Supplementary Material for: Expanding the Differential Diagnosis of the Painful Nail: A Case of an Onychopapilloma with Neuroma

Introduction: Onychopapilloma most commonly presents as longitudinal erythronychia, but diagnosis may be challenging in some cases due to varied clinical presentations. Most patients with onychopapillomas do not report associated pain, but instead more commonly report functional interference. Case Report: We present a case of a 74-year-old female with a 5-year history of splitting and lifting of the right thumbnail, accompanied by nail sensitivity and intermittent painful throbbing. Clinical examination was significant for a less than 1 mm red line with distal onycholysis. Love’s test and a cold test performed with ice-pack were negative. X-ray of the right thumb was negative for erosion or exostosis. Nail biopsy was performed and dermatopathology was consistent with onychopapilloma with a concomitant traumatic neuroma. Conclusion: We report a case of onychopapilloma with a concomitant traumatic neuroma. Subungual neuromas are extremely rare, and have not previously been associated with onychopapilloma. Our case supports the expansion of the differential diagnosis for a painful nail and demonstrates the importance of diagnostic confirmation with biopsy and histopathology.引言：甲乳头瘤（Onychopapilloma）最常见的表现为纵向红甲症（longitudinal erythronychia），但由于临床表现多样，部分病例的诊断颇具挑战。多数甲乳头瘤患者无伴随疼痛症状，更多表现为甲功能受累。 病例报告：本例为一名74岁女性，右拇指甲分裂、翘起症状持续5年，伴甲部敏感及间歇性搏动痛。临床检查可见一条长度不足1mm的红色线条，伴远端甲分离。洛夫试验（Love’s test）及冰袋冷试验结果均为阴性。右拇指X线检查未发现骨质糜烂或外生骨疣。遂行甲活检术，皮肤病理结果符合甲乳头瘤合并创伤性神经瘤。 结论：本例报告1例甲乳头瘤合并创伤性神经瘤的病例。甲下神经瘤极为罕见，此前未见与甲乳头瘤相关的关联报道。本病例支持扩大疼痛性甲病变的鉴别诊断范围，并凸显了活检及组织病理学确诊的重要性。