The Use of Tantalum Metaphyseal Cones for the Management of Severe Bone Defects in Septic Knee Revision

Background: Femoral and tibial massive bone defects are common findings in septic total knee revision and pose considerable challenges for the orthopedic surgeon. The aim of this study was to report the midterm clinical and radiographic outcomes with the use of tantalum cones for the management of massive bone defects after 2-stage knee revision. Methods: We retrospectively reviewed the medical records of 60 patients (mean age, 67.9 ± 8.8 years) treated with 94 tantalum cones associated with constrained or semiconstrained knee for massive bone loss (mean follow-up, 43.5 ± 17.4 months). In all cases, the indication was a staged revision for periprosthetic knee infection. Functional scores, radiographic outcomes, and implant survivorship were analyzed. Results: The mean Knee Society Score and Oxford Knee Score improved from 44.1 ± 7.4 and 19.2 ± 4.1 to 85.4 ± 5.6 and 38.4 ± 3.9 (P <.01), respectively. The mean flexion increased from 60.6° ± 15.5° to 96.8° ± 10.9° at the last evaluation (P <.01). The mean improvement in flexion contracture was 6.2 ± 8.0 (P <.01). Two failures (3.3%) due to periprosthetic knee infection recurrence were observed, but no cone-related mechanical failures were reported. The cone-related survival rate was 97.8%. Conclusion: Excellent clinical and radiographic midterm outcomes were achieved with a low complication rate. Tantalum cones may be considered a safe and effective option in the management of massive bone defects also in septic knee revision surgery.