Preliminary clinical results of coated porous tibia cones in septic and aseptic revision knee arthroplasty

Purpose

To analyze the first results of calcium-phosphate-coated porous tibia cones.

Methods

Patients treated with TrabecuLink^®-CaP Cones were retrospectively recruited from January 2016 to December 2017. These custom-made cones were produced using titanium alloy Ti–6Al–4 V (Tilastan^®) and using additive manufacturing with a special calcium-phosphate coating (HX^®-coating). Clinical outcome was evaluated using Oxford Knee Score. For radiological evaluation of the implants, patients sent us outpatient taken radiographs. A minimum follow-up of one year was required. Lastly, we analyzed postoperative complications and revision rates.

Results

52 patients with revision knee arthroplasty (RKA) were recruited for final analysis, of whom, we had 17 septic RKAs (33%) and 35 aseptic cases of RKA (67%). The bone defects were grouped into 17 AORI Type 2A (32.7%), 14 Type 2B (26.9%) and 21 Type 3 (40.4%). After a mean follow-up of 22 months (13.2–34.8; SD = ± 10), we had 4 surgical revisions (7.7%), 2 septic and 2 aseptic cases. The mean Oxford Knee Score was 28.6 points (8–47; SD = ± 10). 22 of 28 radiographs (78.6%) showed regular positioning of the cones and TKAs at a mean follow-up of 16.8 months (13.2–34.8; SD = ± 6). Three patients (10.7%) showed slight radiolucencies in the bone–cement interfaces and 3 patients (10.7%) had beginning heterotopic ossifications.

Conclusions

This study shows the initial clinical results of calcium-phosphate-coated tibia cones showing a good functional outcome. Further research should focus on long-term clinical and radiological follow-up.