Opportunistic Metabolic and Sarcopenia Assessment on Routine Spinal Imaging: A Scoping Review of State of the Art and Future Perspectives

Interest is growing about the opportunistic use of imaging data. We conducted a scoping review to provide an overview and define perspectives and gaps in knowledge for the opportunistic extraction of measurements of skeletal muscle and fat quantity or quality from spinal examinations. A comprehensive search on PubMed was performed with key terms such as "sarcopenia," "obesity," "fat," and "muscle," focusing on spine computed tomography and magnetic resonance imaging. Only articles published in the previous 5 years were included. We identified 29 studies, most of which were classified as level of evidence 3/4 and had significant limitations. The clinical settings were diverse, including spine surgery, osteoporosis, degenerative spine disease, and low back pain. This work highlights that an opportunistic assessment of paravertebral muscles by computed tomography/magnetic resonance imaging is feasible, although more evidence is needed to clarify the relationship between specific pathologic conditions and muscle loss/degeneration (aside from aging and disuse) before clinical implementation.