Nonaka Toshihiro, Sonohata Motoki, Takeshita Shuhei, Oba Yosuke, Fujii Yoshimasa, Mawatari Masaaki
Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan.
Open Orthop J. 2018 Aug 31;12:353-357. doi: 10.2174/1874325001812010353. eCollection 2018.
Intramuscular myxomas are rare, benign mesenchymal tumors in the musculoskeletal system, and usually, the tumors arise in the large muscles of the thigh, buttocks, shoulder, and upper arm. However, a tumor of the forearm is very rare. Herein, we describe the case of an intramuscular myxoma in the supinator muscle of a 56-year-old female patient.
Magnetic resonance imaging showed a well-defined mass that was hypointense with the peritumoral fat ring sign. The differential diagnoses might have been myxoma, schwannoma, or intramuscular hemangioma. The histopathological image showed abundant myxoid tissue, hypocellularity, and poor vascularization. The cells of the tumor were spindle and stellate-shaped with normochromic nuclei. Based on these findings, the pathological diagnosis was an intramuscular myxoma. After excising the tumor, the patient had transient posterior interosseous nerve palsy.
This tumor is curative by resection in toto; however, when the tumor exists in the forearm, surgeons should be careful to avoid damaging surrounding tissues because the tumor is very hard and relatively large compared to the forearm.
肌内黏液瘤是肌肉骨骼系统中罕见的良性间充质肿瘤，通常发生于大腿、臀部、肩部和上臂的大肌肉中。然而，发生在前臂的肿瘤极为罕见。在此，我们报告一例56岁女性患者旋后肌内肌内黏液瘤的病例。
磁共振成像显示一个边界清晰的肿块，伴有瘤周脂肪环征呈低信号。鉴别诊断可能为黏液瘤、神经鞘瘤或肌内血管瘤。组织病理学图像显示有丰富的黏液样组织、细胞稀少且血管化程度低。肿瘤细胞呈梭形和星状，核染色正常。基于这些发现，病理诊断为肌内黏液瘤。切除肿瘤后，患者出现了短暂的骨间后神经麻痹。
该肿瘤通过完整切除可治愈；然而，当肿瘤位于前臂时，由于肿瘤相对于前臂来说质地坚硬且体积较大，外科医生应小心避免损伤周围组织。
