Imaging Metal-on-Metal Hip Replacements: the Norwich Experience.

Background: Adverse reaction to metal debris is a relatively recently described and often a silent complication of metal-on-metal (MOM) total hip replacements (THR). The Norfolk & Norwich University Hospital has been performing metal artefact reduction (MARS) MRI for 8 years in a variety of different types of MOM THR.

Questions/purposes: The aims of this review are to describe the experience of using MARS MRI in Norwich and to compare our experience with that published by other groups.

MRI of aseptic lymphocytic vasculitis-associated lesions in metal-on-metal hip replacements.

Objective: The aim of this review is to describe the clinical, histopathologic, and MRI features of aseptic lymphocytic vasculitis-associated lesions in total hip replacements.

Conclusion: The introduction of modern metal-on-metal hip arthroplasty has been accompanied by a newly described disease, aseptic lymphocytic vasculitis-associated lesions, which is characterized histologically by bland necrosis and dense perivascular lymphocytic infiltrates. Conventional radiographic findings are often normal, but the typical MRI findings include periprosthetic fluid collections, soft-tissue masses, gluteal tendon avulsion, bone loss, periosteal stripping, neurovascular involvement, and periprosthetic fractures.

Grading the severity of soft tissue changes associated with metal-on-metal hip replacements: reliability of an MR grading system.

Introduction: Metal-on-metal (MoM) soft tissue reactions or aseptic lymphocytic vasculitis-associated lesions (ALVAL) are being recognised using metal artefact reduction (MAR) MR with increasing frequency following the advent of second generation metal-on-metal bearings, but there is no standardised technique for reporting of MR appearances in this disease. The aim of this study was to measure the reliability of a grading system designed for scoring the severity of MoM disease on MRI.

Materials And Methods: MRI examinations of 73 hips in 59 patients were retrospectively selected and then anonymised, randomised and reviewed by three independent observers (musculoskeletal radiologists).

Long-term clinical, radiological and histopathological follow-up of a well-fixed Mckee-Farrar metal-on-metal total hip arthroplasty.

Metal-on-metal is one potential bearing option for total hip arthroplasty (THA). Proponents of the bearing have suggested that if the tribology is optimal, volumetric wear may occur at levels at least one order of magnitude lower than metal-on-polyethylene bearings. We present a unique postmortem case of a well fixed, metal-on-metal, McKee-Farrar total hip arthroplasty implanted 30 years previously that was clinically asymptomatic in life.