NGF and bone disorder: Based on analyses of associations between NGF expression and osteoclast density with subchondral bone cysts, MTP bone with cysts had a significantly higher percentage of NGF-positive area and channels, as well as greater osteoclast density, compared to MTP bone without cysts (NGF-positive area and channel: p ​< ​0.01, osteoclast density: p ​< ​0.05).