Role of Nuclear Medicine in Diagnosis of the Infected Joint Replacement

Abstract

Some complications of joint replacement surgery are easily diagnosed; however, differentiating infection from aseptic loosening is difficult because these entities are remarkably similar at clinical and histopathologic examination. Clinical signs and symptoms, laboratory tests, radiography, and joint aspiration are insensitive, nonspecific, or both. Cross-sectional imaging modalities are hampered by artifacts produced by the prosthetic devices themselves. Radionuclide imaging is not affected by the presence of metallic hardware and is therefore useful for evaluating the painful prosthesis. Bone scintigraphy is useful as a screening test, despite an accuracy of only 50%-70%, because normal results essentially exclude a prosthetic complication. The addition of gallium-67, a nonspecific inflammation-imaging agent, improves the accuracy of bone scintigraphy to 70%-80%. The accuracy of combined leukocyte-marrow imaging, 90%, is the highest among available radionuclide studies. Its success is due to the fact that leukocyte imaging is most sensitive for detection of neutrophil-mediated inflammation (ie, infection). The success of leukocyte-marrow imaging is tempered by the limitations of in vitro labeling. In vivo labeling has been investigated, and a murine monoclonal antigranulocyte antibody appears promising. Some investigations have focused on fluorodeoxyglucose imaging. Although this method is sensitive, specificity is a concern.

FDG-PET for diagnosing prosthetic joint infection: systematic review and metaanalysis

“…Differentiating prosthetic joint infection from aseptic loosening is of crucial importance for appropriate patient management; the treatment of an infected joint prosthesis generally involves both systemic antibiotics for an extended period and exchange arthroplasty in one or two stages, whereas aseptic loosening usually requires a single revision arthroplasty [1,2]. Diagnosing prosthetic joint infection is difficult; clinical signs and symptoms, laboratory tests, radiography, and joint aspiration are insensitive, nonspecific, or both [5]. In addition, cross-sectional imaging modalities such as CT and MRI are hampered by artifacts produced by the prosthetic devices themselves [5].…”

“…Diagnosing prosthetic joint infection is difficult; clinical signs and symptoms, laboratory tests, radiography, and joint aspiration are insensitive, nonspecific, or both [5]. In addition, cross-sectional imaging modalities such as CT and MRI are hampered by artifacts produced by the prosthetic devices themselves [5]. Radiomay be more useful [5].…”

Patient and Personnel Radiation Exposure in Sentinel Lymph Node Practice

“…Erken görüntülerde aktivite tutulumunun normal olması enfeksiyonu dışlasa da özgüllüğü düşükdür. Protez implantasyonu sonrası kemiğin yeniden yapılanması veya septik ya da aseptik protez gevşemesi gibi patolojilerde kemik yapımı ve kanlanma arttığı için, protez çevresi dokularda difosfonatlar yoğun akümüle olurlar (26). Kemik sintigrafisi, ortopedik protez enfeksiyonu tanısında, yüksek hassasiyet ve düşük özgüllüğe sahiptir.…”

“…Kemik sintigrafisini yorumlamada, radyofarmasötik tutulum özelliklerindeki değişkenlikler nedeni ile asemptomatik hastalarda ve özellikle diz protezlerinde sorunlar mevcuttur. Buna yönelik bazı araştırmacılar tarafından kantitatif analiz ve yorumlamada yardımcı olabilecek sınıflandırmalar denenmiş, ancak bu sorun çözülememiştir (9,10,25,26). Cerrahi sonrasındaki yıllarda aktivite tutulumları değişik oranlarda devam edebilir.…”

“…Bu nedenle, lökosit sintigrafisinde aktivite tutulumu mevcut iken kemik iliği görüntüsünde buna uyumlu aktivitenin olmaması enfeksiyonu gösterir. İki radyofarmasötiğin dağılımı benzer ise işaretli lökosit aktivitesi kemik iliğinde normal tutulumuna bağlıdır (26).…”