dear freind, welcome to HCM.
the history trauma and cracking on even deep breathing would prompt me to rule out rib fractures
is there any pian in the chest/ back or breathlessness?
get an Xray done to rule out rib fractures. they may sometimes cause pneumothorax
, which can be risky.
also if you have any pain in the spine/ tingling/ numbness
below, get the spine evaluated as well.
take care and keep me posted on your progress.
Good luck !