Costochondritis is a non-suppurative inflammatory lesion of the rib cartilage at the junction of the rib cartilage and sternum of unknown origin. It presents as a self-limiting disease with limited pain and swelling, and is more common in patients aged 20-30 and 40-50 years. The incidence is similar on the right and left sides. 70%-80% of the lesions are unilateral and solitary. There is no significant gender predilection. The etiology is unknown and may be related to microtrauma of the costal cartilage membrane and strain caused by abnormal local stresses in the ligaments of the sternocostal joints, to viral infections of the upper respiratory tract, or to immune or endocrine abnormalities causing nutritional disorders of the costal cartilage. Clinical manifestations and diagnosis The disease can develop in all rib cartilages, mostly in the parasternal 2-4 ribs, but also in the rib arch. In mild cases, only mild chest tightness is felt, and the pain in front of the chest is mostly dull or hidden pain, occasionally accompanied by stabbing pain, and the pain point is fixed and does not move, and the pain increases when the thorax is overactive due to coughing, deep breathing, expanding the chest wall, etc. In severe cases, the pain is fearful in the shoulder and arm, and may even involve the half of the body. The course of the disease mostly heals on its own in 3-4 weeks, but some patients have recurrent episodes that extend for months or even years. The affected costal cartilage is enlarged and elevated, hard, smooth and poorly defined, with significant localized pressure pain without epidermal redness or heat, and the pain increases when the thorax is squeezed. In multiple cases, the involved costal cartilage may show a bead-like deformity. CT is good at showing cartilage swelling and ossification, but not active inflammation under the periosteum, MRI is good at showing active inflammatory changes in bone, cartilage, synovium and bone marrow with high specificity and sensitivity. Ultrasound can show swelling and structural alterations of rib cartilage, avoiding false positives or false negatives of CT due to volumetric effects and body position, and it is easy to observe swelling changes by bilateral comparison. The diagnosis of costochondritis is confirmed on the basis of clinical manifestations and signs after detailed history, careful physical examination and ancillary tests to exclude other diseases. What are the treatment methods? 1, the use of non-steroidal analgesic and anti-inflammatory drugs symptomatic treatment; 2, if the pain is obvious, symptomatic treatment is not good, can be aseptic operation in the swollen cartilage periosteum injection mixed with procaine or lidocaine long-acting steroid hormone local closed treatment, to reduce swelling and pain effectiveness; 3, other treatment: physical therapy, hot compresses, antibiotics, etc., but the effect is not good. The purpose of physical therapy is to reduce inflammation and swelling, reduce nerve endings stimulation and analgesia, and promote blood circulation to improve local nutrition; 4, for a small number of non-surgical treatment is ineffective, the rib cartilage enlargement and symptoms are obvious and serious, recurrent, heavy psychological burden, do not exclude malignant lesions, should be removed from the diseased rib cartilage to achieve a cure.