Magnetic Resonance Imaging Evaluation of the Painful Total Knee Arthroplasty

Abstract

Optimization of metal artifact reduction pulse sequences over the past decade has rendered MRI valuable in knee arthroplasty assessment. MRI can reliably predict the presence and extent of infection, component loosening and polyethylene wear, and component malrotation, and it can evaluate the integrity of surrounding soft tissue structures. Using dynamic contrast-enhanced angiographic techniques, vascular pathology such as pseudoaneurysm formation and recurrent hemarthrosis can also be assessed.

Magnetic Resonance Imaging Around Metal at 1.5 Tesla

“…Although the diagnosis of periprosthetic joint infection ultimately relies on aspiration of joint fluid and subsequent microbiological analysis, imaging can be predictive. However, unless osseous destruction or periostitis is present, infection in early stages are often not detected on radiographs 138 . Using a basic MARS protocol (FSE sequences with optimized receive bandwidth), a “lamellated” or multiple-layered appearance of the synovium has been shown to hint at periprosthetic infection with a sensitivity of 0.86 to 0.92 and specificity of 0.85 to 0.87 139 .…”

“…Using a basic MARS protocol (FSE sequences with optimized receive bandwidth), a “lamellated” or multiple-layered appearance of the synovium has been shown to hint at periprosthetic infection with a sensitivity of 0.86 to 0.92 and specificity of 0.85 to 0.87 139 . In patients with unexplained anterior knee pain after arthroplasty, rotational malalignment of the components can be causative 138 . Traditionally, CT has been used to evaluate rotational alignment after total knee replacement; however, basic MARS-MRI has been shown to be an effective modality in evaluating component rotational alignment in unicondylar and total knee replacement 140,141 .…”

“…However, unless osseous destruction or periostitis is present, infection in early stages are often not detected on radiographs. 138 Using a basic MARS protocol (FSE sequences with optimized receive bandwidth), a "lamellated" or multiple-layered appearance of the synovium has been shown to hint at periprosthetic infection with a sensitivity of 0.86 to 0.92 and specificity of 0.85 to 0.87. 139 In patients with unexplained anterior knee pain after arthroplasty, rotational malalignment of the components can be causative.…”

“…139 In patients with unexplained anterior knee pain after arthroplasty, rotational malalignment of the components can be causative. 138 Traditionally, CT has been used to evaluate rotational alignment after total knee replacement; however, basic MARS-MRI has been shown to be an effective modality in evaluating component rotational alignment in unicondylar and total knee replacement. 140,141 Identical to findings in the hip, typical MARS-MRI findings of polyethylene wear-induced tissue reactions comprise a thickened synovial lining with dense synovial proliferation and debris, typically with low-to-intermediate signal intensity, variable amounts of joint fluid, and capsule distention and geographic osteolysis containing particulate debris of intermediate signal intensity.…”

Management of Bone Loss in Revision Total Knee Arthroplasty: An International Consensus Symposium

“…MRI imaging is superior for assessing soft-tissue complications and it is valuable for evaluating the component-bone interface for osteolysis with metal artifact reduction sequences [167]. MRI can detect osteolysis that is not visible on radiographs [33] and can show synovial changes due to particle disease before osteolytic lesions become apparent [190]. Interpretation might be difficult, and a special, technically trained radiology team for recording the sequences might be helpful, although MRI sequences have improved [147].…”