Wide association study of radiological features that predict future knee OA pain: Data from the OAI

Knee pain is a common and one of the most important symptoms in Osteoarthritis (OA), and due to its nature it is a debilitating feature of OA. However, joint pain is a late manifestation of this illness. But, in early stages of the disease, changes in joint structures can be observed, some of the most common being: formation of bony osteophytes, cartilage degradation and joint space reduction. Given that these characteristics are early symptoms of radiological OA, this study aimed to achieve an association between these radiological features and joint pain caused by OA. Using public data from the Osteoarthritis Initiative (OAI), a case-control study was performed, where a multivariate feature selection algorithm was used to determine a relationship between future joint pain and the radiological evidence of the disease. Subjects showing no evidence of pain at their baseline visit, no medication for pain, and no symptomatic status, were included in this study. Those who developed pain at a posterior time point were considered as cases, the rest as controls. Radiological information was evaluated using two different scores, one quantitative and one semi-quantitative, both assessed by OAI radiologist groups. The obtained models suggest that early joint structure changes can be associated with future joint pain. An image based biomarker that could predict future pain, measured in early OA stages, could become a useful tool to improve the quality of life of people dealing OA.