Pain under the left shoulder blade is observed in musculoskeletal pathology (osteochondrosis, myofascial syndrome, injuries), heart diseases (myocardial infarction, angina pectoris, rheumatic and non-rheumatic carditis), gastrointestinal diseases (pancreatitis, stomach ulcer). Rare causes of a symptom include damage to the spleen, abscesses, and skin neoplasms. Diagnostic methods are selected based on the underlying syndrome: X-ray, ultrasound and endoscopic studies are used. To relieve pain, analgesics are prescribed, after which medical or surgical treatment of the underlying disease is carried out.