Premium
A capsular incision leads to a fast osteoarthritic response, but also elevated levels of activated osteogenic protein‐1 in rabbit knee joint cartilage
Author(s) -
Fahlgren A.,
Chubinskaya S.,
Messner K.,
Aspenberg P.
Publication year - 2006
Publication title -
scandinavian journal of medicine and science in sports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.575
H-Index - 115
eISSN - 1600-0838
pISSN - 0905-7188
DOI - 10.1111/j.1600-0838.2005.00513.x
Subject(s) - medicine , osteoarthritis , cartilage , articular cartilage , surgery , knee joint , subchondral bone , immunohistochemistry , pathology , anatomy , alternative medicine
We studied whether a small capsular incision alone, or combined with meniscectomy could induce early osteoarthritic changes in the rabbit knee. Thirty‐one rabbits were operated on with a capsular incision in the left knee and meniscectomy in the right knee. Another 12 rabbits were used as controls. The rabbits were killed 3, 6 and 12 weeks after surgery. Osteoarthritic changes in the articular cartilage were evaluated by the modified Mankin score. The subchondral bone was evaluated by scintimetry ( 99m Tc‐HDP) and semiquantitative grading of histological changes. Osteogenic protein (OP‐1) in its mature and pro‐form was examined by immunohistochemistry. Both a capsular incision and meniscectomy induced articular cartilage fibrillation and increased bone metabolic activity during the initial weeks after surgery. Capsular incision led to lesser changes than meniscectomy. Mature OP‐1 was elevated, and its pro‐form reduced, in meniscectomized knees. A similar pattern was observed in knees with capsular incision. Already 3 weeks after surgery, the articular cartilage and subchondral bone showed typical signs of early osteoarthritis (OA), and a reparative response was suggested by increased intensity of OP‐1 staining. As these signs were also found in knees with capsular incision only, it appears that trauma‐related factors such as increased bleeding and inflammation are critical for the development of OA.