Effect of Triamcinolone Acetonide on Articular Cartilage

Intra-articular injections of glucocorticosteroids, including triamcinolone, remain controversial, despite the treatment’s inclusion in the guidelines for the management of patients with large joint osteoarthritis. Only a few trials studied the effect of triamcinolone on joint structure in vivo; however, most of the obtained results cannot be applied to patients with osteoarthritis. To determine the effect of a single, three and six weekly intra-articular injections of triamcinolone acetonide on articular cartilage and other joint structures. Fifteen rabbits were divided into three groups with a single, three, and six weekly intra-articular injections. Intact left knee joint of all rabbits was used as a control group. After euthanasia, a morphometric study of histological preparations of the joints was performed using a random-step morphometric grid by SB Stefanov. A single intra-articular injection had no negative effect on the knee joint morphology. Three weekly drug injections led to edema and microcirculatory disorders of the synovial membrane, minor degenerative, and necrotic changes but did not affect articular cartilage. Six injections with a 1-week interval led to pronounced aseptic destruction of the synovial membrane, slight decrease in cartilaginous lining thickness, and dystrophic-necrotic changes. Single and three weekly intra-articular triamcinolone injections into the rabbit knee joint (total dose equivalent to 120 mg for humans) did not have a chondrotoxic effect. Six weekly injections of triamcinolone (total dose equivalent to 240 mg for humans) led to severe synovial membrane destruction and to minor changes in the articular cartilage without affecting the subchondral bone.