BGN and osteoarthritis: Since biglycan (BGN) and FMOD display a complementary role in various physiological and pathological processes, the mice with the absence of Bgn and Fmod successively developed gait impairment, ectopic tendon ossification, and severe premature osteoarthritis including cartilage degeneration and damage at an early stage (between 1 and 2 months), and its progression was very rapid (complete erosion of the articular cartilage between 3 and 6 months) (120).