Excellent mid-term follow-up for a new 3D-printed cementless total knee arthroplasty

Abstract

Aims Cementless total knee arthroplasty (TKA) offers the potential for strong biological fixation compared with cemented TKA where fixation is achieved by the mechanical integration of the cement. Few mid-term results are available for newer cementless TKA designs, which have used additive manufacturing (3D printing). The aim of this study was to present mid-term clinical outcomes and implant survivorship of the cementless Stryker Triathlon Tritanium TKA. Methods This was a single institution registry review of prospectively gathered data from 341 cementless Triathlon Tritanium TKAs at four to 6.8 years follow-up. Outcomes were determined by comparing pre- and postoperative Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) scores, and pre- and postoperative 12-item Veterans RAND/Short Form Health Survey (VR/SF-12) scores. Aseptic loosening and revision for any reason were the endpoints which were used to determine survivorship at five years. Results At mid-term follow-up, the mean KOOS JR score improved significantly from 33.14 (0 t0 85, standard deviation (SD) 21.88) preoperatively to 84.12 (15.94 to 100, SD 20.51) postoperatively (p < 0.001), the mean VR/SF-12 scores improved significantly from physical health (PH), 31.21 (SD 5.32; 23.99 to 56.77) preoperatively to 42.62 (SD 10.72; 19.38 to 56.82) postoperatively (p < 0.001) and the mental health (MH), 38.15 (SD 8.17; 19.06 to 60.75) preoperatively to 55.09 (SD 9.64; 19.06 to 66.98) postoperatively (p < 0.001). A total of 11 revisions were undertaken, with an overall revision rate of 2.94%, including five for periprosthetic joint infection (1.34%), three for loosening (0.80%), two for instability (0.53%), and one for pain (0.27%). The overall survivorship was 97.06% and survivorship for aseptic loosening as the endpoint was 98.40%, with a 99.5% survivorship of the 3D-printed tibial component. Conclusion This 3D-printed cementless total knee system shows excellent survivorship at mid-term follow-up. This design and the ability to obtain cementless fixation offers promise for excellent long-term durability. Cite this article: Bone Joint J 2021;103-B(6 Supple A):32–37.

No component loosening of a cementless deep dish rotating platform knee at a 5-year follow-up

“…Additionally, all evaluated clinical and patient reported outcome scores including AKSS, OKS, KOOS and EQ5D showed significant improvements within the FU when compared to the preoperatively assessed values. Similar results were retrieved by other authors, who also reported a significant improvement of PROMS after cementless TKA [ 26 ].…”

Early Tibial Component Fractures in a Cementless, 3D-Printed, Titanium Implant

“…The tibial pegs served as an extension of the limited bone fixation, which became an additional stressor from the lack of even bone ongrowth. Another possible mechanism leading to component fatigue failure can be instability/subluxation, which has been documented in several studies during short- to mid-term follow-up [ 5 , 6 , 8 ].…”

“…Long-term survivorship and outcome studies specific to a cementless highly porous titanium tibial baseplate are limited with the largest follow-up study currently reporting 5-year follow-up data on 228 patients [ 5 , 7 ]. No implant fractures of this design have been reported in these short-term to mid-term follow-up studies [ 5 , 7 , 8 ].…”

WiForceSticker: Batteryless, Thin Sticker-like Flexible Force Sensor

“…Due to the thin form factor and batteryless feature, these force stickers would be apt candidates to enable smart force-sensitive implants. Today, the field of medical orthopedic implants is already looking to engineering fields for innovation, with personalized 3-D printed implants making a lot of headway [13][14][15]. The implants can be made much smarter by adding these force stickers on top of these 3-d printed structures; since these are highly flexible, the sticker would conform well to the implant's irregular personalized shape and be able to measure the bone joint forces as shown in Figure 2(b).…”