QUESTIONS/PURPOSES: We therefore (1) determined which bone diseases most commonly mimic CAN; (2) what types of osteogenesis imperfecta (OI) are most commonly confused with CAN and why; and (3) what specific findings in OI and bone disease render a mistaken diagnosis of CAN more likely.
METHODS: A systematic review of the literature was performed. We identified studies that compared cases of CAN with cases in which patients had bone disease that resulted in an unexplained fracture. We also included studies in which patients with fractures resulting from underlying bony pathology were misclassified as CAN and were subsequently reclassified as bone disease as a result of further investigation. Our search netted only five studies that directly compared and contrasted CAN with metabolic or genetic bone disease in the same study.
RESULTS: The published literature suggests OI is most frequently confused with CAN, although metaphyseal dysplasia, disorders of phosphate metabolism, and temporary brittle bone disease are also documented in the literature identified by our search. Difficulty in differentiating these bony diseases from CAN stems from ambiguity in the history and physical examination at the time of presentation.
CONCLUSIONS: Bone disease is a diagnosis of exclusion in the differential diagnosis of CAN.