these arthritides may be distinguished from each other by a number of clinical and radiographic characteristics , principally ( 1 ) the roentgenographic appearance of the spine when spondylitis is present , ( 2 ) the location of periosteal new bone formation , ( 3 ) the location of arthritis in the joints of the limbs , and ( 4 ) the presence of characteristic skin lesions .
C0038012
spondylitis
C0003864
arthritis