Thread by @vagina_museum

In the entire Texas Chainsaw Massacre franchise there are fewer than 20 deaths by chainsaw.

But did you know that chainsaws saved many lives in the 18th and 19th centuries when they were invented as an obstetric surgical tool?

Chainsaws were invented in the late 18th century, roughly simultaneously by two different Scottish physicians: John Aiken, who invented one for an obstetric procedure, and James Jeffray who invented the same device for use in removing diseased bone. We'll be talking about Aiken.

In 1785 when Aiken published his textbook Principles of Midwifery, or Puerperal Medicine, obstructed labour - where the baby can't pass through the bones of the pelvis - was highly dangerous and frequently lethal. There were three options available for treatment. None were great.

First of all there was C-section (which Aiken called "hysterotomy"). This carried an 85% mortality rate and came with numerous ways of dying, such as infection from unclean tools or hands; blood loss; or shock from the pain of undergoing abdominal surgery without anaesthetic.

Then there was craniotomy (which Aiken called "embryotomy"). This was always lethal to the baby and only performed if it was already dead, because it involved crushing the bones of the head to extract it.

And finally, there was symphysiotomy (which Aiken called "pelviotomy"). This was the only procedure where there was really a chance of survival for both, although it was still very risky. This operation was invented in the late 16th century.

Symphysiotomy involves dividing the cartilage of the pubic symphysis, the joint between the pubic bones, in order to create more space in the pelvis for the baby to pass through. It was a painful procedure coming with plenty of risks, but far less risky than a C-section in 1785.

Typically, symphysiotomies were performed using scalpels, but this increased risks of complications such as puncturing the bladder, or being unable to get through ossified cartilage. And here's where Aiken's chainsaw comes in.

Aiken recommended using his "flexible saw" to address some of the risks of the symphysiotomy. He recommended using the saw to divide the cartilage. This is what his tool looked like:

Symphysiotomy fell out of favour in the 20th century as improvements to surgery such as hygiene, anaesthesia, blood transfusion and better techniques made C-section a survivable and overall better procedure with better outcomes.

Since the 20th century, symphysiotomies are seldom performed, although are recommended in rural and resource-poor areas where an operating theatre isn't available for C-section... and a scandal in Ireland in the second half of the 20th century.

We can't talk about symphysiotomy without addressing that between 1944 and 1987, over 1500 symphysiotomies were performed in Ireland without consent and where C-section was available as an option. Many women were disabled or left in pain by the procedure.

However, in the 18th and 19th centuries, the symphysiotomy was a life-saver, in absence of the better alternatives we have today. So there you have it. Back in the day, chainsaws saved lives.