Superficial pain ard central & right of sternum after work. feels spasm. intensify after lifting/shl ext rotate/deep breath. why?

Costochondritis: Costochondritis is an acute and often temporary inflammation of the costal cartilage, the structure which connects each rib to the sternum at the costosternal joint. Pain or tenderness to palpation usually occurs on the sides of the sternum, affects multiple ribs, and is often worsened with coughing, deep breathing, or physical activity. In most cases no cause is identified. Treatment: ibuprofen