Bone cysts are usually diagnosed by X-ray, and magnetic resonance can also be diagnosed, but not always need to do magnetic resonance. Bone cysts are slow-growing benign bony lesions that occur in the metaphyses of long bones. They usually have no conscious symptoms, and most cases are detected by X-ray when a pathologic fracture occurs. Bone cysts appear on X-ray as osteolytic lesions with thinning and swelling of the cortex without any periosteal reaction in the surrounding area. The most important feature is that the lesion never penetrates the bone cortex or enters the soft tissue. In individual cases where the diagnosis cannot be confirmed by X-ray, further MRI can be done, which can show characteristic damage.