Sukockienė Eglė, Assal Frédéric, Hübers Annemarie
Department of Clinical Neurosciences, Geneva University Hospitals, Switzerland.
Clin Neurophysiol Pract. 2022 Jun 2;7:166-168. doi: 10.1016/j.cnp.2022.05.003. eCollection 2022.
Functional neurological disorders represent conditions without a readily identifiable origin or laboratory-supported diagnostic. We report a case of functional neurological disorder, presenting with muscle weakness with alterations in F-waves on the affected side.
A retrospective case review of a patient seen in clinic. Electrophysiological evaluation included nerve conduction studies, including recording of F-waves in lower limbs, and needle EMG. A patchy sensory loss and unilateral muscle weakness of the left lower limb persisted nine days after a 40-year-old female patient developed bilateral lower limb weakness following a laparoscopic surgery. MRI was negative for radicular compression, myelopathy, or lumbosacral plexopathy. F-waves of the peroneal and tibial nerves on the left were absent or of reduced persistence and amplitude compared to the asymptomatic right side.
The observation of unilateral alterations of F-wave parameters could be interpreted as an asymmetrical decrease of alpha motor neuron excitability on L4 - S2 segments. In the absence of peripheral nervous system dysfunction or a structural lesion, the results here suggest a central control dysfunction or point to a more complex peripheral role. Further research is necessary to determine the frequency of these findings in a larger group of patients while incorporating other late responses, such as H (Hoffman) reflex, and measures of cortical excitability.
功能性神经障碍是指那些没有易于识别的病因或实验室支持诊断的病症。我们报告一例功能性神经障碍病例，其表现为患侧肌肉无力伴F波改变。
对一名门诊患者进行回顾性病例分析。电生理评估包括神经传导研究，包括记录下肢的F波，以及针极肌电图检查。一名40岁女性患者在腹腔镜手术后出现双侧下肢无力，9天后左下肢仍存在斑片状感觉丧失和单侧肌肉无力。磁共振成像（MRI）显示神经根受压、脊髓病或腰骶丛病变均为阴性。与无症状的右侧相比，左侧腓总神经和胫神经的F波缺失或时限及波幅降低。
F波参数单侧改变的观察结果可解释为L4 - S2节段α运动神经元兴奋性的不对称降低。在没有外周神经系统功能障碍或结构性病变的情况下，此处结果提示中枢控制功能障碍或表明外周存在更复杂的作用。有必要进行进一步研究，以确定在更大规模患者群体中这些发现的频率，同时纳入其他晚期反应，如H（霍夫曼）反射，以及皮质兴奋性测量。
