Nononcologic Applications of PET/CT and PET/MRI in Musculoskeletal, Orthopedic, and Rheumatologic Imaging: General Considerations, Techniques, and Radiopharmaceuticals.

PET is often underutilized in the field of musculoskeletal imaging, with key reasons including the excellent performance of conventional musculoskeletal MRI, the limited spatial resolution of PET, and the lack of reimbursement for PET for nononcologic musculoskeletal indications. However, with improvements in PET/CT and PET/MRI over the last decade as well as an increased understanding of the pathophysiology of musculoskeletal diseases, there is an emerging potential for PET as a primary or complementary modality in the management of rheumatologic and orthopedic patients. Specific advantages of PET include the convenience of whole-body imaging in a single session, the relative resilience of the modality compared with CT and MRI in the imaging of metallic implants, the ability to evaluate deep joints not amenable to palpation, and the potential for improved specificity of diagnosis with novel radiopharmaceuticals. In this review, we discuss multiple radiopharmaceuticals and technical considerations for PET/CT and PET/MRI that can be used in imaging of nontumoral bone and soft-tissue disorders. Both PET/CT and PET/MRI hold significant promise in the field of musculoskeletal imaging, and with further radiopharmaceutical development and clinical research, these hybrid modalities can potentially transform the current management of patients with orthopedic and rheumatologic disease.