Sternum Pain If I Twist Sideways It Cracks Or Pops
Costochondritis is possible.
Detailed Answer:
Hello dear, welcome to Ask a doctor service. I read your query and here is my advice.
According to your symptoms of pain acompained by popping sounds in chest I think it doesn't have to do with heart or lungs but most probably with bones, cartilages and articulacions.
I think your situation may be caused by costochondritis, inflammation of the cartilage of the rib cage.
Certain conditions such trauma, muscle strain, arthritis may cause it.
Some physical activities such weightlifting, running or manual labour may make it worse so you can avoid these activities.
Taking antinflammatory drugs such advil or naproxen can help with pain and inflammation.
Hope I have answered the question.
Let me know if I can assist you further.