An enthesis (pl. entheses) is the connective tissue junction where ligaments and tendons attach to bone.
There are two types of entheses:
- fibrous enthesis
- fibrocartilage enthesis
The ligament or tendon attaches directly to the bone.
There is a more complex attachment:
- tendon with longitudinal fibroblasts
- fibrocartilaginous region of variable thickness where chondrocytes predominate
- abrupt transition to calcified fibrocartilage (the tidemark, or blue line)