From: Cellular and molecular meniscal changes in the degenerative knee: a review
MENISCUS: normal knee | MENISCUS: degenerative knee | |
---|---|---|
Gross anatomy | Translucent, smooth and glistering | Dark yellow to brown or reddish color, roughened and fibrillated surfaces |
Cell population | 0.12% of the meniscus weight (around 98 cells per 0.1 mm2) | Decreased |
Proliferating cells | Frequently observed | Almost absent |
Necrosis and apoptosis | Almost absent | Frequently observed |
Cells clusters | Exceptionally | Frequently observed |
Calcification | No | Frequently observed |
Collagen | Dense framework of collagen fibers. Type I (90%) | Reduced and disrupted or fragmented |
Proteoglycans | < 1% and 80% sulfated | Initially increases. Tend to decrease in advances stages |
COMP | High amounts. Same heterogeneous distribution than cells, decreasing from the red to the white zone | Decreased |