A 25 year old man presents to your clinic with low back pain that improves with exercise but not rest. It had an insidious onset and occurs at night. He also has buttock, hip, shoulder, TMJ, and posterior thigh pain. He had an episode of anterior uveitis a month ago. Review of systems is notable for fatigue.
Physical exam is remarkable in that the patient is stooped; you note loss of normal lumbar lordosis, increased flexion of the neck, and increased thoracic kyphosis.
Challenge: What's your diagnosis?
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