Total knee arthroplasty revision with trabecular tantalum cones: Preliminary retrospective study of 51 patients from two centres with a minimal 2-year follow-up

BackgroundSuccessful management of large bone defects is of crucial importance when performing revision total knee arthroplasty (TKA). Trabecular tantalum cones may improve prosthesis fixation via their potential for reconstructing a stable metaphyseal support. The objective of this study was to evaluate the clinical and radiological outcomes and the complications of tantalum cones in revision TKA.HypothesisTrabecular tantalum cones provide stable and durable metaphyseal reconstruction when used during revision TKA.Material and methodsTrabecular Metal™ cones (Zimmer, Warsaw, IN, USA) were used for 52 revision TKAs in 51 patients (mean age, 68 ± 9 years) managed in two centres between 2008 and 2013. A rotating hinge prosthesis was chosen for 38 (73%) knees and a condylar constrained knee prosthesis for 14 (27%) knees, with 37 tibial and 34 femoral cones. The two most common reasons for revision surgery were aseptic loosening (n = 22, 42%) and infection (n = 19, 37%). The bone loss was severe in most cases. At each centre, after a mean follow-up of 34 months (range, 24–52 months), two independent observers assessed the Knee Society Score (KSS), range of motion, mechanical axis, and osteo-integration for each patient.ResultsMean KSS increased from 46 preoperatively to 77 (P = 0.001) at last follow-up and the mean KSS function from 39 to 57 (P = 0.007). Mean range of motion improved from 93° (45°–120°) to 110° (65°–130°) (P = 0.001). Mean postoperative mechanical axis was 180° (172°–190°). Radiographic evaluation showed evidence of osteo-integration for all cones. Four revisions were performed for recurrence of infection but none for mechanical failure.DiscussionThe findings of our study confirm the biomechanical and biological reliability of Trabecular Metal™ cones used to fill metaphyseal bone defects during revision TKA.Level of evidenceIV, retrospective therapeutic study.