We describe an unusual case of infant obstetric brachial plexus injury located in the cervical (C)5–C6 brachial plexus nerve, which was preoperatively diagnosed using high-frequency ultrasonography (US) at 2 years of age. The girl was diagnosed with a right clavicular fracture because of shoulder dystocia. She had been showing movement limitations of her entire right upper limb after fracture healing and was then referred to our hospital at 2 years of age. High-frequency US showed that the roots of the right brachial plexus ran continuously, but the diameter of C6 was thinner on the affected side than on the contralateral side (right 0.12 cm vs. left 0.20 cm). A traumatic neuroma had formed at the upper trunk, which was thicker (diameter: right 0.35 cm vs. left 0.23 cm; cross-sectional area: right 0.65 cm² vs. left 0.31 cm²) at the level of the supraclavicular fossa. Intraoperative findings were consistent with ultrasound findings. Postoperative pathology confirmed brachial plexus traumatic neuroma.

Graphical Abstract

中文翻译：

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高频超声诊断2岁女童产科臂丛神经损伤

我们描述了一个罕见的婴儿产科臂丛神经损伤病例，该损伤位于颈 (C)5-C6 臂丛神经，该损伤是在 2 岁时使用高频超声检查 (US) 术前诊断的。女孩因肩难产被诊断为右锁骨骨折。骨折愈合后，她的整个右上肢出现运动受限，2岁时被转诊至我们医院。高频超声显示右侧臂丛根部连续走行，但患侧C6直径较对侧细（右侧0.12 cm，左侧0.20 cm）。上躯干形成创伤性神经瘤，锁骨上窝水平较厚（直径：右侧 0.35 cm 比左侧 0.23 cm；横截面积：右侧 0.65 cm ²比左侧 0.31 cm ²）。术中检查结果与超声检查结果一致。术后病理证实为臂丛神经创伤性神经瘤。

图形概要