Simple Bone Cyst involving Proximal Epiphysis of the Humerus: A Case Report

Simple or unicameral bone cysts are metaphyseal lesions of long bones. They usually move away from the physiswith growth to become diaphyseal in location. Involvement of the physis and epiphysis by these cystic lesions isvery rare. This paper reports a case of simple bone cyst of the proximal humerus in a 11- year -old girl which wasshown by MR imaging to extend through the physis into the epiphysis.

Simple Bone Cyst: Radiologic Changes after Injection of Steroid

PURPOSE: To evaluate radiographic changes and clinical effects after the injection of steroid injection into simple bone cyst. MATERIALS AND METHODS: We analyzed plain radiographic and CT findings after the injection of steroid (methylprednisolone acetate, MPA) into simple bone cyst. Twelve patients were involved; eight were males and four were females, and their ages ranged from 6 to 41 years. They were treated from one to seven times with an intracystic injection of MPA, 80-200mgs per injection. All patients were evaluated by plain film, and four by CT, and the mean follow-up period was 20 months. RESULTS: Postinjection plain radiographic findings were as follows: increased internal radiodensity (n=10), smaller cyst (n=8), cortical thickening (n=7), and radiodensity of double ring pattern (n=4). CT findings were as follows: increased internal attenuation (n=4), smaller cyst (n=4) and radiodensity of double ring pattern along the cyst wall (n=4). All patients improved clinically and radiologically, especially those with radiodensity of double ring pattern. CONCLUSION: The injection of steroid into simple bone cyst is an effective treatment. A new radiographic finding after injection is radiodensity of double ring pattern along the cyst wall, and we believe that this indicates progression of the healing process.