Osteitis Condensans IliiDz

ICD-9 Code: 733.5.

Definition: Osteitis condensans ilii refers to an increase in bone density (sclerosis) located on the inferomedial aspect of the ilium adjacent to the sacroiliac joint. It is often bilateral, symmetric, and triangular. Sacroiliac and spinal a normalities (i.e., erosions) are not found.

Etiology: The cause is unknown. It may be owing to increased mechanical stress across the sacroiliac joint during pregnancy. It is usually associated with pregnancy but has also been reported in those with hydroxyapatite crystal deposition disease.

Demographics: It is primarily seen in young multiparous women.

Cardinal Findings: Only rarely are the radiographic findings symptomatic with pain.

Imaging: Radiographs show ill-defined ilial sclerosis that may resolve or persist.

Differential Diagnosis: Sacroiliitis and AS characteristically affect the sacroiliac joint with erosions, pseudowidening, or ankylosis. Degenerative changes in the sacroiliac joint may be confused with osteitis condensans ilii.

Therapy: None is indicated.