Osteitis Condensans Ilii

Muscle strain of the back was the chief complaint of a 28-year-old woman who presented to the emergency department. A radiograph of the lumbar spine revealed sclerosis in both sides of the sacroiliac joint, without space narrowing.

Although its exact cause is unknown, osteitis condensans ilii is believed to result from mechanical stress across the sacroiliac joint. This benign condition is usually symmetrical.

Multiparous women are most commonly affected; osteitis condensans ilii typically occurs after pregnancy and does not seem to affect future
pregnancies. The condition may resolve with time, but osteoarthritis and cyst formation may follow.

This patient was given paracetamol, and she responded very well.