患者女 ,46岁。进行性双下肢无力 2年 ,2年前无明显诱因出现左下肢发作性肌痉挛 ,后渐发展为双侧肢体 ,并觉双下肢无力 ,由远端向近端发展。神经科检查 :神志清 ,言语流利 ,脑神经检查无异常。双上肢肌力、肌张力、腱反射均正常 ,霍夫曼组 (- )。双下肢肌张力、肌容积正常 ,肌 Female patient, 46 years old. Progressive lower extremity weakness 2 years, 2 years ago, there was no obvious incentive for left lower extremity episodes of muscle spasm, and later developed into bilateral limbs, and feel both lower limb weakness, from distal to proximal development. Neurological examination: Consciousness, fluent speech, no abnormalities in brain examination. Double upper limb muscle strength, muscle tone, tendon reflexes were normal, Huffman group (-). Lower extremity muscle tone, muscle volume normal, muscle