分析老年腓骨近端骨肉瘤影像表现，总结腓骨近端骨肉瘤的影像学诊断特点和鉴别诊断要点。

回顾分析2004年1月至2016年12月经病理证实的6例腓骨近端骨肉瘤的X线、CT和MRI，分析影像学表现，包括：肿块的形态、骨质破坏情况、病变内的骨质密度、骨膜反应及周围侵犯范围等。

6例患者中，男性4例，女性2例，年龄为50岁~72岁。溶骨型2例，混合型3例，成骨型1例；发生在骨端的为2例，干骺端的4例。6例患者仅2例有骨膜反应，其中1例为Codman三角，1例为平行状骨膜反应，发生在骨端的骨肉瘤未发现骨膜反应。MRI表现T1WI为中、低混杂信号，T2WI呈高、低混杂信号，6例患者均有软组织肿块。

老年人腓骨近端骨肉瘤以混合型为多见，Codman三角和骨膜反应少见，特别是位于骨端的骨肉瘤。溶骨型骨肉瘤无骨膜反应时，需注意与好发于腓骨骨端的骨巨细胞瘤和软骨母细胞瘤等良性肿瘤相鉴别。

To analyze the imaging features of the proximal fibula osteosarcoma and summarize its imaging diagnosis characters and differential diagnosis in this region.

Retrospectively analyzed the X-ray, CT and MRI of 6 cases of proximal humerus osteosarcoma were confirmed by pathology from January 2004 to December 2016, and analyzed the imaging findings, including the shape of the tumor, the destruction of the bone, and the bone of density in the lesion, density, periosteal reaction and range of encroachment.

There were 4 males and 2 females, aged from 50-72 years old. There were 2 cases of osteolytic type, 3 cases of mixed type, and 1 osteogenic type. Two osteosarcoma occurred at epiphysis and 4 occurred at metaphysis. Only 2 of 6 patients had periosteal reaction, of which 1 was Codman's triangle and 1 was parallel periosteal reaction. No periosteal reaction was found in bone-end osteosarcoma. MRI, T1WI showed moderate and low mixed signals, T2WI showed high and low mixed signals, and 6 patients had soft tissue lumps.

The mixed type was more common in osteosarcoma in the proximal end of fibula. The radial periosteum reaction and Codman triangle were rare, especially osteosarcoma located at the bone end. Osteolytic osteosarcoma without periosteal reaction should be distinguished from benign tumors such as giant cell tumors and chondroblastomas that occur at the ends of the fibula.