Why were chainsaws invented?

Doctors used them to help with childbirth
Before you think too far, chainsaws were not as big then as they are now. The original chainsaw, invented by Scottish doctors John Aitken and James Jeffray, was a “flexible saw” used for removing ossified (bone-like) tissue during childbirth.

 

So that explains the strange scar on my head! Had to cut me free somehow!

 

The same one that goes right down your back to about a foot below your belt line.

 

No that's a different one. The doctor held me up by the ankles to slap my back and dropped me on the delivery room floor. He then picked me up and passed me around so all the nurses had a turn too!