CT findings of tumor or tumor-like lesions in femoral neck

Objective To analyze the imaging appearance and to explore the diagnosis value of CT in tumor or tumor-like lesions of femoral neck.Methods Fifty-five cases with femoral neck lesions proved by operation and pathology were analyzed,and radiographic features were analyzed retrospectively.Results There were 11cases of osteoid osteoma,characterized by radiolucent nidus within the joint and bone sclerosis mainly in extra-articular areas.There were 8cases of giant cell tumors,characterized by eccentric,expanded bony destruction without obvious sclerosis in peripheral and calcification in the center area.After intravenous injection,obvious enhancement was seen.Bone metastasis(4cases)on the CT scan showed irregular,ill-defined lesion involving cortical destruction,with or without surrounding soft tissue.Multiple myeloma(2cases)appeared as single or numerous,lytic,well-circumscribed,round,punched-out lesions.Solitary bone cyst(8 cases)demonstrateed as well-defined,ovid or geographic lesions with thin sclerotic margins,and no enhancement.Aneurysmal bone cyst(2cases)appeared as sharply defined,centric,osteolytic lesions,with thin sclerotic margins and bone septations in the lesion,additionally.CT could demonstrate multiple cysts.There were 20cases of fibrous dysplasia,showing ageographic,well-defined,minimal expansion lesion,with ground-glass matrix andcloud of smokecalcification.Conclusion There is a huge range in the onset age and disease types in femoral neck lesions.Most have typical imaging characteristics,and some lesions need to be differentiated from others.