Pseudotumor and Subsequent Implant Loosening as a Complication of Revision Total Hip Arthroplasty with Ceramic-on-Metal Bearing: A Case Report

Abstract

Pseudotumors are not a single entity, but rather a spectrum of abnormal periprosthetic soft tissue reactions causing a granulomatous mass or destructive cystic lesion 1). These complications may developed in following surgeries involving metal-on-polyethylene (MoP) total hip arthroplasty (THA) due to polyethylene debris 2) and metal-on metal (MoM) THA due to metal debris 3,4). These lesions are non-neoplastic and believed to worsen progressively, resulting in extensive bone and soft tissue destruction 1). Pseudotumors are increasingly associated with THA; recent studies report incidences ranging from 0.27% 5) to 5% 6). To overcome the adverse effect of metal ion release in MoM arthroplasties, other hard bearings with improved quality were introduced (e.g., ceramic-on-ceramic [CoC] and ceramic-on-metal [CoM]) couples which are associated with minimal bearing surface wear. Importantly, there are limited clinical data relating to the use of CoM, with short duration of follow-up and Pseudotumors are not uncommon complications after total hip arthroplasty (THA) and may occur due to differences in bearing surfaces of the head and the liner ranging from soft to hard articulation. The most common causes of pseudotumors are foreign-body reaction, hypersensitivity and wear debris. The spectrum of pseudotumor presentation following THA varies greatly-from completely asymptomatic to clear implant failure. We report a case of pseudo-tumor formation with acetabular cup aseptic loosening after revision ceramic-on-metal hip arthroplasty. The patient described herein underwent pseudotumor excision and re-revision complex arthroplasty using a trabecular metal shell and buttress with ceramic-on-polyethylene THA. Surgeons should be aware of the possibility of a pseudotumor when dealing with revisions to help prevent rapid progression of cup loosening and implant failure, and should intervene early to avoid complex arthroplasty procedures.