[Spinal claudication and malum perforans pedis. Late sequela of ankylosing spondylitis (Bechterew disease) with cystic lumbosacral arachnopathy].

Enlargement of the caudal sac with bony erosions of the spinal vertebrae may be a late sequel of ankylosing spondylitis. CT scans demonstrate typical changes. We report a case with spinal claudication and a neuropathic ulcer.