邻关节骨囊肿的影像诊断

目的 探讨邻关节骨囊肿(骨内腱鞘囊肿)的影像表现特征.方法 对经病理证实的54例邻关节囊肿影像表现进行回顾性分析.46例行X线平片检查,30例行CT检查,14例行MR检查.结果 54例邻关节骨囊肿位于踝关节27例(含多发),膝关节16例,髋关节7例,位于肱骨近端、尺骨近端、大多角骨及第1趾骨近节近端各1例;其中多发1例(距骨和胫骨远端).病变位于踝关节及膝关节共43例44个病变,其中位于内侧关节而下29个病变(65.9%).44例为类圆形单房状溶骨病变,10例呈多房状,内有分隔,均有轻度的硬化边.15例关节面有中断,与关节腔相通,1例关节面塌陷,3例病变内见气体密度,1例见液.液平面.具体为:(1)46例47个病灶x线表现为骨内邻近关节面的圆形、半圆形或不规则囊样透亮区,边缘清晰、硬化,6个病灶相邻关节面可见裂隙,关节间隙无改变;(2)30例30个病灶CT表现为19个病灶呈圆形、3个呈半圆1形、8个呈不规则形,边缘骨质硬化,14个病灶相邻关节面可见裂隙,27个病灶密度均匀,3个病灶内可见气体;(3)14例共15个病灶MR T1WI表现为低到中等信号,T2WI为高信号,1例见液-液平面,8个病变近关节而骨质断裂,7例见软组织肿胀.结论 邻近关节的特殊发病部位结合典型影像表现,对邻关节囊肿能够作出正确的影像诊断.

Imaging diagnosis of the juxta-articular bone cyst

Objective To investigate the imaging features of the juxta-artieular bone cyst (intraosseous ganglia). Methods The imaging findings of 54 cases histopathologically confirmed were studied retrospectively. X-ray, CT, and MRI were performed in 46 eases,30 cases, and 14 cases, respectively.Results Of the 54 cases, 27 arised from the ankle (including multiple lesions), 16 from the knee joint,7 from the hip joint, 1 from the proximate end of the humerus, ulna, trapezium bone, the first phalange in each, and 1 from the talus and the distal end of the tibia. There were 43 eases (44 lesions) in the ankle and knee joints, with 29 (65.9%) lesions located in the medial articular surface. Fifty-four eases had thinning sclerotic rim, showing a unilocular round osteolytic appearance in 44 cases and a muhiloculated-cystic appearance with septa in 10 cases. Discontinuous articular surface were seen in 15 cases, articular surface collapse in 1, gas density in 3 and fluid-fluid plane in 1. (1) On x-ray films, 46 cases (47 lesions) with well-defined sclerotic rim revealed round, arch or irregular lyric areas at the adjacent articular surface. The fissures were found at the adjacent articular surface in 6 lesions. No joint spaces were abnormal. (2)On CT,30 cases with sclerotic rim showed round in 19 lesions, arch in 3, and irregular in 8. The fissures were seen at the adjacent articular surface in 14 lesions. The density showed homogeneous in 27 lesions, and gas existed in 3. (3) Fourteen cases (15 lesions)showed hypointense to isointense signal on MR T1 Wl and hyperintense signal on T2WI. Fluid- fluid plane was found in 1 ease. The fissures were observed at the adjacent articular surface in 8 lesions. 7 cases showed swelling soft tissue. Conclusion The characteristic locations combined with the typical imaging features may suggest the diagnosis of jaxta-articular bone cyst.