Plasma glycosaminoglycans in experimental osteoarthritis caused by immobilization.

The right knees of adult rabbits were immobilized under conditions known to produce either "developing" osteoarthritic lesions or advanced, "chronic" lesions typical of osteoarthritis. The concentration of plasma glycosaminoglycans was assayed and found to be unchanged in "developing" osteoarthritis but significantly increased in animals with "chronic" lesions of the immobilized knee. Assays of plasma glycosaminoglycans may be useful in the assessment of osteoarthritis.