Nowadays, there are especially many patients who go to the hospital and complain to the doctor about buttock pain, mainly the following diseases can be considered: a. Pear-shaped muscle syndrome The pear-shaped muscle starts in front of the 2nd, 3rd and 4th sacral vertebrae, is distributed on the inner surface of the small pelvis, enters the hip through the sciatic foramen and ends at the greater trochanter of the femur. This muscle is prone to injurious inflammatory changes due to acute or chronic injury, or anatomical variation, which can irritate or compress nerves and produce low back pain, called pear-shaped muscle syndrome, also known as femoral nerve pelvic outlet syndrome. Pear-shaped muscle injury is mostly caused by violent movements such as lower limb abduction, external rotation or internal rotation. The symptoms are very similar to disc herniation, but the patient has no lumbar pain and spinal signs, there is obvious localized pressure pain and radiating pain in the pear-shaped muscle, the pain is reduced after straight leg elevation 60°, and the local pain disappears; the pain disappears after pear-shaped muscle block. Patients complained of pain in the buttocks and lower limbs, mostly chronic, sometimes with acute attacks, aggravated by walking or activity, intermittent claudication may occur, alleviated by bed rest. The straight leg start height test may be positive, and may be accompanied by numbness in the lateral aspect of the calf and foot. Physical examination can be seen atrophy of the gluteus muscle, pressure pain in the area of the sciatic major incision, rectal palpation may touch the swollen and ancestral pear-shaped muscle, and can lead to the appearance of the above symptoms. ①Patients with pear-shaped muscle syndrome, no obvious pressure pain and deformity in the lumbar region, no restriction of movement; ②positive pear-shaped muscle tension test; pear-shaped muscle tension test is a method to check pear-shaped muscle injury. The specific steps are as follows: the patient lies on his back on the examination bed, straighten the affected limb, do internal rotation, if the sciatic nerve has radioactive pain, and then quickly abduct the affected limb and rotate it externally, the pain is then relieved, that is, the pear muscle tension test is positive. It is a common examination method for pear-shaped muscle syndrome; ③After the pressure point is closed locally with a long needle, the pain is immediately relieved. Primary sciatica: inflammatory lesion of the sciatic nerve or direct injury to the sciatic nerve (hip injection, surgery). The onset of the disease is acute, and the pain is along the pathway of the sciatic nerve from the buttock to the distal end via the posterior thigh and fossa to the lateral calf, and the pain is persistent and dull, and may increase episodically or be burning-like stabbing pain, and the pain is relieved when standing. Some people suddenly feel a sharp pain in one side of the buttock, and the leg and foot on the same side also tingle, and then the pain slowly disappears. Radicular sciatica is mostly caused by disc herniation, spinal osteoarthritis, spinal bone tumor and thickening of the ligamentum flavum and other intra-vertebral canal and spinal lesions. The onset of the disease is slow, with a history of chronic low back pain, pain is more pronounced in sitting position than walking, pain is relieved or disappears in lying position, symptoms can recur, skin sensation of the lateral calf and dorsum of the foot is reduced or disappears, flexor strength of the foot and toe dorsiflexion is reduced, ankle reflex is reduced or disappears, such lesions can be X-rayed to assist in diagnosis. There are deep and shallow abscesses in the buttocks. Generally, abscesses formed by subcutaneous soft tissues are called shallow abscesses, while abscesses located under deep fascia and in the muscle layer and formed in deep tissue spaces are called deep abscesses. The developed muscle of the buttocks is divided into blocks, the largest of which is the gluteus maximus, and if there is a purulent infection in that muscle or between the muscles, a deep abscess will be formed. V. Sciatic nerve sheath tumor Nerve sheath tumor occurs in the sensory, motor or mixed peripheral nerve sheath cells, mostly in the neck and extremity nerves, the size is usually about 3cm, a few have more than 10cm, the sciatic nerve sheath tumor buttock bulge, find a huge mass deeper, surgery is the only treatment for this disease. The cause of epiglottic neuritis, also called “posterior branch of lumbar spinal nerve pain”, is multifaceted, such as small intervertebral joint lesions, osteophytes, posterior branch of spinal nerve compression, chronic aseptic inflammation of the posterior branch. Because the superior gluteal cutaneous nerve comes from the lateral cutaneous branch of the posterior branch of the spinal nerve from lumbar 1 to lumbar 3 and is distributed in the lateral skin of the upper gluteal area, pain often appears in the lumbar, hip and thigh areas and rarely exceeds the knee joint. A comprehensive judgment is made based on history, symptoms and signs. There is pressure pain and soft tissue stripe-like hardness at 3-5 cm below the highest part of the iliac crest. Non-specific inflammation characterized by osteosclerosis, with highly dense osteosclerosis, especially in the lower 2/3 of the iliac crest, but no change in the joint space. There is recurrent lower back pain, sometimes radiating down to the buttocks and thighs on both sides. Pseudosciatica The gluteus minimus muscle in the buttocks swells after frostbite and compresses the sciatic nerve, causing pain. The buttock pain caused by pseudosciatica is not painful in the lower back but most painful in the buttocks, and there is pressure pain.