Revision total knee arthroplasty using a novel 3D printed titanium augment: A biomechanical cadaveric study

Area of Science:

• Orthopedic Surgery
• Biomaterials Engineering
• Biomechanics

Background:

• Proximal tibial bone loss is a common challenge in revision total knee arthroplasty (rTKA), potentially compromising bone-implant fixation.
• A novel 3D printed titanium revision augment has been developed to address irregular proximal tibial anatomy.
• Evaluating the fixation stability of this augment in rTKA is crucial for improving surgical outcomes.

Purpose of the Study:

• To compare the fixation stability of rTKA utilizing a 3D printed titanium augment versus conventional cemented rTKA.
• To assess the early mechanical performance of the novel revision augment under eccentric loading.

Main Methods:

• Cadaveric tibias underwent primary total knee arthroplasty (pTKA), followed by revision surgery with either the 3D printed augment or a standard cemented stem.
• Fixation stability was evaluated using a three-stage eccentric loading protocol.
• Bone-implant micromotion was precisely measured using a high-resolution optical system.

Main Results:

• Revision TKA with the 3D printed augment demonstrated significantly less mean vertical micromotion (17.5 μm) compared to the conventional cemented group (28.1 μm).
• The experimental group exhibited statistically significant improvement in fixation stability (p = 0.029).

Conclusions:

• The novel 3D printed titanium augment provides superior early fixation stability in rTKA compared to traditional cemented techniques.
• The augment's press-fit fixation is likely adequate for promoting subsequent bone ingrowth.
• Further in-vivo studies are warranted to confirm long-term fixation efficacy.