Ankylosing Spondylitis: Features

Key points

• Ankylosing spondylitis is a HLA-B27 associated spondyloarthropathy. It typically presents in males (sex ratio 3:1) aged 20-30 years old. Features
• typically a young man who presents with lower back pain and stiffness of insidious onset
• stiffness is usually worse in the morning and improves with exercise
• the patient may experience pain at night which improves on getting up Clinical examination
• reduced lateral flexion