Is it normal to crack your sternum?
Mostly.Normal for most people
An occasional painless pop around your sternum can happen, often from the joints where your ribs meet it. If it hurts, started after an injury, or comes with trouble breathing, get it checked—and don’t force it to crack.
Sometimes the sound people call a “sternum crack” comes from the small joints or cartilage where the ribs meet the breastbone. An occasional pop without pain is usually nothing to worry about, and plenty of people notice it when stretching or changing position.
Try not to force the crack, especially if it’s painful or happening more often. If you have ongoing pain, swelling, a recent injury, or trouble breathing, get medical advice rather than trying to pop it yourself.