My colleague was knocked off her bike last week. If she had not been wearing her helmet, she would most likely do dead, or have major head trauma. As it happens, she was, and is lucky to be alive.
She took a rear-vision mirror to the shoulder and was thrown through the air only two minutes from work. Not a scrape to the rest of her body, but took the majority of the force to her head. She has a depressed cheekbone, a fractured eye socket and lip and looks pretty beat up. They have shaved her head, cut her scalp, pushed her cheekbone back out, put three metal pins in her skull and stitched her back up. She has been in and out of hospital, is on serious pain killers, suffered from pretty bad nausea and memory loss.
For God’s sake people, wear your helmets. You might have great bike skills, but you just can’t trust the driver of the next car to pass you.