I have the same problem. I feel the need to pop mine after doing things that involve having my arms out in front of my body, like mowing the lawn or edging. I mentioned this to a chiropractor once and he said it is nothing to worry about. It is the manubrium and body of the sternum getting separated and popping back into place. I have never asked an MD about it however. I have had chest x-rays done in the past for broken ribs and no one ever mentioned any abnormalities with my sternum. If gets to be painful then see a doctor.

It is simply popping a joint. Me and my friends (college age guys) have talked about it and we agree it is the coolest feeling "pop" you can do with your body. But it is the same mechanism as popping your knuckles, it is just harder to do that with the sternum because the joint between the ribs and the sternum is not as mobile as your knuckles or toes. Though if you look at a picture of a sternum it appears to almost be in two pieces, so possibly it is between this "joint" that the gases form bubbles and pop. Either way its not dangerous and you shouldn't worry about.

I pretty much agree...while I don't feel any tightness or pain, when I'm trying to pop my back, sometimes my chest pops too. It would make sense that hunched over a keyboard could lead to this, as the small joints of your ribs-sternum would be kept in the same position for a while...

Your ribs join into your chest similar to every other joint in your body, though still somewhat uniquely. If there's no inflammation or additional discomfort as mentioned in the condition above, it's likely harmless (as you've decided for yourself, it seems).

I don't get the corresponding tightness, but occasionally, I will stretch in the 'right' way and get a pop similar to what you experience.

As with any anomalous body behavior: If you're concerned at all, it never hurts to get it checked out.

Sounds like it could be Costochondritis.

"Costochondritis is an inflammation of the junctions where the upper ribs join with the cartilage that holds them to the breastbone or sternum. The condition causes localized chest pain that you can reproduce by pushing on the cartilage in the front of your ribcage. Costochondritis is a relatively harmless condition and usually goes away without treatment. The cause is usually unknown.

* Costochondritis (with unknown cause) is a common cause of chest pain in children and adolescents. It accounts for 10-30% of all chest pain in children. Annually, doctors evaluate about 650,000 cases of chest pain in young people 10-21 years of age. The peak age for the condition is 12-14 years.

* Costochondritis is also considered as a possible diagnosis for adults who have chest pain. Chest pain in adults is considered a potentially serious sign of a heart problem by most doctors until proven otherwise. Chest pain in adults usually leads to a battery of tests to rule out heart disease. If those tests are normal and your physical exam is consistent with costochondritis, your doctor will diagnose costochondritis as the cause of your chest pain. It is important, however, for adults with chest pain to be examined and tested for heart disease before being diagnosed with costochondritis. Often it is difficult to distinguish between the two without further testing. The condition affects females more than males (70% versus 30%). Costochondritis may also occur as the result of an infection or as a complication of surgery on your sternum.

* Tietze syndrome is often referred to as costochondritis, but the two are distinct conditions. You can tell the difference by noting the following:

o Tietze syndrome usually comes on abruptly, with chest pain radiating to your arms or shoulder and lasting several weeks. Tietze syndrome is accompanied by a localized swelling at the painful area (the junction of the ribs and breastbone)."

As a former personal trainer, my only recommendation is to start doing some minor exercise. It can strengthen the structure around the area, which might be why it's cracking.

The thing to remember is, stuff like that can get worse if it's actually something bad. I don't know if you exercise. But even light and extremely infrequent exercise is always important. A few pushups here and there, maybe a pull up on a doorway, can go a long way if you never ever ever exercise.

Do you do pushups ever?

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