Pain is recognized by the World Health Organization as the fifth most important vital sign (temperature, pulse, respiration, blood pressure, pain). Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. In adults, the prevalence of pain is approximately 40%, and nearly 70% of these pain patients never visit a specialized pain clinic. The low visibility of pain clinics among patients is also one of the reasons for the low attendance rate. Due to their economic status, some patients believe that only diseases with high mortality such as cardiovascular and cerebrovascular diseases need to be treated in hospitals. So what diseases are seen in the pain department? Mainly, the pain department can be divided into several categories: 1. neuropathic pain: trigeminal neuralgia, postherpetic neuralgia, phantom limb pain after amputation, peripheral neuropathic pain, reflex sympathetic dystrophy and sympathetic persistent pain, and atypical facial pain, nerve root injury and arachnoiditis; 2. pain caused by various cervical spondylosis, lumbar disc herniation, lumbar spondylolisthesis, etc.; 3. soft tissue 3, soft tissue, joint and bone pain: various osteoarthritis, post-traumatic deformity pain, skeletal muscle pain, lumbago, myofascial pain syndrome, headache, post-burn pain, post-surgical incision pain syndrome, etc.; 4, central pain: vascular injury of the brain and spinal cord, such as hemorrhage, infarction, vascular malformation; multiple sclerosis, traumatic spinal cord injury and brain injury, spinal cord cavitation and medullary cavitation, tumors, Parkinson’s disease 5, severe bone pain caused by osteoporosis; 6, deep tissue and visceral pain: cardiovascular pain, eye pain, orofacial pain, chronic gynecological pain, painful sexual intercourse, chronic pain of the genitourinary system; 7, cancer pain, bone pain caused by tumor bone metastases; 8, non-painful diseases: intractable eruption (hiccups), facial neuritis (facial palsy), facial muscle spasm sleep disorder, dysmenorrhea, Raynaud’s syndrome caused by peripheral vascular occlusion, restless leg syndrome, etc.