Hi
@Ed Norton
In my case I think it might be a combination of quite complex factors, such as spending the first five years in care, then being adopted, and having repeated surgical procedures regularly throughout my childhood (until I was 16). I can't say that one single event caused PTSD, but I guess it's possible.
I don't remember much of the earliest stuff, just flashes and brief moments generally. Some of the most upsetting events I do remember occurred when I was older and when I was a teenager. These events are a combination of painful medical treatments (and therefore frightening) and embarrassing and humiliating acts (primarily because the surgery was on my genitals) that I felt most acutely when I was a teenager (I probably didn't worry about some of these acts when I was younger).
Another factor that I am sure is very relevant for me was knowing in advance from previous surgeries and hospitalisations what was going to happen, what was going to hurt, or be unpleasant. For example I knew from previous surgeries that passing water after the operation was excruciatingly painful. Knowing that when I peed I would pass blood and it would be agony, but also being forced to drink lots after surgery by nurses to make me pee, and holding it in because I was so scared of the pain until I simply couldn't hold it any longer - well psychologically I can see why that scenario would be potentially damaging, even more so as it was repeated so often throughout my childhood. The same applies to being held down and having stitches removed from my penis (not under anaesthetic) following each surgery, being held down and force feed medicines that were disgusting and made me vomit, prior to each surgery. And so on.....Knowing in advance that these things were going to happen again and again I think was a major source of trauma, for me, as well as the event itself.
I've never felt comfortable claiming I was traumatised by medical treatments. Compared to acts of intentional abuse (sexual and otherwise) I always felt it was wrong to even suggest my experiences were traumatising (and I still struggle with this). Add to this the fact that the medical treatment was intentional, to make me better - and I was left with a feeling that it was wrong and weak of me to 'claim' it was traumatising. My parents repeatedly told me I had to be brave - I guess as a child I interpreted that to mean I mustn't show and express my fears. Hence it has taken until I am in my fifties to start to admit and say I think this may have been traumatising for me.
Sorry for the long and detailed answer, it just so happens that medical treatments were the major part of my childhood (along with a few isolated acts, in the guise of medical treatment, that I believe were sexually abusive). As I said, it's complex.
Anyway I hope I haven't bored you to tears....and this is of some help and interest.
Mit