A study of repair cartilage from osteochondrotic humeral condyles of swine: preliminary report.

A total of 16 animals, including 12 lame and four normal boars, were used. All lame boars had severe osteochondrotic humeral condyles in which repair cartilage tissues originating from subchondral bone were observed. Quantitative chemical studies of repair cartilage and normal cartilage were carried out using humeral condyles from four selected animals (two lame and two normal boars, respectively). The repair cartilage contained a higher concentration of collagen and lower concentration of proteoglycan than did the normal cartilage, consistent with the light microscopic observation of fibrous and fibrocartilaginous tissues in the repair cartilage. The proportion of proteoglycan extractable with 4M-guanidine hydrochloride was less in the repair cartilage than the normal cartilage. The proportion of proteoglycan that can interact with hyaluronic acid was also less than normal in the repair cartilage.