Figure 5.

Summary of properties of human articular cartilage related to biomechanical deterioration with aging²,³ and osteoarthritis. Histological depiction of mechanical integrity (degree of gray shading), articular surface fibrillation, chondrocyte density, collagen network alteration (fragmentation of fibrils and decrease in intrinsic fluorescence), and loss of GAG (▨) are shown. Tabulated are location of changes, superficial tangential zone (STZ), middle zone (MZ) and deep zone (DZ), denoted by • or (•) for variable changes. Absence (○) or full presence (●) of parameters are indicated under stages noted, with changes indicated by ➞.