I've had two falls but only one was bad enough to send me to the hospital.
I was riding a roan that I'd been riding for quite some time in an indoor barn in a private lesson. I'd known the horse for years. He was a great schooling horse, very gentle, loved me to death, a little slow and great for beginners which I loved. Enthusiastic with everything we tried and very patient for people willing to learn. Even when something possibly scary happened (like a sparrow flying into my face and slapping the horse when it fell,) he was super calm and well behaved.
That morning was overcast. When I was tacking him up I had noted that he was acting a little strangely but thought no more of it. I trusted him completely since he had never shown any kind of bad behavior previously. There were other horses that I would have expected bad behavior from- but not this guy.
I was learning to canter and he was a great horse to learn cantering on- he had a nice, slow canter that was really easy for me to handle. When we passed the entrance to the indoor ring however he must have seen something that spooked him. He started bucking out of nowhere. I lost my balance and as his head was coming up from bucking I was falling forward and he hit me in the face with his neck. It took me a minute to fall completely into unconsciousness. The next thing I knew I was freezing cold and the emergency personell were there asking me who the President of the United States was and I couldn't answer. I couldn't answer any of the questions they asked.
I passed out again- the next thing I knew I was in the ambulance. I woke up twice in the ambulance-long enough to tell them that I thought my pinky was broken (not because it hurt- but because it was twisted in the wrong direction,) and again when they were trying to cut my boots off. (They didn't have scissors strong enough-luckily I woke up when they tried, panicked at the thought of them cutting my brand-new, just broken in tall boots off, and told them the boots had zippers in the back.)
I woke up again in the hospital on a gurney. There were at least 6-10 people (all strangers and all of them were doctors,) standing over me. I had no clothing, not even a hospital gown, and only a sheet on for modesty's sake I guess; they cut all of my clothing off to check for injuries. I was freezing and in shock.
It turned out that the helmet did me quite a good turn. I had a mild to moderate concussion that left me with quite a bit of short-term memory loss. I had amnesia for the weeks surrounding the fall and couldn't remember anything past a few seconds. Mid-sentence I would forget what I was saying or that I was even having a conversation and wander off. My memory did improve but never came back completely.
When they went to examine my hand to see how it was broken it turned out that I had a 45-90 degree rotational spiraling compound fracture through the joint of my pinky. The doctors told me I was quite lucky- since I was already unconscious BEFORE falling off the horse the worst of my injuries were the broken pinky and concussion.
The doctors figure the blow to my face by the horse's neck knocked me out and as I was falling my hand got caught up in the reins. They said I got lucky- if I hadn't been unconscious, with the way I fell and the way my injuries indicated, I probably would have had a broken neck and internal injuries.
I had to have my hand surgically repaired. The concussion took months to go away. When I was cleared by the doctor I was eager to get back to riding but I was terrified. Everyone thought I would quit riding. Even though I trusted the horses I was riding I was scared of falling and winding up back in the hospital! I was pretty determined though and kept at it until I could ride and not be frightened. I had previously had so much fun riding- and it was so relaxing- that I was determined to get over my fear. (The little paint pony I rode after my recovery helped- SUCH a good boy!!)
My riding instructor, to my chagrin, would never let me ride that particular horse again. We never did find out what spooked the horse as the instructor said she was looking away the few seconds it took me to fall.
I can tell you now though- there is NO WAY I will ever skip wearing a helmet. I can only imagine with all the difficulties I had coming back from the concussion I got WITH the helmet how bad it would have been without one!!