There are several important injury biomechanics which are not available online. Here's a summary of how to get the full papers from these conferences.
SAE Technical Papers: These are full text in the SAE Mobilus database. Please note that if you find these papers in Google Scholar, even from on campus, you won't see the "UBC eLinks" that take you to the full paper. You must search SAE Mobilus directly.
AAAM (Association for the Advancement of Automotive Medicine):
Stapp Car Crash Journal / Stapp Car Crash Conference:
IRCOBI (International Research Council on the Biomechanics of Impact):
NHTSA ESV (Enhanced Safety Vehicles) are available online from 1971-present.
If UBC doesn't have access to the proceedings or technical paper you need, you can request it through Interlibrary Loan.