Pain in the left back under the shoulder blade is mainly seen in the following clinical conditions: First, coronary artery disease coronary blood supply insufficiency, this patient may have hypertension, diabetes, hyperlipidemia and other risk factors, symptoms appear in the case of activity, can be relieved after rest, check the electrocardiogram and cardiac ultrasound can help to clarify the diagnosis. Second, aortic coarctation, this patient often has a history of hypertension, and usually blood pressure control is not good, sudden exertion of back tear-like pain, accompanied by abnormally high blood pressure, this case should be alert to the aortic coarctation, and improve the aortic CTA in a timely manner to make a definitive diagnosis. Third, cervical spondylosis, can also appear this kind of pain below the shoulder blade, but patients often have long-term bad habits, such as low head, sedentary, etc., in addition to pain, the patient may also be accompanied by dizziness, numbness of the limbs and other sensations, checking the cervical spine CT can help to clarify the diagnosis.