Short-Term Survivorship of 3D-Printed Titanium Metaphyseal Cones in Revision Total Knee Arthroplasty: A Systematic Review.

Background: Several studies have evaluated the outcomes of tantalum cones in revision knee arthroplasty with moderate-to-severe metaphyseal bone defects. However, recent innovations have led to the development of 3-D printed titanium cones to better adapt to host bone, there remains no consensus on their overall performance.

Objective: We therefore performed a systematic review of the literature to examine short-term survivorship and complication rates of their usage in revision TKAs.

Methods: A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive search of PubMed, MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews was conducted for English articles using various combinations of keywords.

Results: In all, 7 articles met the inclusion criteria. A total of 687 cones were implanted in 557 revision TKAs. The all-cause revision-free survivorship of the implants was 95.3% (26 revisions), and of the cones was 95.5% (31 cones revised) at mean 24 months follow-up. The cones revision-free survivorship from aseptic loosening was 99.7%. The overall complication rate was 19.7% with infection as the most common complications observed and the most frequent reason for revision with an incidence of 10.4% and 4.1%, respectively. Overall, functional outcomes improved as documented by postoperative knee scores.

Conclusion: 3-D printed metal cones represent a reliable option in metaphyseal bone defects reconstruction that provides high fixation, good short-term survivorship, and complications rates in line with similar devices. In addition, they are associated with lower intraoperative complications, and higher survivorship from aseptic loosening.