Is there a correlation between biophotonical, biochemical, histological, and visual changes in the cartilage of osteoarthritic knee-joints?

The aim of this study was to detect characteristic structural changes in the cartilage composition of osteoarthritis (OA), hereby improving the arthroscopic identification of cartilage pathology by the use of a non-destructive technique - NIRS (Near-Infrared Spectroscopy). 682 cartilage samples out of 25 knees with OA were classified visually, using the ICRS system, biophotonically, histologically (n = 66), using the Score of Mankin and the Score of Otte, and biochemically (n = 616), determining the content of glycosaminoglycan (GAG) and hydroxyproline (HP). Significant correlations were found between biophotonical, histological, biochemical and visual characteristics of cartilage lesions.

BMP-2 shows characteristic extracellular patterns in osteoarthritic cartilage: a preliminary report.

To determine bone morphogenetic protein (BMP)-2 protein and Aggrecan in osteoarthritic and healthy cartilage with special regard to localization and degree of cartilage damage 95 samples representing osteoarthritic cartilage and 17 samples out of normal cartilage were graded histological by Mankin Score and were studied by immunohistochemistry for the expression of BMP-2 and Aggrecan. BMP-2 protein was detected intracellular in normal and in osteoarthritic cartilage. Extracellular BMP-2 was detected exclusively in osteoarthritic cartilage and exhibits characteristic extracellular patterns: samples with BMP-2 in the extracellular matrix show BMP-2 negative coronae around BMP-2 positive cells.