On 3/5 we were out of state on vacation, after we completed shopping for the day I was placing my shopping bags in the trunk of the vehicle. My friend, unaware that I had not stepped out of the way activated the self closing trunk door. The door failed to detect that there was an obstruction (me) and closed striking me on the top left side of my head causing me to have a concussion. I was seen at my doctor's office days later due to the headaches and other symptoms from the injury and was diagnosed as resulting from a traumatic head injury. The door deactivated after striking me and had to be reset manually. However, my concern is that a sensor should have detected that there was an obstruction and stopped or not closed at all. Other makes and models will have an alarm and will not close when there is an obstruction. I called Land Rover today at 4:51 p.m. and the representative could not find anything in the owner's manual that stated there is a sensor of any type. The doctor placed me off of work but as I am my only source of income, I am unable to stop working in order to recover. My vehicle is available for inspection if needed.