Diagnostic Imaging - (Consensus)

There was one low strength investigation (Kraemer 1993) of hip arthroplasties in which combined bone gallium-67 imaging was performed. Sensitivity and specificity were 38% and 100%, respectively. A search of PubMed identified only 2 subsequent papers on gallium-67 imaging in periprosthetic joint infection. Yapar et al. (Eur J Nucl Med. 2001 Jul;28(7):822-30) studied 22 hip arthroplasties, 6 of which were infected and reported that gallium-67 imaging was 78% sensitive and 100% specific. Piriou et al. (Rev Chir Orthop Reparatrice Appar Mot. 2003 Jun;89(4):287-96) reported on the role of gallium-67 imaging for monitoring treatment response, not for diagnosing periprosthetic joint infection.

POSSIBLE HARMS OF IMPLEMENTATION
There may be a radiation dose associated with imaging of the site but it is small enough to pose no real risk to the patient. Some metal implants are not MRI safe which must be determined prior to imaging. Caution should be used with intravenous administration of iodinated and gadolinium based contrast agents to patients with impaired renal function (https://www.acr.org/Clinical-Resources/Contrast-Manual). Additionally, not all test options are available at each center which may have resource, access to care, and cost implications not fully delineated in these recommendations.

FUTURE RESEARCH
More high-quality evidence is needed to determine if ultrasound and MRI are useful in diagnosis of PJI, and higher quality diagnostic evidence is needed in order to create stronger recommendations.