PET and SPECT in Osteomyelitis and Prosthetic Bone and Joint Infections: A Systematic Review

Objective To review the literature on diagnostic accuracy and clinical value of single-photon emission computed tomography (SPECT) and positron emission tomography (PET) for imaging of bone and joint infections. Methods The PubMed/MEDLINE and Embase (OvidSP) literature databases were systematically searched for publications on SPECT and PET on osteomyelitis and prosthetic bone and joint infections using specific guidelines with MeSH-terms, truncations, and completion using cross-references. Results In 44 original articles (15 for SPECT and 29 for18 F-fluorodeoxyglucose [FDG]-PET) on osteomyelitis and prosthetic bone and joint infection, 1634 patients were included (580 patients SPECT, 1054 patients FDG-PET). Level of evidence (Oxford criteria) was 2-3b . For SPECT, the highest diagnostic accuracy of 95% for diagnosis of bone and joint infections is achieved with combined111 In-WBC and99m Tc-sulfur colloid. Acceptable diagnostic accuracy was also obtained with99m Tc-WBC or111 In-WBC combined with99m Tc-methylene diphosphonate (99m Tc-MDP). FDG-PET is useful for diagnosis of osteomyelitis with a sensitivity and specificity generally over 95%. In patients with orthopedic implant infections, sensitivity varies widely from 28% to 91% and specificity from 9% to 97%. This variation in FDG-PET performance in orthopedic implant infections depends largely on the (use of different) criteria to diagnose infection. Determination of the best criteria is still a matter of debate. Conclusions SPECT/computed tomography (CT) with111 In-WBC combined with99m Tc-MDP or99m Tc-sulfur colloid seems to be the best imaging technique for diagnosis of bone and joint infections. FDG-PET is also useful for diagnosis of osteomyelitis with improved spatial resolution over SPECT imaging, allowing more accurate localization. Localization can be further improved by adding CT. Diagnosis of orthopedic implant infections with FDG-PET depends strongly on the localization of the implant and the criteria used to diagnose infection. Confirmation of well defined criteria to diagnose infection on FDG-PET in patients with metallic implants is thus of paramount importance for optimal diagnosis.