| MadSci Network: Development |
(Q1) Articular cartilage (found in joints) "grows" by the action of cells called chondrocytes. These cells are more abundant in the cartilage in younger ages but are much mnore sparse in adults. Articular cartilage does not repair very well since the chondrocutes are so few, they have a very low rate of reprodcution, and they are nutritionally limited (poor blood supply so the joint fluid provides necessary nutrition). A recent study by NIH demonstrated glucosamine and/or condroitin sulfate was no better than placebo in reducing knee pain due to osteoarthritis. (New England Journal of Medicine 354:795-808, 2006) (Q2) If an injury occurs, the body may be able to repair it with additional hyaline cartilage, but only a very small injury and only if the calcified plate is not been breaced. Otherwise, fibrocartilage will form in the defect after inflammation. This fibrocartilage may be improved with joint motion. (Q3)Epipheaseal plates have more to do with bone length than articular cartilage. At the time that the last plates have fused, the person is likely about 20 years old so the cartilage cells are sparse (see Q1). Not sure to what cartilage you refer between shin and femur (?knee joint) Spine disks contain fibrocartilage. These comment are not meant to provide specific individual medical advice.
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