Background and purpose: Revision procedures and the resulting bone loss are still a big challenge for orthopedic surgeons. Therefor we checked, what post-operative functional outcomes 3D printed Cone augments offer in patients with bone defects (AORI classification type 2 and 3) of the knee joint and does use of Cones can delay the necessity to use resection prothesis?Methods Data from 64 patients (M=22; W=42) who underwent a total knee arthroplasty (TKA) revision in two clinical hospitals were included in the retrospective analysis. 3D printed Cones were used in all patients. The Knee Society Clinical Rating System (KSS) and the range of motion in the knee joint were used for the functional assessment of patients.Results The mean follow-up was 22 months (range, 12 to 38 months). Survival for aseptic loosening at follow-up was 100%. Infection occurred in 2 (3.1%) patients. The mean KSS score increased from 12.75 points preoperatively to 66.56 points postoperatively (p <0.001). While the mean range of motion in the knee joint changed from 61.15 degrees preoperatively to 115.93 degrees postoperative (p <0.001).Conclusion Due to the good functional results of patients and the low rate of complications, 3D printed Cone augments seems to be a good solution for patients requiring a TKA revision procedure. When used in patients with bone defects classified as 2B and 3 (AORI), they can be a good alternative, delaying the need for resection prostheses.