例１，女，２０岁，左小腿上端肿痛４～５月，曾有外伤史。Ｘ线平片：左胫骨上端内侧见一偏心性膨胀性卵圆形透亮区，大小约５ｃｍ×３ｃｍ，其内可见骨嵴，有硬化边，与正常骨组织分界清楚，无骨膜反应及软组织肿块（图１）。诊断：左胫骨上端良性骨肿瘤（非骨化性纤维瘤... Case 1, female, 20 years old, upper left leg swelling and pain from April to May, had a history of trauma. X-ray film: The left side of the medial side of the left tibia sees an eccentric, expansive, oval, translucent region of about 5 cm x 3 cm in size. Bone hernias are visible inside. There are sclerotic edges. The boundaries between the bone and the normal bone tissue are clear. There is no periosteal reaction and soft tissue mass. (Figure 1). Diagnosis: benign bone tumor of the upper left tibia (non-ossifying fibroma...