Osteoarthritis year in review 2025: Imaging.

Area of Science:

• Orthopedics and Musculoskeletal Imaging
• Biomedical Engineering
• Radiology

Background:

• Osteoarthritis (OA) is increasingly recognized as a complex disease affecting multiple joint structures.
• Inflammation is a key feature across various tissues involved in OA pathogenesis.
• Traditional imaging methods are evolving with new technologies for better OA assessment.

Purpose of the Study:

• To review recent advancements in imaging for osteoarthritis (OA).
• To explore how emerging methods and multi-tissue assessments aid in disease characterization, early detection, and intervention.
• To synthesize findings from studies focusing on effusion-synovitis, infrapatellar fat pad, muscle, subchondral bone, and subcutaneous fat.

Main Methods:

• A narrative review of imaging studies on osteoarthritis published between March 2024 and March 2025.
• Comprehensive literature search of PubMed, Embase, and CINAHL.
• Selection and synthesis of 26 representative studies organized by affected joint tissues.

Main Results:

• OA involves multiple joint structures with inflammation as a common factor.
• Muscle quality and local adiposity are identified as key imaging biomarkers.
• Ultrasound and AI-enhanced radiography show promise for scalable clinical use in OA.
• Imaging findings correlate with biomechanical factors like gait and loading patterns.

Conclusions:

• Imaging research in OA is expanding, integrating multi-tissue assessments.
• Advances in imaging methods enable earlier OA detection and more precise symptom assessment.
• New imaging insights support the development of targeted, structure-informed OA interventions.