Table 1.
Cause | Mechanism | Reversible? |
---|---|---|
Osteoarthritis | Proteolytic degradation of matrix | No, except by regeneration |
Atrophy | Reduced synthesis of proteoglycan; a mechanoadaptive response to reduced load | Yes, weeks–months |
Cartilage compression | Water extrusion from matrix due to compression | Yes, minutes–hours |
Apparent reduction in joint space (‘pseudo thinning’) | Migration of tidemark or meniscal extrusion | Unknown |