Bisphosphonates--targeting bone in the treatment of spondyloarthritis.

The increased prevalence of osteoporosis and recognition of the importance of subchondral bone marrow inflammation in ankylosing spondylitis, together with in vitro and animal model data indicating that bisphosphonates may possess anti-inflammatory properties, constitute a theoretical rationale for their evaluation in this disease. Open evaluation of intravenous pamidronate in some but not all studies has demonstrated efficacy whilst controlled evaluation of a monthly regime has shown that therapy is efficacious in about 60% of patients, although effects are delayed, treatment being necessary for at least 6 months.