In surgery, there have been many advancements in the way that foot problems are corrected. The principles have generally stayed the same and there are some things about the seemingly 'old' or 'barbaric' way that are still relevant.
I have had patients come in after having had a surgery with another doctor, in disbelief that after surgery they found out that a 'hammer' and 'chisel' were used in their surgery. (The proper terms for the record are mallet and osteotome.) These are instruments that have been used in foot surgery for a long time. Some surgeons still use these for all surgeries they do and others still use them only in particular instances.
The newer form of these is using a powered bone saw.
So why wouldn't everyone convert to using a bone saw? For one, training. A surgeon goes through rigorous training and becomes well versed in their procedures as they were taught by more experienced surgeons. Some of these experienced surgeons have always been satisfied and comfortable using these 'older' instruments.
Another reason is that while a saw sounds much better and more refined, certain surgeries are better done the 'old school' way, as saws produce heat and if too hot can actually damage bone and other tissue in the foot making healing slower and pain worse after surgery.
The moral of the story is, there are many ways to get the same job done - even in foot surgery. Not every surgeon does the same procedure and not every patient condition responds well to the same techniques.