When the body performs a movement, the muscles and the brain send messages to each other, forming a neural feedback loop that will be reactivated the next time this movement occurs. Sometimes, this loop can be interrupted or malformed through injury or bad habits, resulting in injury or muscular atrophy. Lately, I've also been wondering whether some of these feedback loops are actually sub-optimally formed during early development.
For instance, it seems that babies learn movement patterns through trial and error and in a relatively specific order (eg: certain muscular patterns must be activated in order to crawl, walk etc.). The baby throws its arm out to the side and the brain says oh, that's my arm, and it can do that, wow! Gradually muscular patterns are developed that allow the baby to perform complex movement tasks. However, it seems to me that these patterns can be interrupted as it were, by accidents, injury and genetic predispositions, and as a consequence, a baby can form various 'work arounds'. The result is a series of sub-optimal movement patterns that are then in place for life. I wonder whether some injuries later in life are the result of these flawed patterns, and whether the patterns then need to be reset in order to encourage healing. Anyway, certainly food for thought.