Biological therapies should be considered in patients with high disease activity despite nonsteroid antiinflammatory drug treatment. The first option among biological therapies is anti-Tumor Necrosis Factor (anti-TNF) drugs. In recent years, anti-TNF treatments have shown that clinical and ultrasonographic enthesitis may improve as well as disease activity, quality of life and acute phase reactants. In this prospective study, we aimed to evaluate the clinical and ultrasonographic evaluation of enthesitis and to determine its response to anti-TNF treatment in patients with SpA.In this prospective study, we aimed to evaluate the clinical and ultrasonographic evaluation of enthesitis and to determine its response to anti-TNF treatment in patients with SpA.

Inclusion Criteria:

• Spondyloarthritis patients were diagnosed according to 2009 Assessment of Spondyloarthritis International Society (ASAS) criteria

Exclusion Criteria:

• Severe cardiovascular and respiratory diseases,
• Severe liver and kidney failure,
• Pregnancy and lactation,
• Active infection,
• Malignancy,
• Demyelinating diseases,
• Systemic lupus erythematosus,
• History of knee, elbow, foot and ankle surgery,
• Fluoroquinolone, retinoid and fluoride use,
• Local corticosteroid injection at the examination sites within the six weeks before evaluation
• Peripheral neuropathy

All patients were evaluated by the researcher who had a 10-year experience of musculoskeletal ultrasonography and is blind to clinical evaluation.