Answer to Question 1
The word chondral refers to cartilage. Subchondral bone is that portion of bone that sits just below the cartilage. As OA progresses, subchondral bone stiffens and undergoes infarction. Cartilage breaks down and is gradually destroyed. Bone-on-bone contact develops in advanced disease. Without the protection of the cartilage, cysts, scar tissue, and osteophytes form at the joint margins
Answer to Question 2
Disease entities named for an individual (eponym) do not take the possessive form but other terms used as descriptors follow Standard English grammar rules and do still take the possessive form. The American Medical Association adopted the non-possessive style of writing eponyms to promote consistency and clarity.