Presentation
Pelvic and low back pain.
Patient Data

Bilateral iliolumbar ligament calcification is seen.
Subchondral sclerosis and joint space narrowing of the weight-bearing areas of both hip joints are evident, accompanied by small marginal osteophytes. A focal ill-defined soft tissue ossification is noted lateral to the right hip joint.
In addition, degenerative changes, including subchondral sclerosis and irregularity, are seen in the pubic symphysis.
Case Discussion
The iliolumbar ligaments originate from the transverse processes of the fifth lumbar vertebra and extend laterally and posteriorly to the iliac crest, attaching to the anterior and posterior margins of the iliac crest, respectively.
Diffuse ossification of the iliolumbar ligaments is usually an incidental finding, commonly seen in degenerative disease and diffuse idiopathic skeletal hyperostosis (DISH), but it can be associated with seronegative spondyloarthritis.