDFFs, DFR was associated with a reduced risk of reoperation and earlier postoperative mobilization. Mortality and functional outcomes remained comparable between the two interventions. Treatment selection should be individualized, with ORIF appropriate for reconstructible fractures with stable implants and DFR reserved for patients in whom fixation is unlikely to succeed or protected weight-bearing is unrealistic; all findings should be interpreted cautiously given the retrospective evidence base.