股骨颈关节囊内骨样骨瘤的临床及影像特点

Clinical and imaging features of intra-articular osteoid osteoma in the femoral neck

目的分析股骨颈骨样骨瘤的临床及影像特点，提高对本病的诊断水平。方法回顾性分析21例经手术病理证实的股骨颈骨样骨瘤的临床及影像学资料。其中男18例、女3例；年龄7。26岁，中位年龄13岁。所有病例均行常规X线及CT检查，其中同时行CT增强检查10例，行MR检查4例。结果19例表现为髋关节疼痛，其中夜间痛11例，8例服用水杨酸类药物可缓解；另外2例仅表现为跛行。病程2个月至4年6个月，中位时间12个月。X线平片：21例中仅有10例显示瘤巢，18例股骨颈内下方呈不同程度的骨质硬化。CT：21例均清楚显示瘤巢，其中骨皮质型8例，骨膜下型6例，骨内膜型7例；20例骨质硬化均位于瘤巢下方，即髋关节囊外的股骨前内侧骨皮质；“血管沟征”19例。MRI：4例均可显示瘤巢；骨质硬化在各序列上均呈低信号；关节积液3例，骨髓水肿4例，滑膜增厚2例。结论股骨颈骨样骨瘤的临床表现不典型，但其影像表现具有一定的特征性，瘤巢位于关节内，而骨质硬化主要发生于关节外的股骨前内侧骨皮质。CT扫描仍然是显示瘤巢的最佳方法。

Objective To evaluate the clinical and imaging characteristics of osteoid osteoma in femoral neck and to improve diagnostic accuracy of this disease. Methods Twenty-one patients （ 18 males and 3 females, age, 7-26 years, median age, 13 years） with pathologically proven osteoid osteoma of the femoral neck were retrospectively analyzed for their clinical profile and radiologic features. CT and X-ray examinations were performed in all patients, 10 of them performed post-contrast CT scan and 4 of them performed MRI examinations. Results Nineteen patients had hip pain （ pain worse at night in 11, and 8 received salieylates treatment with good response）, and 2 patients only with intermittent elaudieation. The duration ranged from 2 months to 54 months （median duration 12 months）. X-ray： Nidus was seen on plain film in 10 cases, 18 cases showed different degrees of bone sclerosis of the nidus. CT： Nidus was demonstrated in all cases. Among them, 8 were intracortical, 6 were subperiosteal, 7 were endosteal. Twenty cases showed different degrees of bone sclerosis of the nidus-extra-articular anteromedial cortical surface of the femur neck. Nineteen cases showed ＂vascular groove sign＂. MRI ： Nidus was seen in 4 cases. Bone sclerosis was low signal on all sequences. Three cases had joint effusion, 4 cases had bone marrow edema, and 2 cases had synovial thickening. Conclusions Although osteoid osteoma of femoral neck has non-specific clinical features, the radiographic findings are usually typical. The nidus of osteoid osteoma is often located within the joint. Bony sclerosis occurs at the area of extra-articular anteromedial cortical surface of the femur neck. CT examination remains an optimal method to identify the nidus.