No strength in the arms, the following common causes: First, excessive strain on the upper limbs: If patients participate in long-term heavy physical labor or short-term strenuous exercise, can lead to arm weakness symptoms, muscle strain, but also accompanied by muscle pain and other clinical symptoms, through massage, hot compresses, rest, etc., can make the symptoms get rapid relief. Second, cervical spine disease: severe cervical disc herniation, cervical spinal stenosis will compress the nerve roots, resulting in the disappearance of the innervation of the upper limbs, muscle atrophy will be obvious, the strength will be significantly weakened, the patient will also be accompanied by neck pain and cervical spine activity limitation, through the cervical spine nuclear magnetic examination will find the specific location and severity of the lesion. The lack of strength in the arm should be diagnosed and treated early, which will lead to rapid relief of clinical symptoms. If the diagnosis is delayed, it can cause degeneration and necrosis of the nerves, resulting in failure to restore muscle strength in the upper limbs.