Increased Chondrocyte Death after Steroid and Local Anesthetic Combination

Background Hyaline articular cartilage has limited repair and regeneration capacity. Intraarticular administration of glucocorticoid and local anesthetic injections play an important role in the therapy of osteoarthritis. Glucocorticoids and anesthetics reportedly enhance apoptosis in chondrocytes, but effects of the combined use of glucocorticoids and local anesthetics are unknown. Questions/purposes We asked whether glucocorticoid and local anesthetic agents combined had any synergistic effects on chondrocyte apoptosis. Methods Cell viability and apoptosis/necrosis assessment of human articular chondrocytes were performed in vitro (chondrocyte cell cultures) and ex vivo (osteochondral specimens) using flow cytometry and TUNEL analysis, respectively. Results Glucocorticoids and local anesthetics induce apoptosis in chondrocytes at various rates. When used in combination, the percentage of dead chondrocytes was increased in in vitro chondrocyte cell cultures and osteochondral ex vivo specimens. Conclusions We observed a time-dependent decrease in chondrocyte viability after concurrent steroid and local anesthetic exposure. Clinical Relevance The combination of glucocorticoids and local anesthetics has an adverse effect on articular chondrocytes, and it raises a question regarding whether concomitant administration should be used in treating osteoarthritis.