Serum Titanium Following Total Ankle Arthroplasty

BACKGROUND: Little is known regarding the circulating metal levels in patients following total ankle arthroplasty (TAA). Also unknown is the impact of implant modularity. The purpose of this study is to quantify the postoperative serum metal levels in patients who have undergone primary TAA and to evaluate the impact of tibial component design. METHODS: A cross-sectional study was conducted of patients who had undergone primary TAA during 2010-2023. Ten patients with the Stryker INFINITY System were included in the nonmodular tibia group, 10 patients with the Stryker INBONE System were included in the modular tibia group, and 21 patients without implants were included as a control group. Subjects attended a 1-time visit at minimum 12 months postoperative. Outcome measures included serum cobalt, chromium, and titanium levels measured by inductively coupled plasma mass spectrometry. RESULTS: > .05). No associations were found between metal levels and clinical or radiographic outcomes. CONCLUSION: Results from this study provide the first evidence that TAA is associated with elevated serum metal levels. Serum titanium levels were elevated, whereas chromium and cobalt levels were not. Patients with modular tibial implants had higher titanium levels than patients with nonmodular tibial implants. Possible explanations for these findings may be related to the greater surface area of the modular implants or greater release of metallic debris from tribocorrosion at the numerous modular junctions. These findings regarding implant modularity are hypothesis-generating and require further study.