In clinical practice, the first step in treating a disease is to identify the cause. Can you correctly identify the cause for patients with medial scapular rim pain? Anterior trapezius strain has an 80% chance of radiating to the upper 2/3 of the medial scapular margin. The main symptoms are upward conduction to the upper half of the scapular spine margin and interscapular area; downward conduction around the anterior and posterior sides of the upper arm to the elbow joint to the radial side of the forearm, up to the pain of the thumb and index finger. Scapular raphe strain 30% probability of radiating to the upper 1/4 of the medial scapular margin, with the main presenting symptom being pain 1-2 cm above the upper edge of the medial superior scapular angle, limiting rotation to the opposite side, and often accompanied by first rib dysfunction, limiting ipsilateral rotation and causing stiffness in the neck. The latissimus dorsi strain has a 30% probability of radiating to the inferior scapular angle with the lower 1/3 of the medial border, with a painful area the size of a fist. The main presenting symptoms are pain in the triceps, ring finger and little finger. Subacromial strain has a 20% probability of radiating to the middle 1/2 of the medial border of the scapula, with the main symptoms being deep anterior shoulder pain and pain in the lower anterior biceps of the upper arm causing inability to touch the back back. The anterior serratus muscle has a 20% probability of radiating to the lower 1/3 of the subscapularis and the medial border of the scapula, with a painful area about the size of two thumbs, mainly manifesting as pain occurring in the anterolateral aspect of the middle level of the chest and resembling a sensation of breathlessness due to thin air. The thoracic multifidus muscle has a 10% probability of radiating to the middle 1/2 of the medial border of the scapula and involving the spine, with most of the pain involving the spine. The thoracic-iliac rib muscle has a 10% probability of radiating to the lower medial border of the scapula and decreasing in pain proximally to the spine, with the main symptom being pain along the lower medial border of the scapula and decreasing in pain proximally to the spine. The inferior trapezius muscle has a 10% probability of radiating to the lower 4/5 of the medial scapular border, with a narrower range of pain. The main symptom is a mild burning pain that is not severe. The rhomboid muscle has a 5% probability of radiating to the scapula and the middle 1/2 of the medial border of the paraspinal column. The patient complains of superficial muscle soreness at rest, but it does not interfere with daily life. The superior posterior serratus has a 5% probability of radiating to the upper 1/2 of the medial border of the scapula, with deep scapular pain. The patient feels deep pain in the little finger and cannot be touched.