Effector chondrocytes

This likely refers to chondrocytes in a state of active matrix degradation or inflammation, analogous to "effector" immune cells. In osteoarthritis or rheumatoid arthritis, some chondrocytes adopt a catabolic phenotype, expressing enzymes like matrix metalloproteinases (MMPs) and aggrecanases (ADAMTS) that break down the cartilage extracellular matrix, contributing to joint destruction.