Table 2.
Classification of histological score
| Characteristics | Staining | Classification | ||
|---|---|---|---|---|
| 1 | 2 | 3 | ||
| Disarray | H&E | Highly organized | Partially organized | Highly unorganized |
| Angiogenesis | α-SMA | Sporadic blood vessels | Several blood vessels | Numerous blood vessels in whole tissue |
| Fatty metaplasia | H&E | Absent | Focal | Extended |
| Hypertrophy of synovium | H&E | 1 layer | 2–3 layers | 4–5 layers |
| Immune cells | CD45 | Absent | Few immune cells mainly perivascular | Numerous immune cells inside the tissue |
| Accumulation of fibroblasts | H&E | Only fibrocytes (small, elongated nucleus) | Slightly increased number of fibroblasts | Greatly increased number of fibroblasts |
| Occurrence of villi | H&E | Absent | Focal | Extended |
| Chondral metaplasia | Alcian Blue | Absent | Focal | Extended |
| Nerve fibers | S100 | Absent | Few nerve fibers | Several nerve fibers |