The following sets of X-rays are suggestive of:
A. Ankylosing spondylitis
B. Paget’s disease
C. Rheumatoid arthritis
Ans: A. Ankylosing spondylitis
(Ref: Harrison 19Ie p2170, 18Ie p2775; Apley’s 9/e p68)
Earliest cardinal sign:
- Erosion and fuzziness of the sacroiliac joints.
- Peri-articular sclerosis, especially on the iliac side of the joint and finally bony ankylosis.
Earliest vertebral change:
- Flattening of the normal anterior concavity of the vertebral body (`squaring’).
- Later, ossification of the ligaments around the intervertebral discs produces delicate bridges (syndesmophytes) between adjacent vertebrae.
- Bridging at several levels gives the appearance of a ‘bamboo spine’.