MR Imaging of Adverse Local Tissue Reactions around Rejuvenate Modular Dual-Taper Stems

Purpose: To describe the magnetic resonance (MR) imaging characteristics associated with adverse local tissue reactions and tissue damage around hip arthroplasties in which the recalled Rejuvenate modular dual-taper stem was used. Materials and Methods: The institutional review board of the Hospital for Special Surgery approved the study. All study patients provided informed consent. MR imaging studies were retrospectively reviewed in a cohort of 58 patients with 66 hip arthroplasties with Rejuvenate stems who had presented for imaging evaluation because of recall of the implant. Multiple regression analysis was used to examine MR imaging features, biomechanical factors, and metal ion levels as predictors of aseptic lymphocytic vasculitis-associated lesion (ALVAL) score at histologic assessment while adjusting for age and sex for 54 revised hips. Results: Revision surgery was performed in 54 hips on the basis of clinical or imaging findings (24% of hips were completely asymptomatic). The median ALVAL score among the revised hips was 9 (range, 1-10). Imaging characteristics observed with high frequency in patients with ALVAL included synovitis, mixed-or solid-type synovitis, synovial thickening, and capsular dehiscence. Conclusion: MR imaging provides an effective noninvasive method for assessing the presence and severity of adverse local tissue reaction, as well as the degree of pre-existing tissue damage, thereby facilitating early and accurate identification of candidates for revision surgery. (C) RSNA, 2015