- Enthesis
Enthesis (plural: entheses) is the point at which a
tendon orligament [Medcyclopaedia|iii_1/e/enthesis] ormuscle [DorlandsDict|three/000035780|enthesis] inserts intobone , where thecollagen fibers are mineralized and integrated into bone tissue. These insertion points are commonly calledSharpey's fibers .Classification
There are two types:
* Fibrous entheses
* Fibrocartilaginous enthesesIn a fibrous enthesis, the collagenous tendon or ligament directly attaches to the bone, whilst the fibrocartilaginous enthesis displays 4 zones during the transition from tendon/ligament to bone:
* i) tendinous area displaying longitudinally oriented fibroblasts and a parallel arrangement of collagen fibres
* ii) a fibrocartilaginous region of variable thickness where the structure of the cells changes to chondrocytes
* iii) an abrupt transition from cartilaginous to calcified fibrocartilage - the so-called 'tidemark' or 'blue line'
* iv) bonePathology
A disease of the entheses is known as an "
enthesopathy " or "enthesitis" and is characteristic ofspondyloarthropathy but present in other pathology as well.References
External links
* [http://images.medscape.com/pi/editorial/cmecircle/2004/2890/images/slide13.gifImage of enthesis] at
Medscape
* [http://www.chiroweb.com/archives/18/19/23.html Enthesopathy and Soft Tissue Shadows] at chiroweb.com
*
* [http://www.rheuma21st.com/archives/report_khan_2int_enthesitis_meet.html Origin of phrase at rheuma21st.com] at rheuma21st.com
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