Complete Fusion of Three Lumbar Vertebral Bodies in Ankylosing Spondylitis.

Ankylosing spondylitis is a seronegative arthropathy of unknown etiology affecting mainly young adults. Acute or chronic changes of the spine such as sacroiliitis, spondylodiscitis, osteitis, ossification, and arthropathic lesions characterize the disease. Spinal involvement may accompany ossification of the ligaments, disc, end-plates and apophyseal structures, and seems to be bamboo spine. Here, we report a rare case describing the complete fusion of three lumbar vertebral bodies in ankylosing spondylitis. This rare case is presented alongside a literature review.