Weight-Bearing cone-beam CT in lower-limb osteoarthritis: Quantitative Assessment, clinical Applications, and Future Directions.

Osteoarthritis (OA) is a leading cause of joint pain and functional limitations in the elderly. Conventional imaging methods, including weight-bearing radiography (WB-XR), non-weight-bearing CT, and MRI, provide valuable structural information but cannot fully characterize three-dimensional joint morphology and biomechanical changes under physiological loading conditions. Weight-bearing cone-beam computed tomography (WBCT) has emerged as a functional imaging modality that integrates three-dimensional imaging with weight-bearing acquisition, enabling comprehensive evaluation of lower-limb alignment, rotational relationships, joint congruity, and joint space distribution. By combining the advantages of WB-XR and three-dimensional CT assessment in a single examination, WBCT provides a potential single-stop imaging workflow with improved efficiency and reduced need for multiple imaging procedures. Recent advances in quantitative analysis, including three-dimensional biometrics, distance and coverage mapping, and bone density assessment, have further expanded its applications in hip, knee, and foot/ankle osteoarthritis, as well as perioperative evaluation of alignment-correcting procedures and joint arthroplasty. Although WBCT demonstrates substantial value for osseous and biomechanical assessment, further studies are required to optimize acquisition protocols, validate quantitative biomarkers, and establish its role in longitudinal disease monitoring and personalized management of osteoarthritis.