western boxing is simply western boxing.
"through the back" is an older conceptualization of the posterior chain and anterior chain.
Born in ancient time and changed and developed with rules etc etc over time up until we have what it is now.
What we have now is pretty much 100 years old or so.
It merely has a rule set and you can be orthodox or not in how your train and fight.
Western boxing developed independently of chinese martial arts style but lately, people are pulling from all over to make whatever it is they are training work.
We should be back at Pankration in a year or 5 at this rate.