Revision total knee arthroplasty: Experience with tantalum cones in severe bone loss

摘要

Background: Tantalum-made cones have been developed to compensate for large bone defect involving metaphyseal segment or major portion of the condyle or plateau during knee revision prosthetic surgery. Materials and methods: We present our experience with femoral and tibial tantalum cones in 11 knees (12 cones overall were used, 6 on femur and 6 on tibia) with 2B or 3 Engh defect type during knee revision arthroplasty. Both cemented and cementless cones were used. Patients were submitted to a specific study protocol in order to exclude a new or persistent infection. Only one intra-operative complication not related to the implantation of the trabecular metal cone was observed. Results: Neither early nor late post-operative re-infection was reported in our series at a mean follow-up of 39.8 months. Radiological analysis showed no cases of aseptic loosening or migration of the components. The only post-operative complication was delayed union of the tibial tuberosity in a patient who required osteotomy for surgical exposure. All patients improved both clinically and functionally. Conclusions: The results of this study support the use of femoral and tibial porous tantalum metaphyseal cones as a viable option for revision knee arthroplasty with large amount of bone defects in both tibia and femur. We think that the main advantages of tantalum cones compared to structural bone graft lie in faster full weight-bearing recovery and in the cones' potential long-term maintenance of mechanical support. By our results, we can eventually exclude any concern regarding a possible direct correlation of the trabecular metal cones with re-infection.