The diagnosis of brachial plexus injury should be clarified as soon as possible after the patient has recovered from the risk of injury elsewhere. The diagnosis should usually be made within three months and is based on: history, clinical examination: X-ray: Li Jun, Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University: Intradural epidurography: It is mainly used to determine whether or not a radicular avulsion of the nerve has occurred. Electromyography: (Electromyogram (EMG or electromyography)) to check the conduction velocity of the nerve trunk conducting nerve electricity to the muscle, at rest and during contraction. MRI: