Frontal abdominal CT scan, slice of the spine.
This patient has been suffering from Crohn's disease for years. He was operated on a tumor of the sigmoid in 2007, when the disease was diagnosed at age 40. Since then, he's been under cortisol treatment, and later under azathoprin and mesalazine. 3 days ago, he got an ileus of the small intestines.
On this CT scan, you can see a typical extraintestinal manifestation of Crohn's disease: (seronegative) spondylarthropathy.
Frontal CT scan 2
Frontal CT scan 3
Sagittal CT scan