BICL’s Dr. Roemer and colleagues this week published an overview of the state of the art of structural phenotype research in OA that is highly relevant to clinical trial design of DMOAD programs. A treatment for OA that targets only one pathophysiologic abnormality is unlikely to be similarly efficacious in preventing or delaying the progression of all the different phenotypes of structural OA. Based on this assumption Dr. Roemer and his colleagues recently described five structural phenotypes, namely the inflammatory,meniscus-cartilage, subchondral bone, and atrophic and hypertrophic phenotypes. The inflammatory phenotype is characterized by marked synovitis and/or joint effusion, while the meniscus-cartilage phenotype exhibits severe meniscal and cartilage damage. Large bone marrow lesions characterize the subchondral bone phenotype. The hypertrophic and atrophic OA phenotype are defined based on the presence large osteophytes or absence of any osteophytes, respectively, in the presence of concomitant cartilage damage. Structural phenotypic stratification may result in more targeted trial populations leading to successful outcomes. Practitioners should be aware of the heterogeneity of the disease to personalize their treatment recommendations for an individual patient. The article is available at Skeletal Radiology or here: