Makarov VasylCity State Medical Hospital ?16, Ukraine
Title: The short-term outcomes of total hip arthroplasty using custom 3d titanium porous printed implants for acetabular defects
Background: total hip replacement with acetabular bone loss is a remains a problematic and debatable topic far from its final solution.
Purpose: Improve results of total hip arthroplasty using 3D custom-made titanium porous printed implants for acetabular defects in patients with acetabular Paprosky ?? and III defects.
Methods: In a prospective analysis, we included 8 patients (all females) undergoing cup primary (6 patients) and revision (2 patients) using a custom 3D printed implant. The indication was protrusion arthritis with osteoporosis as well as defect of posterior and superior wall of acetabular Paprosky II and ??? defects. Using 3D CT, we created for the first step 3D mathematical model in Solidwork software program. Then we simulated of the pre-operative 3D custom cup estimated inclination, anteversion, and center of rotation. There was 3D printed pelvic and cup from plastic and 3D custom cup from titanium powder Ti-6Al?4V using the laser powder bed fusion machine (ISO 13485:2016). Titanium porous structure were hexagon 350-400 micron. Plastic models facilitated during surgery orientation and identification of position before implantation of 3D custom cup.
Results: Our short-term outcomes measures were the 3D-CT-measured difference between planned and achieved of the 3D porous cup position were correct with 100% restoration of center of rotation and inclination as well as anteroposterior direction in 6 cases, in 2 cases we had insignificant upward displacement of center of rotation – 8-10 mm, and increase in inclination angle by 6-8°. There was no revision during 1 year after surgery. Post-operative Harris hip scores ranged from 92 to 95 in the short-term study. Radiographic outcomes were reported that in all patients was achieved total ingrowth spongious bone in porous of 3D titanium printed custom cups.
Conclusion: Custom 3D titanium porous printed cups are a reliable surgery option for severe acetabular defects and allow the reconstruction of the center of rotation as well as inclination and anteroposterior position. The authors propose using pre-op 3D planning and 3D printed plastic models to adapt of implants during surgery that show promising results in complex hip primary and revision surgery.
Keywords: 3D CT; custom 3D porous printed cups, image analysis for component orientation, acetabular Paprosky II and III defects; custom-made implant; revision hip surgery; total hip arthroplasty.