Radionuclide imaging: Past, present and future outlook in the diagnosis of infected prosthetic joints
Hell J Nucl Med
Objective: A serious complication of joint replacement surgery is infection, which results in prolonged invalidity as well as removal and subsequent re-implantation after lengthy antibiotic therapy. In terms of diagnostic imaging, nuclear medicine has presented several tracers and imaging modalities over the years to be used in prosthetic joint infection. The PubMed/MEDLINE literature database was systematically examined for publications on infection, arthroplasty, joint replacement, prosthetic joint, gallium, labeled leukocytes, sulfur colloid, antimicrobial peptides, Fluorine-18-fluorodeoxyglucose (F-18-FDG), positron emission tomography/computed tomography (PET-CT), and single-photon emission (SPET-CT). This was determined to be a comprehensive review, not a meta-analysis of prosthetic joint infection and diagnostic imaging in the field of nuclear medicine. Prosthetic joint replacement is more frequently being employed as a way of improving the quality of life in an ever-ageing population. Complications following joint replacement surgery include aseptic or mechanical loosening, as well as polyethylene wear and prosthetic joint infection. The rate of infection is estimated to be between 1%-3%. The therapeutic management of these complications lies in the ability to differentiate between infection and aseptic mechanical loosening. Given that plain radiographs are neither sensitive nor specific to infection and computer tomography, as well as magnetic resonance imaging are limited due to metal-induced artifacts, radionuclide imaging has come to aid in the diagnostic imaging in the failed joint replacement. However, each modality has its advantages and disadvantages, thus there is no gold standard technique of radionuclide imaging. Nevertheless, radiolabelled leukocyte scintigraphy has proven itself to be the gold standard in neutrophil-based infection processes. Several studies have examined the role of PET using radiotracers such as F-18-FDG, gallium-67 and F-18, as well as SPET-CT in diagnosing prosthetic joint infections. Other radiotracers, such as antigranulocyte antibodies and fragments, as well as radiolabeled antibodies and antimicrobial peptide have yet to confirm their role in diagnostic imaging of the failed joint replacement. Nuclear medicine plays a vital role in diagnosing prosthetic joint infections. WBC/bone marrow imaging is the best available diagnostic imaging test. Newer imaging modalities, such as SPET-CT may in the future, play a larger role in diagnosing prosthetic joint infections. The roles of F-18-PET and F-18-FDG-PET have yet to still be determined.
School of Medicine