Wire-stem fretting and galvanic corrosion as an underrecognized cause of metallosis after hip arthroplasty: A rare case report.

Although metallosis after hip arthroplasty is most often attributed to bearing wear or trunnion corrosion, auxiliary fixation devices may also serve as a potential source. In this article, we report a rare case in which direct contact between a stainless-steel cerclage wire and a titanium femoral stem produced localized metallic debris and a peri-stem pseudotumor, consistent with fretting and galvanic corrosion. Ten years after index total hip arthroplasty complicated by an intraoperative femoral fracture treated with cerclage, the patient presented with groin pain and a cystic lesion with solid components adjacent to the femoral stem. Revision surgery revealed black-stained tissue concentrated at the wire-stem interface. Histological examination confirmed metallic debris with chronic inflammation. After extensive debridement and revision to a distally fixed stem, pain on the Visual Analog Scale (VAS) decreased from 5 to 1, and the Harris Hip Score (HHS) improved from 70 to 93 at six months. In conclusion, this case serves as a reminder that even auxiliary fixation devices, such as stainless-steel cerclage wires placed for intraoperative fracture stabilization, can generate metallic debris and lead to metallosis when they come into contact with titanium stems. Surgeons, therefore, should avoid direct contact between stainless-steel and titanium components, or otherwise interpose an insulating layer when cerclage fixation is required.