Nuclear Medicine Scans in Total Joint Replacement.

» A 3-phase bone scan is a potential first-line nuclear medicine study for pain after total joint arthroplasty (TJA) when there is concern for periprosthetic joint infection or aseptic loosening. » In patients who have a positive bone scintigraphy result and suspected infection of the joint, but where aspiration or other studies are inconclusive, labeled leukocyte scintigraphy with bone marrow imaging may be of benefit. » Magnetic resonance imaging (MRI), while not a nuclear medicine study, also shows promise and has the advantage of providing information about the soft tissues around a total joint replacement. » Radiotracer uptake patterns in scintigraphy are affected by the prosthesis (total knee arthroplasty [TKA] versus total hip arthroplasty [THA]) and the use of cement. » Nuclear medicine scans may be ordered 1 year postoperatively but may have positive findings that are due to normal physiologic bone remodeling. Nuclear studies may be falsely positive for up to 2 years after TJA. » Single-photon emission computed tomography (SPECT) combined with computed tomography (CT) (SPECT/CT), fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT, and MRI show promise; however, more studies are needed to better define their role in the diagnostic workup of pain after TJA.