Expansive changes in the ribs are a description of the condition of the ribs on CT examination. Most of the corresponding conditions are benign, and the common causes include fibrous dysplasia, bone cysts, and aneurysmal bone cysts. 1. Fibrous dysplasia: mainly benign tumor-like differentiation of fibrous bone tissue, the corresponding lesion is caused by the abnormal proliferation of fibrous bone tissue, resulting in expansive changes. 2. Bone cysts: the generation of the corresponding lesions is generally related to the abnormal blood reflux condition, which results in the accumulation of fluid in the bone tissue and further leads to the expansion of the bone. 3. Aneurysm-like bone cyst: it is related to the abnormal vascular condition or repeated blood seepage after trauma, and partly accompanied by the abnormal proliferation of giant cells, which further leads to the expansion of the bone. The presence of rib expansion changes, accompanied by pain or pathological fracture, need to consult a doctor in time for observation, after diagnosis of the condition under the guidance of the clinician to carry out standardized treatment, to avoid delaying the condition.