What are the common types of headaches seen in the pain clinic? Headaches are the most common type of pain, and almost everyone has a history of headaches during their lifetime. A headache may be a transient symptom or a concomitant symptom of another disorder, but it may also be a separate disorder. There are many different types of headache disorders, and the most common types of headaches in pain clinics are: cervicogenic headache, migraine, tension-type headache, cluster headache, etc. However, there are great difficulties in treatment because their etiology and pathogenesis are complex or even unclear. What are the pathogenesis of cervicogenic headache? Cervicogenic headache can be divided into neurogenic pain and myogenic pain according to the different sites of nerve involvement. Stimulation of sensory root fibers of nerve roots causes neurogenic pain, while stimulation of its ventral motor nerve roots is myogenic pain. (1) Relationship between anatomical basis and cervicogenic headache The fibers of the 2nd cervical nerve and the 3rd cervical nerve together form the greater occipital nerve, the lesser occipital nerve and the greater auricular nerve, which are the main nerves conducting cervicogenic headache. The branches of these nerves are close to the angle of the vertebral artery before it enters the cranial cavity through the foramen magnum, and are susceptible to irritation and injury from the vertebral prominence and muscle attachments. Inflammation, ischemia, injury, compression and even inappropriate massage of soft tissues can affect the function of the nerves and trigger cervicogenic headache. (2) Cervical spine and intervertebral disc degeneration causes intervertebral foramen stenosis. After degeneration or protrusion of cervical intervertebral disc, it becomes “hard” through “fibrosis”, and later, with tissue repair and calcification, it can form osteophytes, which deform the intervertebral foramen, and the space of intervertebral foramen is encroached upon, thus This can cause pain and neurological dysfunction by provoking the nerves that pass through it. (3) Non-bacterial inflammation caused by cervical disc degeneration and herniation Cervical disc degeneration and herniation, and release of disc material can directly cause non-bacterial inflammation and edema. The human immune system views the disc material as a foreign body and produces immune rejection reactive inflammation, causing cervical discogenic radiculitis. In addition to the direct production of radicular pain, pain can also be produced by the release of inflammatory mediators at the end, causing soft tissue inflammation within the distribution area. This is the mechanism by which intractable cervicogenic headache occurs in some patients. (4) Muscle spasm Cervicogenic headache can also be produced in the muscle tissue of the neck. On the one hand, when the nerve governing the movement is compressed or inflamed, it can cause reflex cervical muscle spasm; on the other hand, persistent chronic muscle spasm causes tissue ischemia, and metabolites gather in the muscle tissue, causing myofasciitis and pain, and can directly stimulate the nerve trunks and nerve endings traveling in the soft tissue to produce pain. The pain can be produced by direct stimulation of the nerve trunks and nerve endings that travel through the soft tissue. Long hours of work with head down, muscles need to contract continuously to maintain posture, which reduces muscle blood supply and causes muscle spasm, and makes ligaments and myofascia prone to injury; long and tedious mental activities or physical labor are the most likely to cause tension in the nerves and muscles of the neck among all parts of the body. What are the clinical manifestations of cervicogenic headache? Patients with cervicogenic headache are mostly aged 20-60 years old, and are more common in women. In the early stage, it is mostly discomfort in the occipital area, behind the ear, or under the ear, which later turns into a dull or sore feeling and gradually becomes painful. The painful area may extend to the forehead, temporal region, top, and neck. In some cases, pain in the upper extremity of the ipsilateral shoulder and back may occur at the same time. The pain may be aggravated by cold, exertion, alcohol consumption, and emotional excitement. Some patients have tinnitus, ear swelling, eye stuffiness, and stiffness in the neck. Most patients prefer to press the painful area with their hands for relief during painful episodes. Oral non-steroidal anti-inflammatory drugs (e.g., fen-phen) can reduce the headache. The incidence of cervicogenic headache is higher among desk-bound workers. The quality of life and work is significantly reduced due to decreased work efficiency, reduced concentration and memory, depression, irritability, and irritability. The cervical intervertebral foramen is narrowed, the anterior and posterior edges of the vertebral body are enlarged, or the spinous process is widened and thickened, and the supraspinous ligament is calcified.