Osteitis Condensans Ilii: A Comprehensive Case Series of Five Patients with Radiological Insights and Differential Diagnosis

Background: Osteitis Condensans Ilii (OCI) is a rare, benign skeletal condition characterized by sclerosis of the iliac bones adjacent to the sacroiliac (SI) joints. It is often misdiagnosed as sacroiliitis or degenerative SI joint disease. OCI primarily affects women of reproductive age and is associated with chronic lower back pain. Objective: This case series aims to highlight the clinical presentation, imaging features, and management of OCI in five patients. We also explore the radiological challenges in differentiating OCI from other sacroiliac joint pathologies. Methods: A retrospective review of five female patients diagnosed with OCI was conducted. Clinical histories, radiological findings (X - ray, CT, MRI), differential diagnoses, and management strategies were reviewed. Results: The patients presented with chronic lower back pain. Radiological findings revealed bilateral symmetrical sclerosis of the iliac bones, sparing the sacrum and SI joint spaces. All patients underwent conservative management with physiotherapy and NSAIDs, resulting in symptomatic relief. Conclusion: OCI is a self - limiting, benign condition that requires accurate radiological differentiation from other inflammatory and degenerative sacroiliac joint diseases. Early recognition through imaging is key to avoiding unnecessary treatments and improving patient outcomes.