Shields Lisa B, Iyer Vasudeva G, Zhang Yi Ping, Shields Christopher B
Norton Neuroscience Institute, Norton Healthcare, Louisville, USA.
Clinical Neurophysiology, Neurodiagnostic Center of Louisville, Louisville, USA.
Cureus. 2023 Apr 26;15(4):e38162. doi: 10.7759/cureus.38162. eCollection 2023 Apr.
Isolated neuropathy of the dorsal cutaneous branch of the ulnar nerve (DCBUN) is rare and most cases are secondary to trauma, often iatrogenic. The topography of sensory abnormalities and abnormal electrodiagnostic (EDX) findings are crucial in confirming DCBUN neuropathy. Materials and methods: This is a retrospective study of patients with isolated involvement of the DCBUN from among patients referred for EDX studies for upper extremity symptoms. All patients underwent a focused neurological examination followed by EDX studies. Ultrasound (US) studies were performed in two patients. Results: Of the 14 patients with DCBUN neuropathy, decreased pinprick sensation in the distribution of the DCBUN was noted in 11 (78%) patients. DCBUN sensory nerve action potential (SNAP) was not recordable in 13 (92%) patients. In one patient who had a recordable SNAP, the latency was prolonged, and the amplitude was decreased. Four (28%) patients had incidental EDX abnormalities suggestive of entrapment of the median nerve at the carpal tunnel. The most common cause of DCBUN neuropathy was trauma in 13 (92%) patients, of which eight were iatrogenic. No specific etiology was detected in one patient (7%). Of the two patients who underwent US studies, one had increased cross-sectional area (CSA) at the wrist with prominent fascicles and hyperechoic scar tissue, while the CSA was normal in the other patient.
Although rare, DCBUN neuropathy can be readily confirmed by typical clinical features and EDX findings. Surgeons should be aware of the anatomy and clinical features of DCBUN neuropathy and avoid injuring the nerve during surgical procedures at the wrist and forearm.
尺神经手背支（DCBUN）孤立性神经病较为罕见，多数病例继发于创伤，常为医源性创伤。感觉异常的部位及异常的电诊断（EDX）结果对于确诊DCBUN神经病至关重要。
这是一项回顾性研究，研究对象为因上肢症状接受EDX检查的患者中DCBUN孤立受累的患者。所有患者均接受了针对性的神经系统检查，随后进行了EDX检查。两名患者进行了超声（US）检查。
在14例DCBUN神经病患者中，11例（78%）患者在DCBUN分布区域出现针刺觉减退。13例（92%）患者无法记录到DCBUN感觉神经动作电位（SNAP）。1例可记录到SNAP的患者，其潜伏期延长，波幅降低。4例（28%）患者伴有提示正中神经在腕管受压的EDX异常。DCBUN神经病最常见的病因是创伤，13例（92%）患者为此原因，其中8例为医源性创伤。1例患者（7%）未检测到具体病因。在接受US检查的两名患者中，1例患者腕部横截面积（CSA）增大，束状结构明显，有高回声瘢痕组织，而另1例患者CSA正常。
尽管DCBUN神经病罕见，但通过典型的临床特征和EDX结果可轻易确诊。外科医生应了解DCBUN神经病的解剖结构和临床特征，避免在腕部和前臂手术过程中损伤该神经。
