Hi, at birth my son's sternum was visibly lying horizontal but not protruding. This did not affect his growth or excersise abilities. At about 10 years old he had his first palpitation. It wasn't until these palpitations became more regular that we took him to a pediatrician (nothing was ever mentioned by any doctor about his sternum - although visibly different it hadn't grown but remained small & flat) My son grew up knowing this was his 'special bone', his wish-bone. At about 11 years old his sternum grew at an alarming rate (about 2cm protruding) but seemed to plateau at 14. It is off centre with one side of his rib-cage slightly larger than the other. Because of our fear of the unknown we hindered his sports - to his deterament in his early teen years, he did not develop as well as the average teenage boy although he outgrew his palpitations. We realise now that palpitations are related to a protruding sternum.
We found swimming an excellent form of chest-muscle development - aiding a mask for the protruding sternum. Any form of excercise is brilliant for this 'special bone' as they don't 'go away'.
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