Pisapia Jared M, Ali Zarina S, Hudgins Eric D, Khoury Viviane, Heuer Gregory G, Zager Eric L
Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
World Neurosurg. 2017 Mar;99:809.e1-809.e5. doi: 10.1016/j.wneu.2017.01.007. Epub 2017 Jan 12.
Dislocation of the ulnar nerve (UN) occurs in a subset of patients with ulnar neuropathy. Electrodiagnostic and magnetic resonance imaging (MRI) studies are performed to support the clinical diagnosis. We report the case of a patient with ulnar neuropathy with normal electrodiagnostic and MRI studies but with ultrasonography (US) showing UN dislocation, which prompted successful treatment by UN submuscular transposition.
A healthy 15-year-old female softball player presented with right medial elbow pain and paresthesias of the fourth and fifth digits. She had 4+/5 strength in the right hand intrinsic muscles and a Tinel sign at the right elbow. A snap was palpated at the elbow upon flexion. MRI showed mild common flexor tendonitis, and electrodiagnostic studies showed normal motor responses and no conduction block at the elbow. High-resolution US showed dislocation of the UN over the medial epicondyle. UN dislocation was confirmed intraoperatively, and, after UN submuscular transposition, the patient reported complete resolution of her preoperative symptoms at 6-week follow-up and continued resolution at 1 year.
Normal findings on electrodiagnostic or MRI studies should not immediately dissuade surgeons from operating on a symptomatic patient with a clinical examination supporting ulnar neuropathy and with US evidence of UN dislocation, because such a patient may experience postoperative symptom relief. Furthermore, the dynamic capability of US imaging complements data obtained from electrodiagnostic and MRI studies, especially when these tests are normal, and it should be considered by clinicians when evaluating patients with medial elbow pain or signs of ulnar neuropathy.
尺神经（UN）脱位发生在一部分尺神经病变患者中。进行电诊断和磁共振成像（MRI）研究以支持临床诊断。我们报告了一例尺神经病变患者，其电诊断和MRI研究结果正常，但超声检查（US）显示尺神经脱位，这促使通过尺神经肌下转位成功治疗。
一名健康的15岁女性垒球运动员出现右内侧肘部疼痛及第四和第五指感觉异常。她右手固有肌肌力为4+/5，右肘部有Tinel征。屈曲肘部时可触及弹响。MRI显示轻度肱二头肌肌腱炎，电诊断研究显示运动反应正常，肘部无传导阻滞。高分辨率超声显示尺神经在内侧髁上脱位。术中证实尺神经脱位，尺神经肌下转位后，患者在6周随访时报告术前症状完全缓解，1年时持续缓解。
电诊断或MRI研究结果正常不应立即阻止外科医生对有临床检查支持尺神经病变且有超声证据显示尺神经脱位的有症状患者进行手术，因为此类患者术后症状可能会缓解。此外，超声成像的动态能力补充了从电诊断和MRI研究中获得的数据，尤其是当这些检查结果正常时，临床医生在评估有内侧肘部疼痛或尺神经病变体征的患者时应考虑这一点。
