Strikingly, the distal interphalangeal (DIP) and PIP joints were intact, and hook-like osteophytic
formations on the heads of the metacarpal bones were seen, which is typical of hemochromatosis.
Grade I represents minor osteophytic lipping, while grade IV demonstrates end-stage changes, with severe joint space narrowing, sclerosis, and change in bony contour.
Table 1 Kellgren-Lawrence Arthritis Grading Scale * Grade Characteristics I Doubtful joint space narrowing, possible osteophytic lipping II Definite osteophytes, definite joint space narrowing III Moderate multiple osteophytes, definite joint space narrowing, some sclerosis and possible deformity of bone contour IV Large osteophytes, marked joint space narrowing, severe sclerosis and deformity of bone contour * (Adapted from: Kellgren JH, Lawrence JS.
Therefore, we focused on the distribution of PEDF within different human cartilaginous tissues of different developmental stages that are subjected to endochondral ossification, including the fetal epiphysis, the postnatal growth plate, and adult articular and osteophytic cartilage.
Osteophytic cartilage (OC), as well as periosteal mesenchyme (PM) and subchondral bone (B), were isolated from osteochondral samples of the same respective joints originating from the edges of the femoral condyles.
For protein isolation and mRNA-analysis, articular cartilage, osteophytic cartilage, periosteal mesenchyme, and bone were dissected and isolated.
The quantitative gene expression analysis of the corresponding tissues reflects the pattern of immunohistochemistry, with strong PEDF mRNA expression in osteophytic cartilage (OC), bone (B), and periarticular mesenchyme, but virtually no PEDF mRNA expression in healthy articular cartilage (AC) (Figure 1(d)).
Immunohistochemical analysis demonstrated a corresponding staining pattern of MMP13 to that of PEDF, which was observed in the zone of endochondral ossification in human epiphyseal cartilage, growth plate cartilage, and osteophytic tissue.
Ekicietal., "The transient chondrocyte phenotype in human osteophytic cartilage: a role of pigment epithelium-derived factor?" Cartilage, vol.