In the outpatient clinic some patients feel that they have no strength in their arms or limbs and think that it is muscle weakness, what causes this condition? In fact, there are many kinds of factors to be analyzed, including both orthopedic factors and factors of some other departments, such as nerve damage to the limb, whether it is spinal cord or peripheral, may cause the muscles to appear to have no strength, such as common cervical spondylosis or lumbar intervertebral disc herniation, because of the spinal cord nerve compression and led to the distal hand or foot of the limb, such as weakness in clenching the fist or no strength in hooking the toes, which is caused by the nerve This is caused by nerve damage. Others are due to lack of muscle strength, such as lower limb ankle fracture, which requires cast braking, and after 3-4 weeks of casting, the cast is removed, and the muscles may atrophy due to long-term braking, and there may be no strength in hooking the toes. There are also specific diseases, including those in other departments, such as electrolyte disorders, such as hypokalemia, that may cause weakness of the limbs. Thus, there are a very wide range of causes of limb weakness, from orthopedic conditions to other conditions, from localized problems to possible systemic problems. Only by combining each person’s medical history, clinical physical examination, and many auxiliary tests, and making a comprehensive analysis and judgment, and even inviting a lot of departments to sit down together for consultation and diagnosis, can we clarify what exactly is the cause of muscle weakness.