About the MOST Study

Knee osteoarthritis (OA) is a common chronic painful disorder that is the most frequent cause of mobility disability in aging adults. The prevalence of OA is increasing due to aging and increased rates of obesity. Currently there are few effective treatments for OA none of which slows disease progression.

The Multicenter Osteoarthritis Study (MOST) is one of the world’s longest running cohort studies of OA. Initially funded in 2001, the MOST study has been a major source of new knowledge about the course of OA and factors that affect it. Having published over 180 articles on pain and pain sensitivity, biomechanics, structural joint pathology, decline in function, and falls; results from the MOST study has provided insights into risk factors and consequences of this highly prevalent and disabling disease.

The MOST study is now in its fourth cycle (MOST4) with an overall goal to advance our understanding of OA and its consequences in order to advance treatment approaches including stratified approaches. Specifically, this project will examine the neurobiological mechanisms related to impaired exercise-induced hypoalgesia (temporary reduction in pain and sensitivity to pain that occurs with exercise) in people with knee OA, identify proteins in knee OA synovial fluid and plasma that are associated with pain and disease progression of OA, and differentiate types of calcium crystals deposited in the knee to further understand the clinical and structural consequences of crystal deposition.

To achieve these goals previous MOST study participants will be invited to participant in MOST4. Furthermore, 150 new participants will be recruited with a projected total of 2,293 participants. All participants will be invited to two clinic visits approximately 24 months apart and interim electronic contacts every four months. This new cycle of the MOST study will continue to collect measures that will permit comprehensive evaluation of OA status and outcomes, including longitudinal profiles of self-reported pain and function, and performance-based function.