Patellar fractures are associated with rheumatoid arthritis, steroid use, osteonecrosis, and malalignment. Most patients with periprosthetic fractures are elderly, having poor bone stock. Treatment depends Imaging After Total Knee Arthroplasty on fracture classification, which often includes information regarding fracture location, degree of comminution, and position and stability of the prosthesis. 3-Phase Bone Scan Knee Radionuclide 3-phase bone scans can demonstrate increased activity at a site of periprosthetic fracture and can show fractures that are radiographically occult [137,138]. In older osteopenic individuals with low rates of bone remodeling, it may take 48 to 72 hours for the development of increased radionuclide activity at the site of fracture. Within 1 to 2 years after prosthesis surgery, the differential diagnosis for increased periprosthetic activity would include postoperative change; however, with serial imaging, this postoperative activity should decrease over time, whereas activity increasing over time would be suggestive of a prosthetic complication, such as a periprosthetic fracture, aseptic loosening, or infection. Therefore, no conclusion should be drawn on an isolated bone scan unless it yields a normal study. CT Arthrography Knee There is no benefit to intraarticular contrast. CT Knee With IV Contrast IV contrast is not helpful for CT assessment of periprosthetic fracture. CT Knee Without and With IV Contrast IV contrast is not helpful for CT assessment of periprosthetic fracture. CT Knee Without IV Contrast Radiographically occult fractures may be detected on CT when metal artifact reduction techniques are used [20]. FDG-PET/CT Whole Body There is insufficient evidence to support the use of FDG-PET/CT for the assessment of periprosthetic fractures. Fluoride PET/CT Whole Body There is insufficient evidence to support the use of fluoride PET/CT for the assessment of periprosthetic fractures.
Imaging After Total Knee Arthroplasty. Patellar fractures are associated with rheumatoid arthritis, steroid use, osteonecrosis, and malalignment. Most patients with periprosthetic fractures are elderly, having poor bone stock. Treatment depends Imaging After Total Knee Arthroplasty on fracture classification, which often includes information regarding fracture location, degree of comminution, and position and stability of the prosthesis. 3-Phase Bone Scan Knee Radionuclide 3-phase bone scans can demonstrate increased activity at a site of periprosthetic fracture and can show fractures that are radiographically occult [137,138]. In older osteopenic individuals with low rates of bone remodeling, it may take 48 to 72 hours for the development of increased radionuclide activity at the site of fracture. Within 1 to 2 years after prosthesis surgery, the differential diagnosis for increased periprosthetic activity would include postoperative change; however, with serial imaging, this postoperative activity should decrease over time, whereas activity increasing over time would be suggestive of a prosthetic complication, such as a periprosthetic fracture, aseptic loosening, or infection. Therefore, no conclusion should be drawn on an isolated bone scan unless it yields a normal study. CT Arthrography Knee There is no benefit to intraarticular contrast. CT Knee With IV Contrast IV contrast is not helpful for CT assessment of periprosthetic fracture. CT Knee Without and With IV Contrast IV contrast is not helpful for CT assessment of periprosthetic fracture. CT Knee Without IV Contrast Radiographically occult fractures may be detected on CT when metal artifact reduction techniques are used [20]. FDG-PET/CT Whole Body There is insufficient evidence to support the use of FDG-PET/CT for the assessment of periprosthetic fractures. Fluoride PET/CT Whole Body There is insufficient evidence to support the use of fluoride PET/CT for the assessment of periprosthetic fractures.