Magnetic resonance imaging in post-operative hip: Navigating the “Forbidden” landscape

The rising incidence of hip arthroplasty procedures, combined with demographic trends and concerns over metal-on-metal implant complications, has created an urgent need for accurate diagnostic methods for patients with hip replacements. While conventional radiography remains the initial investigation of choice, it often fails to detect or accurately assess the full extent of complications. Magnetic resonance imaging (MRI) has emerged as a vital diagnostic tool in post-arthroplasty evaluation, particularly through advances in conventional pulse sequences and metal artifact reduction techniques that enable better visualization of bone structures, implant-tissue interfaces, and surrounding soft tissues. This imaging modality effectively identifies various post-arthroplasty complications, including stress reactions and fractures, aseptic loosening and bone resorption, inflammatory responses to polyethylene wear, adverse local tissue reactions to metal debris, infections, and neuromuscular complications, which will be reviewed in this article. The enhanced capabilities of MRI with these optimized techniques provide crucial information that guides diagnosis, prognostic assessment, risk evaluation, and surgical planning, making it an indispensable tool in the post-arthroplasty care pathway.