Hand function depends on tendon integrity, but in rheumatoid arthritis tenosynovitis can result in tendon adhesions and rupture. Cytokine inhibitors have proved effective in rheumatoid joint disease; however, their effect on the tenosynovium is not well understood. We investigated the ability of inhibitors of tumour necrosis factor alpha and interleukin 1 to reduce production of collagenolytic matrix metalloproteinases 1 and 13 in tenosynovial tissue obtained from patients with rheumatoid arthritis. Our data show that cytokine blockade can reduce collagenase concentrations in tenosynovial tissue, suggesting cytokine inhibitors could be effective in reduction of tendon damage.