TNF and ankylosing spondylitis: The keywords used for the search were “TNF alpha inhibitors”, “anti TNF-a”, “TNF-a inhibitors”, “anti TNF-alpha”, “Etanercept”, “Golimumab”, “Infliximab”, “Certolizumab pegol”, “Adalimumab”, and “ankylosing spondylitis”. The primary search included 2257 articles.