Charcot关节的影像表现

目的 探讨Charcot关节的MRI表现，评价X线片、CT及MRI对Charcot关节的诊断价值。方法 对8例Charcot关节作X线、CT及MR检查，其中6例患有脊髓空洞症，1例为胸髓损伤截瘫患者，1例为糖尿病患者，所有8例均有患肢的痛觉减退或消失。结果 (1)Charcot关节表现为增生和吸收2型。(2)X线及CT特点：3例增生型关节骨质增生硬化、骨赘形成，关节周围软组织肿胀，内见大量块状骨化影；5例吸收型关节以骨质破坏吸收、碎裂为主，骨端消失，其中3例残端平齐如手术切除，周围软组织肿胀，内见多个小而锐利的骨化影。8例中有3例伴有关节半脱位。(3)主要MRI特点：8例均清楚显示关节周围软组织块影结构，7例分为3层：由内向外为关节囊内积液、关节囊壁及囊壁外其余软组织块影，1例关节囊壁与其外软组织块影分界不清，表现为2层结构。关节囊壁不均匀增厚、松弛及拉长，在关节周围、骨干旁或肌间隙内呈伪足状伸延，T1WI呈稍低信号，T2WI呈稍高信号，注射钆喷替酸葡甲胺(Gd—DTPA)后明显强化，其强化程度常高于外周的软组织块影。关节周围软组织块影的3层结构及关节囊的改变较具特点。结论 X线片是Charcot关节的首选诊断手段，MRI在Charcot关节的诊断及鉴别诊断方面是X线片重要的补充手段。

Imaging findings of Charcot joint

Objective To analyze the MRI characters of Charcot joint, and to evaluate the diagnostic value of X-ray, CT, and MRI on Charcot joint. Methods Eight patients with 8 Charcot joints underwent X-ray, CT, and MR examinations. 6 of them had syringomyelia, 1 patient had injury of the spinal cord, and 1 case had diabetes. All 8 patients had sensory reduction or deficit in the sick extremities. Results There were two types of Charcot joint, hypertrophic and atrophic. Radiographic and CT features of hypertrophic joint (n=3) showed hyperostotic osteosclerosis and mammoth osteophytes in the sick bones, periarticular ossification,and articular disorganization. Radiographic and CT features of atrophic joint (n=5) showed extensive bone resorption (destruction), periarticular debris, and articular disorganization. Main MRI features of Charcot joint included hydrarthrosis within joint capsule, thickened, loose, and elongated joint capsule with para-joint, peri-diaphysis, and inter-muscular extension in a pseudopodia pattern. The irregular joint capsule wall was presented as mild hypointensity on T 1WI, slight hyper-intensity on T 2WI, and was markedly enhanced after Gd-DTPA was administrated, which was considered as a characteristic manifestation of the lesion. Soft tissue mass containing hypo-intense stripes on both T 1WI and T 2WI was commonly noted adjacent to the involved joint. Conclusion X-rays plain film is the first choice for the diagnosis of Charcot joint, and MRI is pretty useful in the diagnosis of Charcot joint.