Table 2.

A scoring system was developed to assess synovial infiltration and morphogenesis at the peri-enthesis region shown in Fig. 4a–j. The composite scores are presented in Fig. 4k.

Peri-enthesis score
I. Synovial infiltration (0–3):
0	No infiltration with normal cartilage
1	Little synoviocyte infiltration and/or chondrocyte proliferation
2	Mild synoviocyte infiltration (replacing partial thickness of cartilage)
3	Severe synoviocyte infiltration (replacing full thickness of cartilage)
II. Morphogenesis (0–3):
0	No chondrogenesis by synovial cells; subchondral remodeling of articular surface
1	Isolated synovial chondrometaplasia; osseous encroachment beyond tidemark
2	Extensive synovial chondrometaplasia, with or without isolated ossification
3	Extensive ossification of synovial infiltrate with new haematopoiesis