A 56-year-old overweight patient complains of pain in her knee joints. The pain intensifies when she walks, climbs stairs, or remains standing for a long time. The disease onset was 5 years ago. Objectively, the knee joints are deformed, edematous, and painful during movements. X-ray of the knee joints shows joint space narrowing, subchondral sclerosis, and marginal osteophytes. What is the most likely diagnosis in this case?