• Biochemical architecture and regulation of cartilage matrix dominated by proteoglycan–glycosaminoglycan interactions; studies traced non-collagenous proteins, chondroitin sulfate–protein complexes, and their alkali/dissociation behavior, revealing a distinct protein–polysaccharide scaffold beyond collagen and its modulation by enzymatic and chemical treatments [1], [2], [5], [8], [16], [15].

• Mechanical loading and surface injury drive degenerative remodeling in articular cartilage, with persistent pressure causing fibrillation, chondrocyte death, eburnation, and bone cysts; scarification alters matrix synthesis near damaged zones, highlighting a stress-driven degenerative trajectory across rabbit and human cartilage [6], [19], [18], [7].

• Enzymatic interventions reveal natural cartilage matrix vulnerability and remodeling pathways, with papain-mediated matrix removal in vivo, papain depletion increasing in vitro radiolabel uptake, plasmin action on cartilage, and intracellular proteases as potential drivers of matrix degradation under vitamin A excess [4], [14], [9], [12].

• Chondrocyte biology and ultrastructure studies map cell-level responses to injury, aging, and matrix perturbations, including mitosis in adult rabbit articular cartilage, in vitro sulfate uptake by chondrocytes, and electron microscopic observations of Golgi and collagen in cartilage, signaling a shift from matrix-centric to cell-centric degeneration understanding [13], [3], [11].

• Pathology-driven degeneration framing osteoarthritis and septic/articular inflammatory contexts, including osteoarthritis of the hip, destruction in septic arthritis, and age-related cartilage decline, revealing clinical-degenerative trajectories and their matrix and cellular correlates [18], [10], [7].