With the Dumonde-Glynn model of antigen-induced arthritis, a rabbit model was developed to examine the histopathologic differences between normal and arthritic joints in the same animal infected by intraarticular injections of Staphylococcus aureus. Microscopic examination of whole joint sections and a quantitative histopathologic scale were used to compare changes in all the articular components of 17 normal and 17 arthritic joints infected for less than two weeks. The histological changes were more severe in infected arthritic joints than in infected normal joints (mean ± SD total histology score, 13.8 ± 2.4 and 9.3 ± 4.0, respectively; P <.001). In infected arthritic joints, subsynovial abscesses extended into subchondral bone via the pannus of chronic synovitis at articular margins and intraarticular attachments of cruciate ligaments, rather than by initial cartilage destruction and direct extension into subchondral bone.
Bibliographical noteFunding Information:
Received for publication 30 September 1985,and in revised form 18 February 1986. This work was supported by funds from the Veterans Administration and by a grant from the Minnesota Arthritis Foundation. We thank Drs. Frank Schmid and George A. Sarosi for suggestions and encouragement. Please address requests for reprints to Dr. Maren L. Mahowald, Rheumatology Section, V.A. Medical Center, 54th Street and 48th Avenue South, Minneapolis, Minnesota 55417. * Present address: Department ofMedicine, The Mary Imogene Bassett Hospital, Cooperstown, New York.
Copyright 2016 Elsevier B.V., All rights reserved.