Table 1

Similarities and differences between normal tendon, fibrocartilage and tendon pathology58

Normal tendonFibrocartilagePathological tendon
CellsFew spindle–shaped cellsNo cell proliferation
Cells rounder		Cell proliferation
Cells rounder, more endoplasmic reticulum
ProteoglycansMinimal mostly decorin and biglycan5–10 times more than in tensile tissue, mostly aggrecan3 times more than tensile tissue, 25x metabolic rate of normal tendon11 Biglycan and aggrecan increase, decorin maintained8
CollagenPredominately type IType I and IIType I collagen, some type II, substantial increase in type III collagen
Collagen structureOrdered collagen networkOrdered collagen networkDisorganised collagen network
VascularityMinimalNone to minimalVariable but can be abundant