Just reading the previous few posts, including the first ones of this thread, it struck me that it was probably likely that the patient did not need the C-spine or the oxygen to be administered. Even though the patient was alert and oriented, but did not know why she fell, tells me that she may have had a seizure given the fact that she's in a drug rehab facility. A thorough examination should rule out spinal precautions as something that is necessary, and the fact that she is breathing, has no shortness of breath issues, is warm pink and dry, and so on tells me that she probably does not need supplemental oxygen. If I were to hazard a guess, she probably fell on her side, with her arms at her side, or she fell on something that resulted in fracture of her clavicle. I think that is the only injury she sustained based on these signs and symptoms she had: a deformity and point tender on her clavicle.
I can understand placing the patient C-spine precautions by protocol, because you have to, for unwitnessed mechanical fall, even if it's a ground-level fall. Given her overall presentation, I do not see any indication for oxygen at this time. Most likely, even if I had a pulse oximetry are handy, I would not have used it, unless I had to by protocol.
My treatment plans are derived from my own evaluation of the patient. I say evaluation instead of assessment, because I don't just take into consideration physical findings, I try to look at as much of the clinical picture as I can. I then come up with a treatment plan that makes sense given the presentation. I then implement what I can, based upon my limitations as a provider. If I'm working as an EMT, I only do EMT stuff, if I'm working as a paramedic, I add the paramedic level stuff as well.
That particular patient, I probably would consider not putting the patient in C-spine, I would not put the patient oxygen, I probably would however provide an ice pack of some sort to control pain. That would be if I was working as an EMT. As far as transport decision goes, no lights, no siren, no drama. If I was a paramedic working that particular call, I would probably do the same things as above, and consider opiate pain control measures if the ice was not working, depending upon specific protocol for pain control and trauma. Otherwise, I would just "BLS it in" and call it good.
The only thing else I would add would be finding out why the patient was admitted to the drug rehab facility. We can see polypharmacy issues in skilled nursing facilities, but it is not out of the realm of possibilities that polypharmacy could be a big issue with these types of facilities too.
So, after all of this rambling, taking all of the above into consideration, I would simply transport patient in a position of comfort, cold pack on the clavicle, nice quiet ride to the ED for evaluation. The other guys have certainly covered the issues of too much oxygenation. My take on oxygen is simply this: it is a drug, it is relatively benign, like all drugs it can be harmful if used improperly. That is why you only give it when it is indicated in the amounts that it is indicated for.