'They had to wean me off the morphine. It took me six months to dry out and it made me very wary of prescribed drugs. I had not realised how powerful they could be,' she said.
Ms Day, 35, had three major operations to her lower back. Today she wears a back brace and walks with sticks. She can no longer work as a designer in an advertising agency. She lives alone in London. 'I spent the next three years trying to cope. I did not eat much. Other drugs they gave me made me ill and sick. I am 5ft 9in and I went down to 7 stone,' she said.
Ms Day had smoked a little 'pot' as a student and she became interested when she started to read and hear that cannabis might help her. 'I have severe, chronic pain, always at night and if I have had a hard day. I was told that some people found cannabis helped.
'It is the only thing that stops my back 'screaming'. I find it totally relaxes all my muscles. It stops the spasms that lock my back up more and more. It is really effective. I can get a good night's sleep and it helps me, as well, to stop worrying. I have suffered real loss of my financial stability because of the accident.'
But she finds herself forced to ask her friends to supply cannabis resin for her. She pays the street price of about pounds 25 for a quarter of an ounce. She smokes cannabis about three or four times a week. 'It's a big problem. I feel very guilty about asking my friends to do this for me. I am forced to do something illegal but I will do anything that helps the pain.'
She says that she has been given a wide range of tablets over the years. 'But they had disturbing side effects, which cannabis does not. The (pharmaceutical) drugs used to make me bounce off the walls. I could not get my head together, they affected my digestion.
'With cannabis I never really hit it. I don't get 'high' - and the pain never really goes away. But I am more relaxed and I am better able to cope with it.
Hannah Day is a pseudonym.