[18F]-FDG-PET for the assessment of major infectious disorders of the musculoskeletal system.

Infections of the musculoskeletal system contribute substantially to global morbidity and healthcare expenditure, and conventional imaging frequently falls short of providing the sensitivity and specificity required for early diagnosis in complicated presentations. In this review, we examine the clinical role of [18F]-fluorodeoxyglucose positron emission tomography paired with computed tomography (FDG-PET/CT) or magnetic resonance imaging (FDG-PET/MRI) in the workup of these infections. Drawing on the published literature, we summarize evidence across osteomyelitis, spondylodiscitis, septic arthritis, and prosthetic joint infection, with attention to reported diagnostic performance and to where each hybrid technique appears to be most useful. Across infection types, FDG-PET/CT consistently shows good diagnostic accuracy, is widely available, and tolerates metallic hardware well, whereas FDG-PET/MRI, though still investigational and confined to a small number of academic centers, offers improved soft-tissue contrast and lower cumulative radiation, which may be advantageous in selected cases such as spondylodiscitis or in patients requiring serial imaging. The available comparative evidence remains limited, much of it drawn from small, single-center cohorts. We therefore emphasize that current data should be viewed as preliminary. Modality choice in practice depends on the clinical question, patient factors, local availability, and cost, rather than on a one-size-fits-all preference.